KR20050092427A - Tube with high dimensional accuracy and method and device for manufacturing the tube - Google Patents

Abstract

A tube with a high dimensional accuracy manufacturable at low cost and having sufficient fatigue strength throughout the wide range of size requirement of the tube and a method of manufacturing the tube. With a plug (1) inserted into a metal tube (5), the metal tube (5) is pushed and passed through the hole of a die (2) for pushing-out. Thus, the pushed-out tube with the high dimensional accuracy in which one or more of an outer diameter deviation, inner diameter deviation, and circumferential wall thickness deviation are 3.0% or less can be provided.

Description

Tube with high dimensional accuracy and method and device for manufacturing the tube

TECHNICAL FIELD This invention relates to a high precision precision pipe, its manufacturing method, and a manufacturing apparatus. The present invention relates to a high dimension precision tube, a method of manufacturing a high dimension precision tube, a manufacturing apparatus, and a manufacturing facility that can be applied to a high dimensional precision such as an automobile drive system component.

Metal tubes, such as steel tubes, are generally divided into welded and seamless tubes. A welded tube is produced by, for example, rounding the width of a large plate, such as an electric resistance pipe, by welding both ends of the rounded width. On the other hand, a seamless pipe is manufactured by drilling a solid billet at high temperature, and then rolling it with a Mandrel Mill or the like. In the case of a welded pipe, after the welding, the raised part of the welded part is ground to improve the dimensional accuracy of the pipe, but the thickness deviation exceeds 3.0%. In addition, in the case of a seamless pipe, it is easy to eccentric in a drilling process, and a big thickness deviation tends to occur by the eccentricity. Efforts have been made to reduce this thickness deviation in a later step, but this cannot be sufficiently reduced, and it remains at least 8.0% in the product stage.

In recent years, as a countermeasure for environmental problems, lightweight automobiles are strongly desired. Drive system components such as drive shafts are being replaced by hollow metal tubes in solid metal bars. Metal tubes such as automotive drive system components are required to have high dimensional accuracy of 3.0% or less, more precisely 1.0% or less, as variations in thickness, inner diameter, and outer diameter.

The drivetrain components must withstand the fatigue caused by long-distance travel of the vehicle. If the thickness, inner diameter, and outer diameter of the metal tube are poor, inevitably, fatigue breakdown tends to progress from the unevenness existing on the outer surface of the pipe, and the fatigue strength is significantly reduced. In order to maintain sufficient fatigue strength, it is necessary to improve the precision of the thickness, inner diameter, and outer diameter of the metal tube.

Hereinafter, the high dimension precision referred to in the present invention is a tube in which any one or two or more of the outer diameter deviation, the inner diameter deviation, and the circumferential thickness deviation are 3% or less, and each deviation is derived by the following equation.

Deviation = fluctuation range / (target value or average value) × 100%

Amplitude = maximum-minimum

Generally, the following two methods are known as a means of improving the precision of the thickness, inner diameter, and outer diameter of a metal tube. Hereinafter, a welded steel pipe and a seamless steel pipe (hereinafter referred to as a steel pipe or a pipe) will be described.

One is a method (so-called cold drawing method) which draws a steel pipe by cold using a die and a plug (refer patent document 5). The other one is the method (the rotary forging press-fitting method) which presses a steel pipe into a die hole and processes it using the rotary forging machine which assembled the dice divided | segmented in the circumferential direction (refer patent document 1, 2, 3). .

Patent Document 1: Japanese Patent Application Laid-Open No. 9-262637

Patent Document 2: Japanese Patent Application Laid-Open No. 9-262619

Patent Document 3: Japanese Patent Application Laid-Open No. 10-15612

Patent Document 4: Japanese Patent No. 2858446

Patent Document 5: Japanese Patent No. 2812151

However, in the cold drawing method, when the facility capacity is insufficient, or when the thickness and diameter of the pipe are large, the pullout stress cannot be sufficiently obtained, and the shaft diameter ratio must be lowered. The gap between the die and the tube and the draw plug and the tube is insufficient in the gap between the inner surface of the die and the hole. The cold drawing method is because the stress of a tube is a tensile force. In this case, smoothing of the inner surface and the outer surface of the tube is insufficient, and unevenness easily remains. As a countermeasure, cold drawing is used to increase the shaft diameter of the tube and to improve the contact between the inner and outer surfaces of the tube, the plug and the die in the machining bite. However, when the tube is cold drawn using a die, as the axis diameter of the tube increases, the roughness due to the unevenness of the inner surface of the tube increases. As a result, in cold drawing, it is difficult to obtain a tube of high dimension precision. Therefore, the fatigue strength of the pipe | tube is not enough, and the pipe | tube with favorable dimensional precision is strongly requested | required. In cold drawing, it is necessary to close the tip of the tube because the tip of the tube is fitted in order to apply tension. As a result, it was forced to draw one by one, resulting in a problem of significantly lower processing efficiency.

In addition, even when there is a facility capability and the axial diameter can be increased, the processing twist due to the axial diameter becomes large and the tube is easily vulcanized. After drawing, the tube is further subjected to processing such as bending and swaging. By the work hardening in the said drawing, there existed a problem which a crack generate | occur | produced easily in a subsequent bending process etc. In order to prevent it, it is necessary to apply heat treatment at high temperature after drawing for a sufficient time, and manufacturing cost is remarkably high, so there is a desire for a method of efficiently manufacturing high-precision precision tubes that are easy to process at low cost. Has been.

Moreover, the pressurizing apparatus of the metal tube described in patent document 4 is an auxiliary apparatus for tensioning a metal tube with another apparatus, and preventing the fracture | rupture of the tube by the tension, and reducing the tension force required in order to form a groove | channel in an inner surface. It does not smooth the inside and outside surfaces.

In the rotary forging press-fitting method described in Patent Literatures 1 to 3, the die of the rotary forging machine is divided and the die is rocked. As a result, a step is likely to occur at the divided portion, so that smoothing of the outer surface is insufficient or other dies in the circumferential direction Uneven deformation may occur due to the stiffness of. As a result, since the precision of thickness was also insufficient, the target finishing dimension precision was not fully obtained, and the fatigue strength of the steel pipe was not enough, but improvement was required.

In the rotary forging press-fitting method, the thickness after press-fitting the steel pipe is thicker than the thickness before press-fitting. It uses a rotary forging machine that is difficult to apply a load because it has a complicated structure, but there is a limitation. In order to increase the thickness, it is easy to deform the pipe by increasing the gap as close to the exit in the processing bite. However, when the gap is easily deformed, irregularities are generated on the inner surface of the pipe. Moreover, increasing the thickness increases the gap, and the tube is not sufficiently in contact with the die surface or the plug surface. As a result, smoothing of the tube surface did not progress, and it had a drawback that it was difficult to obtain a high precision precision pipe.

In the manufacture of high precision precision tubes, defects such as burn marks on the surface of the pipe during processing will occur if the friction between the outer surface of the plug, the inner surface of the pipe and the inner surface of the die and the outer surface of the die is reduced as much as possible. Not only does the surface quality deteriorate, the tube does not become a product, but also the load at the time of processing increases remarkably, and the processing itself becomes impossible. As a result, the production efficiency is significantly reduced.

As a result, if the desired thickness is to be obtained after the press fitting, the thickness before the press fitting can be reduced. Therefore, in order to equip pipes of various product sizes and to improve the performance of the pipes, such as fatigue strength, a large number of small pipe sizes must be prepared. However, it is difficult to obtain good dimensions over the entire required size of the pipe because many pipe sizes cannot be prepared because of limitations in the element pipe manufacturing equipment. In addition, in automobile parts, the degree of processing of the pipe can be changed and used. For example, in some parts, it is considered to reduce the workability and omit the heat treatment after work. In another part, the workability can be significantly increased to increase the strength.

However, in the conventional cold drawing or rotary forging press-fitting method, only the shaft diameter is processed, and the outside diameter after processing is uniquely determined by the die diameter, and the thickness is uniquely determined by the die and the plug. Only a unique processing degree can be obtained from the element pipe, and it was almost impossible to produce a pipe of the same size with different degree of workability from the same element pipe. Therefore, in order to manufacture a pipe with a different processability with the same size, it is inevitable to prepare several pipe | tubes of various sizes, and to change a shaft diameter rate, and the labor of producing a pipe | tube was enormously hard.

As described above, in the prior art, it is difficult to obtain a tube of high dimension precision, and there is a problem in that a large number of small tubes having different sizes must be prepared when manufacturing tubes having the same size and different processing degrees.

MEANS TO SOLVE THE PROBLEM In order to solve the problem mentioned above, the present inventors examined the processing method which can produce steel tubes with dimensional precision higher than drawing, and came to the conclusion that compression was a potent candidate. In the case of pressurization, as shown in FIG. 10, the plug 4 is inserted into the pipe 4, and the pipe 4 is pushed in the pipe indenter 3 while the plug 1 is floating. By press-fitting into the furnace die 2, the total compressive stress acts in the machining bite. As a result, the pipe can fully contact the plug and the die regardless of the inlet side and the outlet side of the processed bite. Moreover, even at a small shaft diameter, the machining bite is in a compressive stress state, so that the tube and the plug, the tube, and the die are more easily in contact with each other than the drawing, and the tube is easy to be smoothed, so that a tube of high precision can be obtained. have.

However, during the press working, the plug is pushed into the pipe so that the load is increased, and as a result, a small pipe to be pressed is buckled and processing becomes impossible. The causes include insufficient coating amount of lubricant, change in surface properties of element pipes, deformation of plugs and dies due to frictional heat and processing heat during pressing, and so on. In order to continue, it is first necessary to determine on the spot during processing whether or not it is workable.

Conventionally, the operator sensibly judges the vibration sound of a tube presser, a fluctuation of an oil pressure meter, or the like, or forcibly cuts the die so that the die is cracked to stop the machining. The conditions were reviewed and processed again. In other words, the condition was changed even in a state in which machining was much better than the pressing limit, or the die was cracked in an extremely strict machining state, and thus the condition was changed. As a result, unnecessary machining time is required, or the die exchange is considerably time consuming, resulting in low productivity.

In the conventional drawing, in order to improve the dimensional accuracy of the tube, the tube must be bonded to the power generation, and then metal soap should be applied to form a sufficient lubrication film. Therefore, it is necessary to take sufficient time to form the lubrication film. Moreover, the pretreatment of the pipes, such as pickling, was also required, and the plurality of containers for the pretreatment, such as pickling, and the plural containers for the lubrication treatment were required for the heat of equipment for drawing. In addition, in order to carry out drawing work, it was necessary to apply soldering to a pipe end part using a rotary forging machine or the like. However, if these equipment rows are brought online and arranged at the inlet side of the drawing processing machine, the productivity decreases and this is a big problem. Therefore, the pipes are lubricated in a separate process, and the pipes are connected to the drawing online equipment rows. Input was processed.

That is, it is difficult to improve manufacturing efficiency in the conventional manufacturing equipment row of a high precision precision pipe because it presupposes drawing process which requires a long pretreatment process.

As described above, in the conventional cold drawing or rotary forging press-fitting method, it is difficult to obtain a tube of high dimension accuracy and the problem that the surface quality of the tube may be deteriorated remains unsolved.

In view of the above-mentioned problems of the prior art, the present invention provides a high-precision precision tube that can be manufactured at low cost over a wide range of required sizes of a tube, and has a sufficient fatigue strength, a manufacturing method thereof, and a production for producing efficiently. It is an object to provide facility heat.

Disclosure of the Invention

This invention which achieved the said objective is as follows.

(1) Any one or two or more of an outer diameter deviation, an inner diameter deviation, and a circumferential thickness deviation produced by pressing a metal tube by press-fitting it into a hole of a die while a plug is inserted in the tube is 3.0%. High precision precision tube as it is pressurized, characterized by the following.

(2) An outer diameter deviation and an inner diameter manufactured by pressing the metal tube by pressing the die into the hole of the die while the plug is inserted into the tube and making the thickness of the metal tube on the outlet side of the die less than that of the inlet side. Any one or two or more of a deviation and circumferential thickness deviation are 3.0% or less, The high precision precision tube as described in (1) characterized by the above-mentioned.

(3) The pressing is performed while the metal tube is made with the entire circumference of the circumference of the plug and the entire circumference of the die in the same cross section of the tube, as described in (1) or (2). High dimension precision tube.

(4) The high-precision precision tube according to any one of (1) to (3), wherein the die is an integral and / or fixed die.

(5) A method for producing a high precision precision pipe, wherein the metal pipe is pressed through a hole in a die while a plug is inserted in the pipe.

(6) The manufacturing method of the high precision precision pipe according to (5), wherein the thickness of the pipe on the outlet side of the die is equal to or less than the thickness of the pipe on the inlet side of the die.

(7) The method for producing a high precision precision pipe as described in (5) or (6), wherein the pressing is performed while the metal pipe is in the same cross section of the pipe with the entire circumference of the circumference of the plug and the entire circumference of the die. .

(8) The method for producing a high precision precision tube according to any one of (5) to (7), wherein the dice are integral and / or fixed dies.

(9) The method for producing a high precision precision tube according to any one of (5) to (8), wherein the plug is a floating plug.

(10) The method according to (5), wherein any one or two or more of the outer diameter deviation, the inner diameter deviation, and the circumferential thickness deviation of the tube are improved by pressing to form a high-precision precision tube, or the plug is inserted into the tube and floated. A high efficiency manufacturing method of a high precision precision pipe, wherein the pipe is continuously transferred into the die by a pipe transfer means on the die inlet side.

(11) The high efficiency manufacturing method of the high precision precision pipe according to (10), wherein the pipe conveying means is a caterpillar for holding a pipe before processing.

(12) The high efficiency manufacturing method of the high precision precision pipe according to (10), wherein the pipe conveying means is an endless belt that presses the tube before processing.

(13) The high efficiency manufacturing method of the high precision precision pipe according to (10), wherein the pipe conveying means is a mechanism for grasping a tube before processing and transferring it intermittently alternately.

(14) The high efficiency manufacturing method of the high precision precision pipe according to (10), wherein the pipe conveying means is a press that sequentially presses the tube before processing.

(15) The high efficiency manufacturing method of the high precision precision pipe according to (10), wherein the pipe conveying means is a hole roll for sandwiching a pipe before processing.

(16) The high efficiency manufacturing method of the high precision precision pipe described in (15), wherein the hole roll is a hole roll of two or more rolls.

(17) The high efficiency manufacturing method of the high precision precision pipe as described in (15) or (16) characterized by providing two or more said stand rolls.

(18) The high precision precision pipe according to (5), wherein after forming a lubricating film on the inner and / or outer surface of the tube, the plug is inserted into the tube and the tube is pressed by a die. Manufacturing method.

(19) A method for producing a high-precision precision tube with good surface quality as described in (18), wherein the pipe forming the lubricating film is a steel pipe with an oxide scale.

(20) A method for producing a high-precision precision tube with good surface quality according to (18) or (19), wherein the lubricating film is formed by using a liquid lubricant.

(21) A method for producing a high-precision precision tube with good surface quality according to (18) or (19), wherein the lubricating film is formed by using a grease-based lubricant.

(22) A method for producing a high-precision precision tube with good surface quality according to (18) or (19), wherein the lubricating film is formed by using a dry resin.

(23) The above-mentioned dry resin, or a liquid obtained by diluting the dry resin with a solvent, or an emulsion of the dry resin is applied to a tube, followed by warm air, or by air drying to form the lubricating film. A method for producing a high dimension precision tube with good surface quality as described in (22), wherein the surface quality is excellent.

(24) The method for manufacturing a high precision precision pipe according to (5), wherein a high precision pipe is manufactured from a same size pipe having a different degree of workability. A method for producing a high precision precision pipe, comprising inserting a shaft diameter-capable plug into a pipe and pressing the pipe with a die.

(25) The manufacturing method of the high precision precision pipe as described in (24) characterized by floating the said plug in a pipe, and supplying a pipe to a die continuously.

(26) The method for producing a high precision precision pipe according to (24) or (25), wherein the plug is a plug in which the tapered angle of the expansion portion is less than the tapered angle of the shaft diameter portion.

(27) The method for producing a high precision precision pipe according to any one of (24) to (26), wherein the target outer diameter of the pipe on the outlet side of the die is less than the outer diameter of the pipe on the inlet side.

(28) The method of (5), wherein the surface of the shaft diameter portion as the plug forms the machining central axis in the manufacture of the high-precision precision tube by press-processing by press-fitting the tube into which the plug is inserted into the hole of the die. A plug having an angle of 5 to 40 degrees and a length of the shaft diameter portion of 5 to 100 mm is used, and a die having an angle of 5 to 40 degrees in which the inner surface of the hole on the inlet side forms an angle with the machining center axis is used as the die. Stable manufacturing method of high precision precision pipe made with

(29) The method for stably manufacturing a high precision precision tube according to (28), wherein the bearing portion of the plug has a length of 5 to 200 mm.

(30) The stable manufacturing method of the high precision precision pipe according to (28) or (29), wherein the thickness of the pipe on the outlet side of the die is set to be equal to or less than the thickness of the pipe on the inlet side.

(31) The method for stably manufacturing a high precision precision tube according to any one of (28) to (30), wherein an integrated fixed die is used as the die.

(32) The method for stably manufacturing a high-precision precision tube according to any one of (28) to (31), wherein the plug is floated in the tube.

(33) The method for producing a high precision precision pipe according to (5), wherein the plug is inserted into a pipe and floated, and the pipe is press-fitted into a die and passed through. Measure the load and compare the measured load with the calculated load calculated by any one of the following [Equation 1] to [Equation 3] from the material characteristics of the element pipe, which is a pipe before processing, and based on the result, it is determined whether or not to continue the pressing process. A stable manufacturing method of a high dimension precision pipe characterized by the above-mentioned.

[Equation 1] σ _k × elementary pipe cross-sectional area

Where σ _k = YS x (1-a x λ), λ = (L / √n) / k, a = 0.00185 to 0.015, L: tube length, k: cross-section secondary radius, k ² = (d ₁ ² + d ₂ ² ) / 16, n: tube end state (n = 0.25 to 4), d ₁ : outer diameter of tube, d ₂ : inner diameter of tube, YS: yield strength of tube

Yield strength YS × tube cross-sectional area of tube

Equation 3 Tensile strength TS of element pipe

(34) If the measured load is less than or equal to the calculated load, processing is judged to be continued and processing continues as it is, while if the measured load is greater than the calculated load, it is determined that it cannot be continued, and the processing is stopped, and dies and And / or replacing the plug with one of a different shape corresponding to the same product size, and then processing is resumed.

(35) The method for stably manufacturing a high precision precision tube according to (34), wherein the dice and / or plugs used after the replacement are smaller in angle than the ones before the replacement.

(36) The lubricant is applied to the element pipe prior to the pressing operation, and the kind of the lubricant is changed only when the measured load is greater than the calculated load. Stable manufacturing method of high dimension precision pipe described.

(37) A metal tube having a plug which can contact the entire inner circumference of the metal tube, a die having a hole which can contact the entire outer circumference of the tube, and a tube press for crimping the tube, wherein the metal tube is inserted into the tube. The apparatus for manufacturing high-precision precision pipes, characterized in that the press-fitting of the dies by press-fitting into the holes of the die is performed.

(38) The apparatus for manufacturing a high precision precision tube according to (37), wherein the dice are integral and / or fixed dies.

(39) The apparatus for producing a high precision precision tube according to (37) or (38), wherein the plug is a floating plug.

(40) The apparatus for producing a high precision precision tube according to any one of (37) to (39), wherein the tube press continuously presses the tube.

(41) The apparatus for producing a high precision precision tube according to any one of (37) to (39), wherein the tube press presses the tube intermittently.

(42) The method for producing a high precision precision pipe according to (37), wherein the plug is inserted into a pipe and floated, and the pipe is pressed continuously and intermittently into a die and passed. High efficiency of high precision precision pipes, wherein dies are arranged on the same circumference, and any one of these dice is moved in the circumferential direction arranged according to the product dimension and arranged in a pass line to be used for pressing. Manufacturing method.

(43) The method for manufacturing a high precision precision pipe according to (37), wherein the plug is inserted into a pipe and floated, and the pipe is pressed continuously and intermittently into a die and passed. A die is arranged on the same straight line, and any one of these dice is moved in a straight line arranged in accordance with the product dimensions, placed in a pass line, and used for compression.

(44) In changing the product dimensions from the preceding tube to the next tube, after the end of the compression of the preceding tube, the next tube is stopped on the die inlet side, before or after movement of the die according to the product dimension of the next tube, or The high efficiency manufacturing method of the high precision precision pipe as described in (42) or (43) characterized by inserting the plug according to the same product dimension into the following pipe | tube in the movement.

(45) The method according to (37), wherein the die which passes the tube, the indenter which presses the tube into the die in the pass line, and a plurality of dies are supported in a form arranged on the same circumference and conveyed in the circumferential direction thereof. A high efficiency manufacturing apparatus for high precision precision pipes having a die swivel for placing two dice in a pass line.

(46) The method according to (37), wherein the die through which the tube passes, the indenter for pressing the tube into the die in the pass line, and the plurality of dies are supported in a form arranged on the same straight line and conveyed in the linear direction. A high efficiency manufacturing apparatus for high precision precision pipes having a straight line for placing two dice in a pass line.

(47) The manufacturing method of the high precision precision pipe | tube which inserts and floats a plug in a pipe | tube, and presses the pipe | tube into a die and passes it, The installation method provided in the vicinity of the said die exit side is provided. A method for producing a high precision precision pipe, wherein bending of the pipe is prevented by passing the pipe on the die exit side through a hole shape in which an in-plane position orthogonal to the (tube) direction is adjusted in advance.

(48) The manufacturing method of the high precision precision pipe as described in (47) characterized by passing the tube of the said die inlet side and / or the said hole type | mold outlet side through a guide cylinder.

(49) A method for producing a high precision precision tube according to (47) or (48), wherein the tube is continuously press-fitted into a die.

(50) The manufacturing apparatus of the high precision precision pipe which has the die which passes a pipe | tube, and the indenter which presses a pipe | tube in this dice | dies, WHEREIN: The hole type which passes a pipe just near the said die exit side. And a support substrate for movably supporting the hole shape in a plane orthogonal to the clearance direction, and a pipe bending fine adjusting means having a hole moving mechanism supported by the support substrate to move the hole shape. Manufacturing equipment of high dimension precision pipe made.

(51) A method in which the hole-type moving mechanism presses one or two or more portions of the hole-shaped outer peripheral portion in a direction orthogonal to the clearance direction through a tapered surface of a wedge-shape mold moving in the clearance direction. The manufacturing apparatus of the high precision precision tube as described in (50) characterized by the above thing.

(52) The manufacturing apparatus of the high precision precision pipe as described in (51) characterized by pushing the movement of the said wedge-shaped die with a screw.

(53) The high-precision precision tube described in (50), wherein the hole-type moving mechanism is of a type that pulls out or draws out one or two or more portions of the hole-shaped outer peripheral portion in a direction orthogonal to the direction of direct passage. Manufacturing equipment.

(54) An apparatus for manufacturing high precision precision tubes as described in (53), wherein the press-in or pull-out of the press-in or pull-out method is pushed by a fluid pressure cylinder.

(55) The apparatus for manufacturing a high precision precision pipe according to any one of (50) to (54), wherein the hole diameter of the hole is equal to or larger than the exit hole diameter of the die.

(56) The apparatus for producing a high precision precision pipe according to any one of (50) to (55), wherein the hole of the hole type is a straight hole or a tapered hole.

(57) Furthermore, the high-precision precision tube according to any one of (50) to (56), which has a guide tube for passing the tube at the die inlet side and / or the tube bend fine adjustment means outlet side. Manufacturing equipment.

(58) The apparatus for producing a high precision precision pipe according to any one of (50) to (57), wherein the indenter is a continuous indenter capable of continuously indenting the tube.

(59) A pipe section grinding device for manufacturing a high-precision precision pipe having a press-fitting plant value as described in (37), wherein the pipe section grinding device grinds the cross section of the pipe at a right angle in the tube axial direction; A manufacturing apparatus line for high-precision precision pipes, comprising a coating vessel, a drying apparatus for drying a tube coated with a lubricant, and the press-fitting plant in this order.

(60) Furthermore, a row of equipment for manufacturing high precision precision tubes according to (59), wherein a cutting device for cutting the tube into short lengths is disposed at an inlet side of the pipe section grinding device.

(61) Instead of the lubricant immersion coating container and the drying apparatus, a lubricant spray coating apparatus for spraying and applying lubricant to a tube at a die inlet side of the press processing apparatus, or a lubricant spraying and applying a lubricant to a tube and then drying the lubricant A line of manufacturing equipment for high precision precision tubes according to (59) or (60), characterized in that a spray coating drying apparatus is disposed.

(62) One of a die exchanger for replacing the die, a plug exchanger for exchanging the plug, and a bending prevention device for preventing bending of the pipe on the die outlet side in addition to the press-processing device. Or 2 or more arrange | positioned, The manufacturing equipment row of the high precision precision tube in any one of (59)-(61) characterized by the above-mentioned.

BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing which shows embodiment of the compression used by this invention.

2 is an explanatory diagram showing an embodiment of a conventional drawing.

It is explanatory drawing which shows embodiment of the press injection by the rotary forging machine which mounts and swings the conventional dicing dice | dies, and is sectional drawing containing a center of gravity axis | shaft.

FIG. 3B is an explanatory diagram showing an embodiment of the press-fit by the rotary forging machine which mounts and swings a conventional dicing die, and is a view shown by an A-A arrow. FIG.

4 is a characteristic diagram showing the relationship between the stress and the endurance recovery in the fatigue test.

5 is a longitudinal cross-sectional view showing an example of the present invention using a caterpillar as the pipe conveying means.

Fig. 6 is a longitudinal sectional view showing an example of the present invention using an endless belt as the pipe conveying means.

Fig. 7 is a longitudinal sectional view showing an example of the present invention using an intermittent feeder as the pipe feed means.

Fig. 8 is a longitudinal sectional view showing an example of the present invention using a hole roll as the pipe conveying means.

9 is an explanatory view of a tapered angle of a part of the plug.

10 is a cross-sectional view showing the outline of the pressing process.

It is a schematic diagram which shows embodiment of the method of this invention using the 1st example of this invention apparatus.

It is a schematic diagram which shows embodiment of the method of this invention using the 2nd example of this invention apparatus.

It is explanatory drawing about the comparative example (exchange dice by hand).

14 is a perspective view showing one embodiment of the present invention.

Fig. 15 is a plan view showing an example of pipe bending fine adjustment means according to the present invention.

It is sectional drawing which shows an example of the hole-type moving mechanism which concerns on this invention.

17 is a perspective view showing one embodiment of the present invention.

18 is a plan view showing an example of the pipe bending fine adjustment means according to the present invention.

19 is a perspective view illustrating one of the comparative examples.

20 is a perspective view illustrating one of the comparative examples.

21 is a perspective view illustrating one of the comparative examples.

It is a schematic diagram which shows the arrangement | positioning of the equipment row which used the Example of this invention.

It is a schematic diagram which shows the pretreatment process required for arrangement | positioning and drawing process of the plant heat | fever used as a comparative example.

To practice the invention  Best form for

In the conventional cold drawing method, when drawing a metal tube using a die and a plug, it was difficult to improve the dimensional accuracy of the tube. This is because the pull force acts as a tension, so that the contact between the die and the tube outer surface and the plug and the tube inner surface in the machining bite becomes insufficient. As shown in FIG. 2, the plug 1 is inserted into the tube 5, and the tube 5 is pulled out of the hole of the die 2 to draw force 9 applied to the exit side of the die 2. As a result, tensile stress is generated inside the processed bite, and irregularities are generated and increased on the inner and outer surfaces of the pipe from the inlet of the processed bite toward the outlet side. In addition, at the inlet side in the processing bite, the outer surface of the tube does not contact or slightly touches the plug 1 so as to deform along the inner surface of the plug. On the exit side in the machining bite, the tube inner surface is not in contact or slightly contacts in order for the outer surface of the tube to contact and deform the die 2. Therefore, the part which can be deformed freely exists with the inner and outer surfaces of a pipe | tube, and the unevenness | corrugation cannot be smoothed enough, and the dimensional precision of the pipe obtained after drawing was low.

In contrast, in the pressing method of the present invention, as shown in FIG. 1, the plug 1 is inserted into the tube 5 to press the tube 5 into the hole of the die 2. Pass it through. By the pressing force 8 applied to the inlet side of the die 2, the compressive stress acts on the entire surface inside the machining bite. As a result, the tube 5 can fully contact the plug 1 and the die 2 over the entire circumferential region in the same cross section on either the inlet side or the outlet side of the machining bite. Moreover, even at a slight shaft diameter, the inside of the working bite becomes a compressive stress, so that the pipe, the plug, the pipe, and the die come into contact with each other over the entire circumferential area within the same cross section as compared with drawing. For this reason, the pipe | tube becomes easy to smooth, and the pipe of high dimension precision can be obtained.

As a result, when the fatigue strengths of these tubes are compared, the pipes produced by compression can obtain sufficient target fatigue strengths as compared to the pipes produced by conventional drawing.

In addition, in the case of pressing, even if the shaft diameter is small, smoothing of the inner and outer surfaces of the tube is possible, so that the processing torsion does not increase as compared with the case of drawing, and thus the heat treatment load after the shaft reduction is light and the manufacturing cost is lowered.

In the press-fitting using the conventional rotary forging machine 8 shown in FIG. 3, since the die is rocked 12 and processed using the dividing die 9 which divided the integral type in the circumferential direction, a step difference arises and thickness precision is improved. On the other hand, in the present invention, such a step is not generated at all, and as a result, the inner and outer surfaces of the tube can be smoothed, so that sufficient fatigue strength can be obtained. In the present invention, for example, the die may be eliminated as a unitary die, or the step due to oscillation rotation may be prevented as a fixed die. Of course, you may prevent a step | piece as a die | dies and a fixed die | dye.

Furthermore, in the present invention, the device structure can be made simpler, a load sufficient for processing can be applied, and the exit side as compared with the thickness of the die inlet side, as compared with the conventional method of rocking a die using a rotary forging machine. Since sufficient processing is also possible with respect to the increase in load by making the thickness of the same or less, the dimensional accuracy is good for a wide range of required sizes, and a pipe with sufficient fatigue strength can be obtained.

Conventionally, as a method of making the outer diameter deviation, the inner diameter deviation, and the circumferential thickness deviation of the metal pipe to 3.0% or less, a method by machining (machining with partial removal of materials) is known, but the processing cost increases, The efficiency was also poor, and it was difficult to process a metal tube of small diameter with a long length. Therefore, it is difficult to apply to drive shafts and the like of automobile parts.

As a method of discriminating the machined metal tube and the present metal tube (the metal tube as pressed according to the present invention), black skin is formed on the surface of the metal tube by heating, rolling, or the like before the manufacturing process. Since the black skin is removed from the machined one, the method of observing the condition of the pipe surface is mentioned, and it can be identified by this method.

Moreover, this metal tube is several times superior in thickness variation compared with the method manufactured by the method of press-fitting a steel pipe into a die using a conventional rotary forging machine (for example, refer patent document 1, 2, 3). That is, in the past, any one or two or more of the outer diameter deviation, the inner diameter deviation, and the circumferential thickness deviation were 3.0% or less without being pressed.

In the present invention, the outer diameter deviation, the inner diameter deviation, and the circumferential thickness deviation as the index of the dimensional accuracy are obtained as follows.

The outer diameter (or inner diameter) deviation is a target outer diameter (or target inner diameter) from the circumferential distribution data of the outer diameter (or inner diameter) measured by rotating the tube by contacting the micrometer with the outer surface (or inner surface) of the tube. The maximum deviation with respect to the target outer diameter (or the target inner diameter) from the pipe and the laser oscillation source (distance from the circumferential distribution of the distance from the oscillation), which is calculated as the maximum deviation with respect to the laser beam Alternatively, the outer circumferential cross section of the tube may be imaged, and the deviation from the complete circle may be calculated in the circumferential direction to calculate the outer diameter (or inner diameter) deviation.

The circumferential thickness deviation is calculated as a difference between the circumferential distribution data of the outer diameter and the circumferential distribution data of the inner diameter, or by analyzing the circumferential cross section of the tube, the maximum deviation from the image of the thickness section to the target thickness. Measure directly as.

In addition, a measurement shall be made into the pitch of 10 mm or less at arbitrary positions except 150 mm at the line | wire end part of a pipe | tube, and is calculated | required as the value of a measuring point of 10 points or more.

That is, the outer diameter deviation, inner diameter deviation, and thickness deviation (= circumferential thickness deviation) are defined as follows.

Outer diameter deviation: (maximum outer diameter-minimum outer diameter) / target outer diameter (or average outer diameter) × 100 (%)

Inner diameter deviation: (maximum inner diameter-smallest inner diameter) / target inner diameter (or average inner diameter) × 100 (%)

Thickness deviation: (maximum thickness-minimum thickness) / target thickness (or average thickness) × 100 (%)

Since the high dimension precision tube of the present invention is a metal tube in which one or two or more of the above three dimensional accuracy indicators are 3.0% or less, it can be used as a metal tube such as an automotive drive system component that requires high precision of 3.0% or less. have.

In the conventional rotary forging press-fitting method shown in Figs. 3A and 3B, since the die 4 is used as the divided part and the swing 12 is used, the circumference under the step or die under high stress is used. The circumferential thickness deviation cannot be made sufficiently good due to the nonuniform deformation caused by the rigidity of the other dice in the direction.

In comparison with this, since the dies are integrally formed and do not need to be shaken by the compression of the present invention, nonuniform deformation does not occur, and as a result, the inner and outer surfaces of the tube can be smoothed.

Moreover, in the conventional rotary forging press-fitting method, it is essential to transfer the pipe 5 in conjunction with the swing 12 of the die 4, so that the swing speed cannot be raised above a certain limit from the impact load limit of the die. Low efficiency In addition, in conventional drawing, it is necessary to apply tension by tightly inserting the tip of the tube. Therefore, it is necessary to pull out the tube by pulling the end of the tube, so that it cannot be processed at once, and the processing efficiency is remarkably low.

On the other hand, in the present invention, the press is made and the plug is floated, so that the press input 15 is applied to the die inlet side by the pipe transfer means 3, and the feed can be continuously transferred in the die. Compared with the prior art, a very high efficiency machining is possible. In addition, the term "continuously conveying" as used herein refers to conveying a certain pipe 5 and a subsequent pipe 5 without interruption for a while, as shown in FIG. The form of moving in the direction may be an intermittent movement in which the continuous movement or the stop time is minimum.

Suitable pipe conveying means (3) includes a caterpillar (13) which catches the tube (5) before processing, a small piece of which catches the tube in an endless track; see FIG. 5), and the tube (5) before processing Endless belt 14 (refer to FIG. 6) for crimping, an intermittent conveyor (15, FIG. 7) for grasping a pipe before processing and intermittently transferring it, a press (not shown) for sequentially crimping a pipe before processing, and before processing And a hole roll 16 (see FIG. 8) for fitting a pipe. One or two or more of these may be combined to constitute the pipe conveying means 3.

The tube transfer means is optimally selected by the size (diameter, length, thickness) of the tube, the force required to press the tube, the length required for the tube after the press, etc., but it prevents defects when the tube is inserted or pressed. It is also important to secure the necessary pressure.

In addition, in the case of inserting a tube before processing into a hole-shaped roll, adopting a form using a hole roll of two or more rolls and / or a shape in which two holes or more of the hole rolls are provided can be used without causing defects in the tube. It is preferable because it is easy to secure.

In addition, when the plug is floated, it is stable because the plug is always present at a position where compressive stress is stably applied even when the compression conditions involving complicated angles of the die and plug, lubrication of the die and the plug surface, etc. vary. It is possible to obtain good dimensional accuracy.

In addition, in the manufacture of high precision precision tubes, lubrication between the plug outer surface and the tube inner surface, the die inner surface and the tube outer surface does not cause defects such as burn marks on the tube surface during processing. It can manufacture. Moreover, since frictional force is reduced by lubrication, the load required for processing can be reduced, processing energy can be saved, and production efficiency is also improved.

As a result of examining various lubrication methods, the inventors found the following method and made it a requirement of this invention. In other words, a lubricating film is formed on either or both of the inner and outer surfaces of the tube beforehand to perform the compression. As a lubricant used for formation of a lubricating film, any of a liquid lubricant, a grease type lubricant, and a dry resin is preferable. Examples of the liquid lubricants include mineral oils, synthetic esters, animal and vegetable fats and oils, and additives mixed therewith. Examples of the grease-based lubricant include Li-based grease lubricants, Na-based grease lubricants, and additives such as molybdenum disulfide. Examples of the dry resin include polyacrylic resins, epoxy resins, polyvinyl resins, polyester resins, and the like.

In the method of forming a lubricating film using the resin, the resin or the resin diluted with a solvent or an emulsion of the resin is applied to the tube. Subsequently, a method of being hit with hot air and drying or wind drying is preferable. Examples of the solvent for diluting the resin include ethyl, ketones, aromatic hydrocarbons, linear and branched hydrocarbons, and the like. As a dispersion medium for obtaining the emulsion of the said resin, water, alcohols, a mixture thereof, etc. are mentioned.

Moreover, in order to manufacture a highly efficient and high precision precision pipe | tube, what is necessary is just to process the electrically sealed steel pipe which the hot rolled steel plate was welded as it was, or the seamless steel pipe heated in the furnace as it is, without removing an oxidizing scale, In addition, the processing cost can be reduced.

In the conventional cold drawing and rotary forging press-fitting method, only the shaft diameter is processed. Only a unique size can be obtained from the same size of small pipe, and it is almost impossible to manufacture a pipe of the same outer diameter having a different workability. . On the other hand, in this invention, as shown in FIG. 1, the expansion pipe part 1A which expands the pipe | tube 4 to the plug 1, and the pipe | tube expanded 4 in cooperation with the die | dye 2 is shown. It was supposed that the shaft diameter portion 1B to be reduced in diameter was provided. Thereby, it becomes possible to manufacture the pipe of fixed size which differs in workability using the element pipe of the same size. Even if the size of the pipe after the elementary pipe and the pressing process is constant, not only the expansion rate due to the expansion part of the plug is decreased but also the reduction in the diameter ratio due to the shaft diameter part of the plug inevitably increases and decreases. Because the degree will be different.

Expansion rate = 1-DO / D1

Shaft Diameter = 1-D2 / D1

but,

DO: outer diameter of the jurisdiction,

D1: Target outer diameter after expansion

D2: Target outside diameter after shaft diameter

Moreover, in this invention, it is preferable to supply a pipe continuously to a die from a viewpoint of improving manufacturing efficiency. In such a case, if the plug is supported from the die inlet side or the outlet side, a means such as a bar, a wire, or the like used for the support becomes an obstacle, and it becomes difficult to continuously supply the pipe. Therefore, the plug is preferably floated in the tube.

In addition, in order to stably perform the compression of the present invention, it is necessary to stabilize the plug during processing. In other words, it is necessary to prevent deviation from an appropriate position with respect to the dice.

This point was examined. The plug is subjected to surface pressure from the pipe by expansion pipe and shaft diameter. It was found that when the surface pressure on the shaft diameter side is made larger than that on the enlarged diameter side, the plug can be stabilized. In order to make the surface pressure on the shaft diameter side larger than that on the expansion diameter side, one shows that the tapered angle θA of the expansion pipe portion 1A of the plug 1 is the tapered angle of the shaft diameter portion 1B. It is effective to set it as less than (theta) B. Here, the tapered angle of the part of a plug means the angle which consists of the straight line 17 parallel to the plug central axis which follows the surface of the part and the advancing direction of a pipe | tube. Moreover, Preferably, it is (theta) A = 0.3-35 degrees and (theta) B = 3-45 degrees. In addition, the shaft diameter may be made larger than the expansion ratio, and for this purpose, it is effective to make the outside diameter of the exit of the die less than the outside diameter of the inlet.

In the present invention, since an integrated fixed die can be used, no step or unilateral deformation due to die division occurs at all. As a result, the inner surface of the tube and the outer surface of the tube can also be smoothed. Moreover, by using an integrated fixed die, a load sufficient for processing can be applied. By setting the thickness of the die outlet side to be equal to or smaller than the thickness of the same inlet side, it is possible to sufficiently process even if the load increases. As a result, a pipe with good dimensional accuracy can be obtained. The range of product canal sizes that can be manufactured from one canal size is expanded.

However, in order to stabilize the press working, it is necessary to use a plug and a die satisfying the requirements found by the inventors. The requirement is that the angle of the surface of the shaft diameter portion of the plug to the machining center axis (the angle of the plug shaft diameter) is 5 to 40 °, and the length of the same portion (the length of the plug shaft diameter portion) is 5 to 100 nm. The angle (: dice angle) which the inner surface of the hole on the inlet side of the die forms with the machining center axis is set to 5 to 40 degrees. Preferably, the length of the bearing portion of the plug (the length of the plug bearing portion) is 5 to 200 mm. Here, the machining center axis means an axis perpendicular to the radial cross section of the plug in the plug, moreover, an axis passing through the center of the same cross section, and an axis perpendicular to the radial cross section of the die hole in the die, and further passing through the center of the same cross section. The bearing portion means the circumferential portion leading to the minimum diameter portion of the shaft diameter portion.

The reason for defining the plug and die as described above is as follows.

(Plug shaft diameter angle = 5 to 40 °)

If the plug shaft diameter angle is less than 5 °, the plug may come out with the material (: tube). On the other hand, if the plug shaft diameter angle exceeds 40 °, the plug and the material may be blocked by the die and pressed. There may be no.

(Plug Shaft Diameter = 5-100mm)

If the length of the plug shaft portion is less than 5 mm, the plug may come out together with the material. On the other hand, if the plug shaft diameter portion exceeds the length of 100 mm, the friction force between the plug and the material increases, and both sides of the die are clogged and pressed. It may become impossible.

(Dice angle = 5-40 degrees)

If the die angle is less than 5 °, the plug may be stuck with the material while the plug is stuck in the material. On the other hand, if the die angle is over 40 °, the plug and the material may be blocked by the die and may not be able to be pressed. .

(Plug bearing part length: 5 ~ 200mm)

The force acting on the plug to be pulled out to the die inlet side due to the material applied to the shaft diameter and the reaction force from the die is acted on. However, the plug must be balanced to exert a force to extrude the plug to the die outlet side to stabilize the plug. It is good to use a frictional force acting on this surface by providing a bearing part in a plug. In consideration of the inventors, in order to contribute to the sufficient stabilization of the plug, the frictional force of the plug bearing portion may be 5 to 200 mm. When the length of the plug bearing portion is less than 5 mm, the friction force for extruding the plug is insufficient, and the plug is easily returned to the die inlet side by the reaction force of the material and the die. On the other hand, when the length of the plug bearing portion exceeds 200 mm, the friction force is too large, and the plug It becomes easy to be extruded to the die | dye exit side, and both the plug positions become unstable.

In the present invention, the plug can be floated so that the plug can always be positioned at a position where a stable compressive stress state can be obtained even if the compression conditions involving complicated angles of dies and plugs, lubrication of their surfaces, etc. are varied. have. In addition, when the thickness at the die exit side is set at or below the thickness at the inlet side, it is preferable because the stability of the pressing process is further improved.

When press-molding, the plug is blocked by the pipe and the load increases, and as a result, the press-fitted element pipe may be buckled and the machining may not be possible. It is necessary. There, the present inventors paid attention to the load at the time of the pressing. In other words, if the plug is blocked, the load in the pressing processing direction is remarkably increased. If the load is below a certain value, the pressing is possible. If the plug is exceeded, the pressing is impossible and the pressing condition is optimized. It would be nice to change it. This specific value is called the limiting load of compression.

When the compression is impossible, the element pipe to be pressed is buckled. Therefore, if the pressure limit load is set from the equation indicating the buckling of the pipe, the load can be stably pressed at a load below this. The expression of the buckling of the tube is well known by the Euler equation obtained from the modulus of elasticity of the material. However, the present inventors have shown that the value is far from the actual phenomenon and cannot be applied at all. Therefore, as a result of examining this and other various buckling equations, it was found that the following Equation 4 best represents the actual phenomenon.

[Equation 4] σ _k × elementary pipe cross-sectional area

From here,

σ _k = YS × (1-a × λ),

λ = (L / √n) / k,

a = 0.00185-0.0155,

L: Tube length,

k: section secondary radius,

k ² = (d ₁ ² + d ₂ ² ) / 16,

n: tube end state (n = 0.25 to 4),

d ₁ : outer diameter of the pipe

d ₂ : bore diameter

YS: yield strength

In order to make it possible to stably press, if the measured load (measurement load) does not exceed the value (calculated load) of Equation 4, the press may be continued as it is. It is good to stop once, change conditions, and resume pressurization.

However, Equation 4 is slightly complicated, and when it is intended to make the judgment more simply, Equation 5 can be used after simplifying Equation 4.

Yield strength YS × tube cross-sectional area of tube

Equation 5 shows a maximum limit load at about 10 times than Equation 4, but the present inventors have grasped that it can be sufficiently determined simply.

In the case of pressurizing a remarkably short pipe (for example, about 0.2 m or less), or increasing the load to a degree where the die does not crack even if the pipe is slightly buckled, the load may be processed at once. Equation 6 may be used.

Equation 6 Tensile strength TS of element pipe

Further, the measuring load (actual load in the pressing direction) may be measured by using a load cell installed in the punch of the pressing, or by floating a die from the mount and the die and the die. The method of measuring with one load cell is preferable.

In addition, as a measure when the measured load exceeds the calculated load calculated by any of Equations 4 to 6, that is, when it is determined that it cannot be processed, the indentation is stopped once, and the die and / or plug are placed in the same product dimension. After replacing with the one of a corresponding other shape, processing may be resumed. Here, since dies and / or plugs of different shapes corresponding to the same product size are for processing the same element pipe, they may be selected from those set at the same shaft diameter.

Moreover, in order to make more stable processing conditions, it was found by the present inventors that it is suitable to make the angle (refer FIG. 10) of the dice and plug used after replacement smaller than that before replacement.

Moreover, in order to make it the conditions which can be processed stably, what kind of lubricant apply | coats to an element pipe may be changed. However, when the lubricant is applied by the method of immersing the element pipe in the lubricant in the coating container from the point of simplicity, it is difficult to change the type at a high frequency because it takes time to replace the lubricant in the coating container. Therefore, as a lubricant, it is important to experiment and select in advance that the performance which can significantly reduce the load of a press processing direction is good.

In comparison with this, in the case of the pressurization which concerns on this invention, as shown in FIG. 1, the plug 1 is inserted in the pipe 4, the pipe 4 is pressed in the hole of the die | dye 2, and it passes. Let's do it. Here, the plug is in contact with the entire circumference of the tube inner surface inside the machining bite, and the hole is in contact with the entire circumference of the tube outer surface inside the machining bite. Due to the pressing force 11 applied to the inlet side of the die 2, the compressive stress acts on the entire surface inside the machining bite. As a result, the pipe 4 can fully contact the plug 1 and the die 2 on either the inlet side or the outlet side in the machining bite. Moreover, even at a slight shaft diameter, the inside of the machining bite becomes a compressive stress, so that the tube, the plug, the tube, and the die are more easily in contact with each other than the drawing, and the tube is easy to be smoothed, so that a tube of high precision can be obtained. have. In addition, in the case of pressing, even if the shaft diameter is small, the inner and outer surfaces of the tube can be smoothed, and the processing torsion is smaller than that of the drawing, so the heat treatment load after the shaft diameter is also light, or the heat treatment can be omitted, and the manufacturing cost is lowered. .

Therefore, the structure of the apparatus of this invention is the same pipe | tube as the die | dye 2 which has the plug 1 which can contact the whole inner surface circumference of the metal tube 4, and the hole which can contact the whole outer surface circumference of the same tube 4, (4) has a tube presser 3 for crimping, and the metal tube 4 is pressed into the hole of the die 2 with the tube presser 3 while the plug 1 is inserted into the tube. It is characterized by enabling the pressurization.

In addition, in the press-fitting using the conventional rotary forging machine 8 shown in FIG. 3, the dividing die 9 is rocked 12 using the dividing dice 9 which divided the integral type in the circumferential direction. Therefore, uneven deformation occurs due to the stiffness of the other dice in the circumferential direction under the step by division or high stress, so that the thickness precision cannot be sufficiently satisfactorily performed. On the other hand, in the apparatus which is configured to be capable of pressurization of the present invention, since a metal tube is passed through a hole of a die having a hole in contact with the entire circumference of the tube outer surface within the same cross section, there is no level difference such as that caused by a split die. As a result, the inner and outer surfaces of the tube can also be smoothed.

Furthermore, in the present invention, an integrated fixed dice is used as the dice. The apparatus structure can be made simpler as compared to the method using a split die mounted on a conventional rotary forging machine. Even if a load sufficient for processing can be applied and the load increases with the thickness on the outlet side being equal to or less than the thickness on the die inlet side, the processing can be sufficiently performed. A metal tube with remarkably good dimensional accuracy can be obtained for a wide range of required product sizes.

In the present invention, the plug is floated. Even when the compression conditions such as the angle of the die and the plug, the lubrication of the die and the plug surface, and the like are complicated, the plug is always located in a place where the compression stress is stably applied. For this reason, it is possible to stably obtain good dimensional accuracy.

Moreover, in the conventional drawing, it is necessary to pull the tip of the tube and pull out the portion thereof, so that the tube cannot be processed at once. On the other hand, in the present invention, since the tube is pressed, it is not necessary to pinch the tip of the tube, and the tube can be pressed as it is. When the plug is floated, it is possible to press continuously and the productivity is remarkably improved. In addition, when the length of the tube is short, by employing an intermittent crimping operation as the tube press, it is possible to maintain high productivity and produce a high-precision precision tube. Further, the tube press may support and press the trunk portion of the tube and press one end of the tube.

Tubes that require compression have a wide variety of product dimensions. In pressurization, in order to change the outer diameter of a product, you need to prepare a die with a different hole shape, and replace a die every time the outer diameter of a product changes. In addition, the bore size of a die is usually represented by diameter, angle, and tapered length.

However, the outer diameter of the product differs from minute to lot by at least a few tons, and every time the change is made, it is necessary to remove the used die and install the next used die, but the accuracy of the installation of the die is ± 0.1. Due to its strictness in mm, it required considerable time and labor.

In order to reduce the time and labor of this die exchange, the present inventors have found that various dies of different hole shapes according to the outer diameter of the product may be prepared, and these may be replaced in parallel.

In the manufacturing method of the high precision precision pipe | tube which inserts and floats a plug in a pipe | tube, and presses the pipe | tube to press and pass the die continuously or intermittently, the dice | dies of different hole shape are arrange | positioned on the same circumference. Only the dies of the hole type according to the target product dimensions are rotated in the circumferential direction of the array and placed in the pass line to be used for pressing. In the case where the target product size of the next pipe is different from the previous pipe, the die of the hole type according to the outside diameter may be similarly rotated and disposed in the pass line to be used for compression.

For example, as shown in FIG. 11, the die 2 which passes the tube 4, the indenter 2 which press-fits the tube 4 to the dice 2 in a pass line, and a plurality of, The dice 2, 20, ..., 20 are supported in the form of being arranged on the same circumference and conveyed in the circumferential direction. It can be performed easily using the apparatus which has the die swivel 19 which arrange | positions any one dice | dies 2 in a pass line.

In addition, one die may be arranged in the same straight line with a plurality of dies having different hole shapes, and any one of these dice may be moved in the straight line of the arrangement according to the product size and placed in a pass line to be used for pressurization. .

This includes, for example, a die 2 through which the tube 4 passes, a press-fit machine 2 for pressing the tube 4 into the die 3 in the pass line, and a plurality of dice 2 as shown in FIG. , 20, ..., 20 are supported in the form of being arranged in the same straight line and conveyed in the straight direction. It can be performed easily by using the apparatus which has the dice straight stage 23 which arrange | positions any one dice | dies 2 in a pass line.

In addition, it is necessary to efficiently perform charging of the plug. If the plug can also be easily replaced during the die exchange, the efficiency is further improved. Since the plug 1 used in the previous processing is left in the die, it is removed with the exchange of the die. What is necessary is just to be able to insert the plug 22 required for the next process into a pipe | tube during the exchange of dice.

To this end, in any of the first and second methods of the present invention described above, in changing the product dimensions between the preceding pipe and the next pipe, after the end of the compression of the previous pipe, the next pipe is placed on the die inlet side. Stop it. Before or after the movement of the die according to the product dimension of the next tube, it is preferable to insert the plug 22 according to the same product dimension into the next tube. As a result, not only dice but also plugs can be efficiently exchanged.

When the pressing is performed, the pipe on the die exit side is likely to bend. If the tube is bent, the tube is not a product, so a technique is required to process the tube so that it is not bent. In conventional drawing, processing is performed while the tension is added one by one by inserting the tip of the pipe on the die exit side. However, the processing efficiency is low, but the pipe is guided in the drawing direction, making it difficult to bend. However, in the case of pressurization, the pipe on the die exit side is free to move, and the pipe is easily bent due to the processing accuracy of the die, the thickness precision and surface state of the pipe before processing, and the lubrication nonuniformity of the die and the plug. For this reason, the technique which prevents the bending of the pipe | tube by the die | dye exit side was desired intensely.

Therefore, the inventors conducted an experiment in which a guide cylinder was provided at the inlet side and the outlet side of the die and guided through the tube for bending of the tube after the compression. If the guide tube is installed on either the inlet side or the outlet side of the die, the tube becomes difficult to bend, and when installed on both sides, the tube becomes more difficult to bend, and the position of the guide tube is closer to the die outlet. The harder it becomes to bend.

Therefore, what is necessary is just to provide a guide cylinder in the immediate vicinity of the die inlet side and the die outlet side. That is, it is good to install in the die exit side very close to die. However, it turned out that bending can not be prevented fully depending on the bending direction of a pipe | tube. In order to prevent bending sufficiently regardless of the bending direction of the pipe, the gap between the outside of the pipe and the inside of the guide tube should be made almost zero. However, it has been found that there is a problem that the tube is in excessive contact with the guide barrel, so that a defect occurs or the pushing force is significantly increased.

The inventors have found that the bending of the tube has already begun immediately near the die exit side. In other words, the residual stress is generated in the tube due to the accuracy of die processing, the thickness accuracy and surface condition of the tube before processing, and the lubrication unevenness of the die and the plug, and the residual stress is rapidly released immediately near the die exit. This is easy to occur. Therefore, by providing means for fine-adjusting the bending direction of the tube in the immediate vicinity of the die outlet side, the bending of the tube can be sufficiently prevented.

As a result of earnestly examining by the present inventors, a hole type for passing a tube, a support substrate for movably supporting the hole type in a plane orthogonal to a clearance direction, and a support substrate are provided in the immediate vicinity of the die exit side. And a pipe bending fine adjustment means having a hole type moving mechanism for moving the hole type. The tube of the die exit side is sufficiently passed through the hole of the hole type in which the in-plane position orthogonal to the clearance direction is finely moved in the support substrate surface by using the hole moving mechanism to make a small movement. I figured out what can be prevented.

In order to finely adjust the hole position, for example, a plurality of dummy tubes are used before actual production, and a bending experiment in which the hole position is changed by several points is performed to measure the bending of the tube, and the amount of change in the hole position and the Find the relationship with the amount of change in the bend of the tube. If the bending of the pipe is likely to exceed a predetermined threshold at the time of actual production, the method of moving the hole shape in the direction in which the bending becomes smaller based on the above relationship is preferable.

As a hole-type moving mechanism, the method of crimping | compressing one or two or more places of a hole outer peripheral part in the direction orthogonal to a clearance direction through the tapered surface of the wedge-shaped metal mold made to move to a clearance direction with a screw, for example is preferable. Or, for example, it is preferable to press or pull one place or two or more places of the outer periphery of the hole-type outer periphery in a direction orthogonal to the clearance direction directly with a hydraulic cylinder (hydraulic cylinder, air cylinder, etc.).

The hole diameter of the hole shape is preferably equal to or larger than the exit hole diameter of the die, so that the pipe can be processed smoothly without being blocked at the die exit side during the pressing process. In particular, since fine adjustment is easy in the exit hole diameter of die | dye +3 mm within 3 mm, it is more preferable. Furthermore, the hole of the hole shape may be a straight hole or may be a tapered hole.

Moreover, of course, the support substrate is provided with a hollow portion having a size that allows the same tube to pass through a sufficient gap at a position intersecting the passage of the tube exiting the die.

Also, at the inlet side of the die and / or the pipe bend adjusting means outlet side, when a guide tube is passed through the pipe entering the die and / or the pipe from the pipe bend fine adjusting means, the tube enters the die almost vertically, and And / or almost vertically from the tube bending fine adjustment means, which is preferable because it is easier to prevent bending of the tube.

Moreover, in this invention, it is preferable to transfer a pipe continuously and to press in a die. By continuously conveying the pipes, the frictional heat and the processing heat generated by the dies and the plugs are stabilized as compared with the case where the pipes are processed at one time. Therefore, the bending can be more easily prevented. Moreover, in the pressing process, as in the case of drawing, the soldering process for holding the pipe end to the drawer on the die exit side is unnecessary, so that the production efficiency can be increased by continuously feeding the end of the preceding pipe into the shape of the subsequent pipe. There is a number.

In the case of the conventional drawing, sufficient lubricating film is required in order to obtain high dimension precision, and the bonding process with favorable lubrication was performed for that reason. In this method, the tube is pickled in advance to remove the oxidized scale, and further, an alkaline wash is performed to further neutralize the acid, followed by further washing with water. Thereafter, the tube was immersed in a container subjected to the bonding treatment to form a lubricating film. The film was then farmed in a container of metal soap to form a film, and the tube was then dried by hot air. Therefore, these processes require several hours or more, and when these processes are remarkably impeded to the heat of the facility which draws out the pipes, the productivity is remarkably impaired.

On the other hand, according to the pressing process, even if the axial diameter is small, high dimensional accuracy is easily obtained, so that the lubrication of the pipe may be simple. In other words, the pipes may not be pickled, and the hot air may be dried only after immersion of the lubricant. However, in order to continue pressurization, the squareness of the cross section of a pipe | tube is important, and the grinding apparatus for obtaining this squareness is necessary.

It is most efficient to carry out these treatments before press-processing in order of obtaining the squareness of a pipe cross section, lubricating agent immersion cloth, and drying. In view of these points, in the present invention, a pipe section grinding device for grinding the pipe cross section at right angles to the tube axial direction, a lubricant dipping container for impregnating lubricant on the pipe, and a drying device for drying the pipe coated with lubricant In this order, as the heat of equipment arranged on the inlet side of the press-working apparatus, high-precision precision tubes can be efficiently manufactured.

In addition, since it is more efficient to obtain the squareness of the pipe cross section immediately after cutting the pipe into short lengths, the equipment heat of the present invention cuts the pipe into short lengths on the inlet side of the pipe cross section grinding device. It is preferable to arrange a cutting device.

In addition, if a lubricant which is easy to form a film by drying is applied, instead of being immersed and dried on the inlet side of the pressing apparatus, it is also possible to apply spraying immediately after the die inlet side in the pressing apparatus and then dry it. If the lubricity is better, or the lubricity is better, drying may be omitted and the tube may be pressed in a wet state. Therefore, the equipment heat of the present invention is changed to the lubricant immersion coating container and the drying apparatus, and the lubricant injection coating apparatus for spraying lubricant onto the die inlet side of the press processing apparatus, or the lubricant is sprayed onto the tube. A lubricant spray coating and drying apparatus may be arranged after the drying.

In addition, in order to further improve the efficiency of the press working, it is preferable that the die and the plug can be easily exchanged online, and the pipe is not bent at the die exit side. From these points of view, in the facility heat of the present invention, the die exchanger is installed in the press processing device to replace the die, the plug exchanger for replacing the plug, and the bending to prevent bending of the pipe on the die exit side. It is preferable to arrange | position one or two or more of prevention devices.

It is preferable that the die (or plug) changer is configured such that dies (or plugs) having a plurality of different dimensions (and / or shapes) are arranged and used in order of use, and are sequentially configured to be transported to a position in a predetermined clearance line. Do. The bending prevention device is configured to be capable of acting in a direction opposite to the direction in which the tube is intended to be bent with respect to the tube immediately near the die exit side using, for example, a movable disc (Disc) having a passage hole of the tube. desirable.

Moreover, since the drawing used conventionally, the drawing used in the present invention, and the pipe of the surface pickled after processing are often required, it may be pickled and shipped in a separate process. In the case of drawing, in the bonding treatment before processing, it is necessary to pickle pipes in order to form a strong film of the lubricant. Furthermore, after drawing, pickling is necessary again to remove the lubricant, and then pickling twice. Should be. On the other hand, in the case of pressurization, the lubrication treatment before processing can be simple and the oxidation scale can be attached, so that the lubrication treatment can be brought online and assembled into the equipment heat, and the equipment heat is efficient at low cost. This becomes possible.

Example 1

Hereinafter, an Example is given and this invention is demonstrated further more concretely.

In Example 1.1, the pressing process of the form shown in FIG. 1 was performed with respect to the steel pipe of external diameter 40mm x thickness 6mm. Here, the plug which used the mirror surface as the surface made to contact a pipe | tube, and the die which made the mirror surface the surface made to contact a pipe outer surface as an integrated fixed die were used. The plug was inserted into the tube with one end fixed. Processing conditions were made into exit thickness = inlet thickness, and shaft diameter = 10%.

In Example 1.2, processing was carried out in the same manner as in Example 1.1 except that the shaft diameter ratio was 5%.

In Example 1.3, the process was carried out in the same manner as in Example 1.2 except that the plug was floated.

In addition, in Comparative Example 1, instead of the pressurization of the form shown in FIG. 1, the drawing was carried out in the same manner as in FIG.

In Comparative Example 2, instead of the integral fixed die in Example 1.2, the divided dice of the form shown in Fig. 3 were assembled into a rotary forging machine and used by swinging. Processing was performed.

In Comparative Example 3, the processing conditions were performed in the same manner as in Comparative Example 2 except that the processing conditions were set to the exit thickness = the inlet thickness + 1 mm (= 7 mm).

The three dimensional accuracy indicators were obtained for these steel pipes after shaft diameter machining, and these steel pipes were subjected to the fatigue test. The results are shown in Table 1.

Moreover, the outer diameter and inner diameter deviation shown in Table 1 were calculated | required by the measurement using the said laser beam, and the circumferential thickness deviation of the same table was calculated | required from the difference of the circumferential distribution of these measurement data.

In addition, the endurance limit recovery of the fatigue test shown in Table 1 is a test for obtaining a constant number of stresses (i.e., endurance recovery) until a crack is generated by keeping the stress constant, thereby changing the stress level in various ways. In the diagram illustrating the relationship between the and the endurance recovery, the endurance recovery at the bending point at which the stress starts to become substantially constant from the decreasing direction as the endurance recovery increases, the higher the value, the better the fatigue strength. In other words, in this example, it is the endurance recovery at a stress of about 150 MPa.

According to Table 1, the product tubes of Examples 1.1 to 1.3 had a remarkably good dimensional accuracy, the best fatigue strength, and especially when the plug was floated, the dimensional precision was better (Example 1.3). On the other hand, in the conventional drawing, the dimensional accuracy of the product pipe is lowered, and as a result, the fatigue strength is significantly lowered (Comparative Example 1). Even in the indentation using a rotary forging machine, the dimensional accuracy of the product pipe was lowered (Comparative Example 2), and when the thickness was increased, the thickness was further lowered (Comparative Example 3), and sufficient fatigue strength could not be obtained.

Example 2

As an example of the present invention, a steel pipe having a diameter of 40 mm x 6 mm t x 5.5 mm L is used as a material, and the plug is floated into a steel pipe by using a mirror-shaped plug and an integrated fixed die, and the steel pipe is inserted at the die inlet side at an axis diameter of 5%. Pressing was performed with the steel pipe thickness on the die exit side being 6 mm t as the die inlet side. In addition, an intermittent feeder of the form shown in Fig. 7 was used as the pipe conveying means so that the pipe was continuously conveyed in the die.

In addition, as Comparative Example 1, drawing in the form of FIG. 2 was performed. In this example, using the above-described steel pipe as a material, the plug is inserted into the steel pipe using the plug and die as described above, the steel pipe is pulled from the die outlet side at the shaft diameter as described above, The steel pipe thickness was reduced to 5.5 mm t.

As Comparative Example 2, a rotary forging press-fitting method in the form of Figs. 3A and 3B was performed.

In this example, the above-mentioned steel pipe is used as a raw material, and a rotary forging machine using a split die is used instead of the integrated fixed die, and the plug as described above is inserted into the steel pipe, and rotary forging press-in at the shaft diameter as described above is performed. To increase the thickness of the steel pipe on the outlet side of the same forging machine to 7 mm t.

The dimensional accuracy (outer diameter deviation, inner diameter deviation, and circumferential thickness deviation) of the steel pipe manufactured by the method of each of these examples was measured, and the processing efficiency was further investigated. The results are shown in Table 2. In addition, the outer diameter deviation and the inner diameter deviation were obtained by image analysis of the circumferential cross section of the tube and calculating the deviation from a complete circle in the circumferential direction. In addition, the circumferential thickness deviation was directly measured as the maximum deviation with respect to the average thickness from the image of the thickness cross section by analyzing the circumferential cross section of the pipe.

According to Table 2, the steel pipe manufactured by the compression of the example of this invention was remarkably good in dimensional precision, and the processing efficiency was also favorable. On the other hand, in the steel pipe manufactured by the drawing of the comparative example 1, dimensional precision fell. Moreover, also in the steel pipe manufactured by the rotary forging press injection of the comparative example 2, dimensional precision fell. In addition, processing efficiency was remarkably low with drawing and rotary forging indentation.

Example 3

[Comparative Example 3.1] A φ40 mm × 6.0 mm t × 5.5 mm L-sealed steel tube with a hot rolled scale attached to its surface was processed under the following condition A by the compression shown in FIG. 1.

(Condition A) Plug: A mirror plug is inserted into a steel pipe and floated.

         Dies: integrated fixed dice

         Shaft diameter: 5%

         Steel pipe thickness at die exit: 6.Omm t (= thickness at inlet)

[Invention Example 3.1] The steel pipe as described above was applied to a liquid lubricant (mineral oil) on both inside and outside thereof to form a lubricating film, and then processed as in Comparative Example 1.

[Inventive Example 3.2] After the steel pipes as described above were coated with grease-based lubricants (molybdenum sulfide added to Li-based greases) on both sides of the steel pipes to form a lubricating film, they were processed as in Comparative Example 1. It was.

[Inventive Example 3.3] The steel pipes described above were coated with a drying resin (polyalkyl resin) on both sides of the steel pipe and dried to meet the hot air (about 200 ° C.) to form a lubricating film. Processed as follows.

[Example 3.4 of the Invention] The steel pipe as described above was lubricated by applying a liquid diluted with a dry resin (polyalkyl resin) with a solvent (acetone) on both inside and outside thereof, and then dried by lubrication with warm air (about 50 ° C). After forming a film, it processed like the comparative example 1.

[Inventive Example 3.5] The above-described steel pipe was coated with an emulsion obtained by dispersing a dry resin (polyalkyl resin) in a dispersion medium (water) on both inner and outer surfaces thereof, and then dried and lubricated by warm air (about 70 ° C). After forming a film, it processed like the comparative example 1.

[Comparative Example 3.2] The steel pipe as described above was coated on the both inside and outside thereof to form a lubricating film by applying the same liquid lubricant as in Example 1, and then processed under the following condition B by the cold drawing method shown in FIG.

(Condition B) Plug, die, shaft diameter: same as condition A respectively

         Steel pipe thickness at the die exit side: 5.5 mm t (<inlet side thickness)

[Comparative Example 3.3] The steel pipe as described above was coated on the inner and outer surfaces thereof with a liquid lubricant as in the present invention 1 to form a lubricating film, and then processed under the following condition C by the rotary forging indentation method shown in FIG. .

(Condition C) Plug: same as Condition A

         Dies: Split dice

         Shaft diameter: same as condition A

         Steel pipe thickness at the die exit side: 7.0mm t (> inlet shaft thickness)

Table 3 shows the results of measuring the state of surface defects and the dimensional accuracy (outer diameter deviation, inner diameter deviation, thickness deviation) of the steel pipes produced by the methods of each of these columns. Furthermore, the outer diameter deviation and the inner diameter deviation can be determined by analyzing the circumferential cross section of the tube and calculating the maximum deviation from the complete circle (i.e., (maximum diameter-minimum diameter) / full circle diameter x 100%) in the circumferential direction. It was. In addition, the thickness deviation was measured directly as the maximum deviation (namely, (maximum thickness-minimum thickness) / average thickness x 100%) with respect to the average thickness from the image of the circumferential cross section of the tube.

According to Table 3, in the examples of the present invention which were pressed under lubrication, no defects occurred at all on the surface of the steel pipe after processing, good surface quality was obtained, and dimensional accuracy was remarkably good. In contrast, in Comparative Example 1 in which the compression was performed under no lubrication, defects occurred on the surface of the steel pipe after processing. In the comparative example 2 which performed the process by cold drawing under lubrication, dimensional precision fell. In the comparative example 3 which processed by the rotary forging press method under lubrication, the dimensional precision fell further.

In addition, in the present Example, although the case of so-called double-sided lubrication which provided the lubricating film in both the inside and the outside of the pipe | tube was shown, this invention is not limited to this, The so-called one surface which forms a lubricating film in any one of an inner surface and an outer surface. The case of lubrication is also included, and it is clear that in this case of lubrication on one side, the occurrence of a defect on the surface on which the lubrication film is formed can be effectively prevented.

Example 4

[Example of the Invention]

The tube was expanded by the present invention (: pressurization using a plug capable of expansion pipe and shaft diameter) outlined in FIG. 1, using a steel pipe having a diameter of 40 mm x 6.Omm t x 5.5 millimeter L, followed by shaft diameter processing. The target thickness on the die exit side was 6.Omm t as in the inlet side. The plug was floated in the tube with mirror finish. The die used the integrated fixed dice which mirror-treated the die inner surface. The expansion ratio of the plug, the shaft diameter ratio, the tapered angles θA and θB of the expansion pipe portion and the shaft diameter portion, and the target outer diameter D2 of the pipe on the die outlet side (after the shaft diameter) were set to the values shown in Table 4 for each of the examples. The tube was fed continuously to the dice.

Comparative Example A

The tube as described above was subjected to shaft diameter processing by cold drawing (only shaft diameter possible) shown in FIG. 2. The target thickness on the die exit side was 6.0 mm t as on the inlet side. The plug was floated in the tube with mirror finish. The die used the integrated fixed dice which mirror-treated the die inner surface.

The shaft diameter of the plug and the target outer diameter of the pipe on the die exit side were set to the values shown in Table 4 for each of the examples. The tube was fed continuously to the dice.

[Comparative Example B]

The element pipe as described above was subjected to shaft diameter machining by the rotary forging press method shown in FIG. 3 (only shaft diameter is possible). The target thickness on the die exit side was 6.0 mm t as on the inlet side. The plug was floated in the tube with mirror finish. The dice | dies used the dividing dice which mirror-treated the die inner surface. The shaft diameter of the plug and the target outer diameter of the pipe on the die exit side were set to the values shown in Table 4 for each of the examples. The tube was fed continuously to the dice.

Dimensional precision (outer diameter deviation, inner diameter deviation, thickness deviation) was measured about the steel pipe manufactured on the conditions of each of these examples. The outer diameter deviation and the inner diameter deviation were obtained by image analysis of the circumferential cross section of the tube, and calculating the maximum deviation from the complete circle (i.e., (maximum diameter-minimum diameter) / complete circle diameter x 100%) in the circumferential direction. In addition, the thickness deviation was directly measured as the maximum deviation (namely, (maximum thickness-minimum thickness) / average thickness x 100%) with respect to the average thickness from the image of the thickness cross section by image analysis of the circumferential cross section of the tube. In addition, the cross-sectional hardness was measured as an index of workability. In addition, the average outer diameter and the average thickness of the tube after processing which were obtained simultaneously with the measurement of the said dimensional precision were employ | adopted as an index for judging whether the tube of a fixed size can be obtained after a process. These results are shown in Table 4.

According to Table 4, in the examples of the present invention, the dimensional accuracy after the machining was remarkably good, and by changing the knitting of the plug and the die, a tube having a constant size and a different degree of workability could be obtained. In contrast, in the comparative example, when the dimensional accuracy was lowered and a pipe with a different degree of workability was obtained from the same size pipe, it was not possible to obtain an outer diameter and a thickness of a constant size. In addition, in the example of this invention which satisfy | fills either or both of (theta) A <(theta) B, D2 <DO, the floating state of the plug in a pipe was further stabilized.

Moreover, expansion rate a (%) = (D1-DO) / D1 × 100

        Shaft Diameter b (%) = (D1-D2) / D1 × 100

Example 5

(Invention Examples 5.1 to 5.4)

Using an electric pipe with an outer diameter of 40 mm x thickness of 6 mm as a primary pipe, press-molding shown in FIG. 1 was performed using a mirror plug and a fixed die. Table 5 shows the shape conditions (plug shaft diameter part, plug shaft diameter part, plug bearing part length, and die angle) of the used plug and die. The plug was floated in the tube. The thickness of the pipe on the die exit side was set to 5 mm.

(Comparative Examples 5.1 to 5.4)

As shown in Table 5, the shape conditions of the plugs and dies used with the steel pipes of the lot as the base pipes as the example of the present invention were changed as shown in Table 5, except that the pressing process was performed in the same manner as the example of the present invention.

(Priority Example 5.1)

The steel pipe of the lot like the example of this invention was made into the primary pipe | tube, and the process by the cold drawing shown in FIG. 2 was implemented using the mirror-shaped plug and the fixed die | dye. Table 5 shows the shape conditions of the used plug and die. The plug floated in the pipe. The thickness of the pipe on the dice outlet side was set to 5 mm.

(Prior Example 5.2)

The copper tube of the lot as the example of this invention was made into a pipe, and the process by the rotary forging-indentation method shown to FIG. 3A and 3B was performed using the rotary forging machine equipped with the mirror plug and the split die. Table 5 shows the shape conditions of the used plug and die. The plug was floated in the tube. The thickness of the tube on the die exit side was increased to 7 mm.

Table 5 shows the dimensional accuracy (thickness deviation, inner diameter deviation, and outer diameter deviation) measured for the production pipe in the method of each of the above examples, and for the product tube in the case of production. Here, the outer diameter deviation and the inner diameter deviation are obtained by analyzing the circumferential cross section of the tube and calculating the maximum deviation from the complete circle (i.e., (maximum diameter-minimum diameter) / complete circle diameter x 100%) in the circumferential direction. Obtained. In addition, the thickness deviation was directly measured as the maximum deviation (namely, (maximum thickness-minimum thickness) / average thickness x 100%) with respect to the average thickness from the image of the thickness cross section by image analysis of the circumferential cross section of the tube.

According to Table 5, in the present invention, it was possible to stably complete the pressing process, and the dimensional accuracy of the product tube was remarkably good. On the other hand, in the comparative example, neither press processing could be completed and a product tube could not be obtained. In addition, in the conventional example, although the process was completed, the dimensional precision of a product pipe | tube fell.

Example 6

Example 6.1

A steel tube of φ40 mm × 6 mm t × 5.5 m L and YS400 MPa was used as a primary pipe, and a high-precision precision pipe was manufactured by press-processing in which the shaft diameter was set to 13% in the form shown in FIG. 10. In the early stage of manufacture, a die with an angle of 21 ° and a plug with an angle of 21 ° and a taper length of 11 mm were used. The plug was floated in the tube. Lubricating was applied to each elementary pipe before processing by immersing an elementary pipe in the lubricant in an application container. A fast-drying solvent dilution polymer lubricant was used as a lubricant.

During processing, the load in the pressing direction was always measured by the above measuring method, and the pressing was performed while comparing the measured load and the calculated load calculated in the above formula 4. In Equation 4 in this example, the values of a and n are optimal values derived by experiments in advance, where a = 0.00185 and n = 1 (corresponds to the case where the end state is rotational freedom). Was used.

During the processing of the plurality of pipes, the measured load exceeded the calculated load. Therefore, it was determined whether or not to continue the processing, and the processing was stopped, and the processing conditions were changed as follows. In other words, the dice were replaced with those having an angle of 11 degrees, and the plugs were replaced with those having an angle of 11 degrees and a taper length of 20 mm. After this exchange, processing was resumed, and the processing of the remaining plurality of pipes could be completed without difficulty.

Further, in the above-mentioned exchange and resumption of processing, the die inlet side and the die outlet side portion of the pipe in the process of entering the die for cutting are cut and separated, and the die inside of the pipe in which the plug for wire is inserted. After removing the die for the pre-use while the part is in place from the predetermined installation position, the die for the next use is installed in the same predetermined installation position, and the post-use plug is inserted into the pipe of the same size and the same YS for the next processing. Processing was resumed. In addition, the die | dye exit side part of the said separated pipe | tube could be employ | adopted as a product. The die inlet side of the same tube was scrap.

(Comparative Example 6.1)

With the same steel pipe as in Example 6.1, a high-precision precision pipe was manufactured by press working with the shaft diameter set to 13% in the form shown in FIG. In the beginning of manufacture, a die of an angle of 21 ° and a plug of an angle of 21 ° and a taper length of 20 mm were used. The plug was floated in the tube. Each elementary pipe before a process was apply | coated with the lubricant by immersing an elementary pipe in the lubricant in a coating container. The fast-drying solvent dilution polymer lubricant was used as a lubricant.

During processing, the load in the pressing direction was not measured, and the condition change in the abnormal situation was left to the judgment of the operator.

During the processing of the plurality of pipes, the dies were cracked, so the processing was stopped, the dies and the plugs were replaced with the same as the initial ones, and the lubricant in the lubricant coating container was totally replaced with a quick-drying solvent diluent polymer lubricant having a higher molecular weight. Then, since the processing was resumed later, the die was cracked again during the processing of the plurality of pipes from the start. Therefore, the processing was stopped, and the processing conditions were changed as follows. That is, the die was replaced with an angle of 11 degrees, and the plug was further replaced with an angle of 11 b degrees and a taper length of 20 mm. After this exchange, processing was resumed, and the processing of the remaining plurality of pipes could be completed without difficulty.

(Comparative Example 6.2)

The steel pipe of Example 6.1 was made into a primary pipe | tube, and the high dimension precision pipe by the drawing process which set the shaft diameter to 13% was manufactured. In the early stage of manufacture, a die with an angle of 21 ° and a plug with an angle of 21 ° and a taper length of 20 mm were used. The plug was floated in the tube. Bonding treatment and metal soap were applied to each elementary pipe before processing, and soldering to the pipe end necessary for drawing was carried out (this soldering process is unnecessary for pressing).

During processing, the load in the drawing direction was not measured, and the condition change in the abnormal situation was left to the judgment of the operator.

Since the dice cracked during the processing of the plurality of element pipes, the processing was stopped and the processing conditions were changed as follows. In other words, the dice were replaced with those having an angle of 11 degrees, and the plugs were replaced with those having an angle of 11 degrees and a taper length of 20 mm. After this exchange, processing was resumed, and the processing of the remaining plurality of pipes could be completed without difficulty.

For the examples and the comparative examples, the change conditions during machining, relative machining time, and loss during machining are shown in Table 6 along with the results of the dimensional accuracy of the product. The relative machining time was expressed by a value obtained by dividing the time (total machining time / total machining number) required for the machining of each example by that of Comparative Example 1. Dimensional precision was represented by thickness deviation and outer diameter deviation. These deviations were obtained from data obtained by analyzing the circumferential cross section of the tube, the thickness deviation as a value for the average thickness, and the outer diameter deviation as a value for a complete circle (target outer diameter).

As apparent from Table 6, the present invention was able to stably and efficiently manufacture a high dimension precision tube.

Example 7

Hereinafter, the present invention will be described in more detail with reference to Examples.

The device of Example 7.1 is a plug (1) having an inlet end diameter of 28 mm, a central diameter of 30 mm, and an outlet end diameter of 28 mm with a mirror surface facing the inner surface of the tube, and an inner fixed surface of the hole as a unitary fixed die. A tube press injector composed of a die 2 having a diameter of one hole and a hydraulic cylinder and a hydraulic cylinder, which can be operated in any of the operation modes of "continuous crimping" and "intermittent crimping". (3) was combined as shown in Fig. 1, and the plug 1 was a fixed plug in which one end was fixed and inserted into the tube, and the operation mode of the tube presser 3 was set to "intermittent crimping". Using this apparatus, carbon steel pipes having an outer diameter of 40 mm x thickness 6 mm were pressed to obtain a product tube having an outer diameter of 38 mm x thickness 6 mm.

In Example 7.2, except that the plug 1 was replaced with a fixed plug in Example 7.1 to form a floating plug, the carbon steel pipe having an outer diameter of 40 mm x thickness 6 mm was pressed and an outer diameter of 38 mm x thickness 6 A product tube of mm was obtained.

In Example 7.3, in Example 7.2, except that the setting of the operation mode of the tube indenter 3 was changed from "intermittent crimping" to "continuous crimping", pressurization of a carbon steel pipe having an outer diameter of 40 mm x thickness 6 mm was performed. Was carried out to obtain a product tube having an outer diameter of 38 mm and a thickness of 6 mm.

In Comparative Example 1, a plug 5 having an inlet end diameter of 28 mm, a central part diameter of 28 mm, and an outlet side end diameter of 26 mm having a mirror-faced surface in contact with the inner surface of the tube, and an inner fixed surface of the hole as an integral fixed die were made. A device in which a die 6 having a bore exit diameter of 38 mm and a hydraulic cylinder, which is operable by "intermittent pulling" and which exerts a pull force on the pipe in a set operation mode, are combined as shown in FIG. Configured. The plug 5 was a fixed plug that fixed one end and was inserted into the tube. Using this apparatus, the carbon steel pipe of 40 mm in diameter x 7 mm in thickness was pulled out, and the product pipe of 38 mm in thickness x 6 mm was obtained. In addition, in Comparative Example 1, the time required to pass through the die hole after closing the steel pipe tip was required.

In addition, in Comparative Example 2, in Example 7.1, the split die (not shown) was replaced with the plug (1), the same plug (5) as in Comparative Example 1, and the die (2) was assembled into the rotary forging machine (8). 9, the inner diameter of the outlet side thereof is the same as the diameter of the hole exit of the die 2), except that a device configuration as shown in Fig. 3 is used, and a press-fit of a carbon steel pipe having an outer diameter of 40 mm x thickness 5 mm is performed. It carried out and obtained the product pipe of external diameter 38mm x thickness 6mm.

Table 7 shows the results of measuring the dimensional accuracy of these product tubes. In addition, the measuring method of each deviation of the circumferential thickness, inner diameter, and outer diameter shown in Table 7 is as follows.

The outer diameter (or inner diameter) deviation was calculated as the maximum deviation with respect to a complete circle from the circumferential distribution data of the outer diameter (or inner diameter) measured by contacting the outer surface (or inner surface) of the micrometer with the tube and rotating the tube. The circumferential thickness deviation was measured directly as the maximum deviation with respect to the target thickness from the image of the thickness section. Further, the outer diameter deviation and the inner diameter deviation may be calculated from the circumferential distribution data of the distance between the tube and the laser oscillation source where the laser light is placed and measured, instead of contacting the micrometer. The circumferential thickness deviation may be calculated as a difference between the circumferential distribution data of the outer diameter and the circumferential distribution data of the inner diameter.

Moreover, thickness deviation (= circumferential thickness deviation), inner diameter deviation, and outer diameter deviation are defined as follows.

Thickness deviation = (maximum thickness-minimum thickness) / target thickness (or average thickness) × 100 (%)

Inner diameter deviation = (maximum inner diameter-smallest inner diameter) / target inner diameter (or average inner diameter) × 100 (%)

Outer diameter deviation = (maximum outer diameter-minimum outer diameter) / target outer diameter (or average outer diameter) × 100 (%)

According to Table 7, the product tube by the apparatus of Examples 7.1-7.3 is remarkably good in dimensional precision, especially when it is floated (Example 7.2), and the product tube of high dimension precision is obtained even if it carries out continuous compression. Number (Example 7.3). On the other hand, in the conventional drawing, the dimensional accuracy of the product pipe fell (Comparative Example 7.1). The dimensional accuracy of the product pipe also decreased in the press injection using a rotary forging machine (Comparative Example 7.2).

Example 8

Inventive Example 8.1

A plurality of dice (2, 20) according to the product dimensions of the respective pipes are made of steel pipes of φ40 mm x 6 mm t x 5.5 mm L, as shown in FIG. 20 are assembled, and then, the die 2 according to the product dimension of the preceding tube 4 is disposed in the pass line, and the die tube 2 is transferred to the die tube 2 by the indenter 2. After press-fitting into the die, the die swivel 19 is rotated to send a plurality of dice in order, and the dies 2 are replaced with the dies 20 according to the outer diameter of the product of the next pipe 7. In this case, the plug 22 is charged into the next pipe 5 before the die 20 is placed in the pass line, and then the next pipe 7 is diced by the indenter 2. It pressed in at (20) and performed the press processing. This was repeated to produce high precision precision tubes of various product dimensions.

(Inventive Example 8.2)

12 mm, a plurality of dice (2, according to the product dimensions of each pipe in the order of processing of the pipes in advance in the die straight stage 23, as shown in FIG. 12). 20, ..., 20 are assembled, and then, the die 2 according to the product dimension of the preceding tube 4 is disposed in the pass line, and the die tube 2 is transferred to the die tube 2 by the indenter 2. After pressing the die and finish the pressing process, the die straightener 23 is sent straight to send a plurality of dice in order, and the dies 2 are replaced with dies 20 according to the outer diameter of the product of the next pipe 7. Was placed in the pass line. At this time, the plug 22 was inserted into the next pipe | tube 5 before the dice | dies 20 were arrange | positioned in a pass line. Subsequently, the next pipe 7 was press-fitted into the die 20 by the indenter 2, and the pressing process was performed. This was repeated to produce high precision precision tubes of various product dimensions.

(Comparative Example 8.1)

Using a steel pipe having a diameter of 40 mm x 6 mm t x 5.5 mL as a raw material, a plurality of dies of different hole shapes were prepared and pressed as shown in FIG. The die 2 used initially is arrange | positioned in a pass line, First, the former pipe 4 was press-fitted into the die 2 by the indenter 3, and the press processing was complete | finished. Next, by hand, the die 20 was replaced with the die 2 and the die 20 according to the outer diameter of the product of the next pipe 7 was disposed in the pass line. At this time, the plug 22 was inserted into the next pipe | tube 7 in a pass line before the dice | dies 20 were arrange | positioned in a pass line. Subsequently, the next pipe 7 was press-fitted into the die 20 by the indenter 2, and press-molding was performed. By repeating this, high-precision precision tubes of various product dimensions were manufactured.

(Comparative Example 8.2)

Using a steel pipe of φ40mm × 6mm t × 5.5m L as a raw material, a plurality of dies of different hole shapes were prepared, and pressed as shown in FIG. 13. The dice | dies 2 used initially are arrange | positioned in a pass line, First, the former pipe | tube 4 was press-fitted into the dice | dies 2 by the indenter 2, and the press processing was complete | finished. Next, by hand, the dice | dies 20 corresponding to the outer diameter of the product of the next pipe | tube 7 were changed into the dice | dies 7, and were arrange | positioned in a pass line. At this time, the next pipe 7 was once moved out of the pass line to charge the plug 22, and then returned to the pass line. Subsequently, the next pipe 7 was press-fitted into the die 20 by the indenter 2, and press-molding was performed. This was repeated to produce high precision precision tubes of various product dimensions.

Table 8 shows the processing efficiency and the dimensional accuracy of the product in Examples and Comparative Examples. The processing efficiency was evaluated by the number of presses of the steel pipe per unit working time, and Table 8 shows the processing efficiency of Comparative Example 2 as one and the relative value thereof. Dimensional precision was represented by thickness deviation and outer diameter deviation. These deviations were obtained from data obtained by analyzing the circumferential cross section of the tube, the thickness deviation as a value for the average thickness, and the outer diameter deviation as a value for a complete circle (target outer diameter).

As is apparent from Table 8, the present invention significantly improved the press working efficiency.

Example 9

Hereinafter, the present invention will be described in more detail with reference to Examples.

Example 9.1

As shown in FIG. 14, the pipe bending fine adjustment means 24 was provided in the immediate vicinity of the exit side of the die | dye 2. As shown in FIG. Moreover, although illustration is abbreviate | omitted, the continuous indenter of the system which inserted the pipe | tube 4 in endless orbit continuously and continuously press-fits into the die | dye 2 was provided in the inlet side of the dice | dies 2.

As shown in Fig. 15, the pipe bending fine adjustment means 24 has a hole shape 26 having a hole 27 through which the pipe passes, in a plane perpendicular to the clearance direction with the support substrate 28. A direction (orthogonal to any one or two or more places out of four places of the outer circumference of the hole type 26 by the hole type moving mechanism 29 supported by the same support substrate 28 so as to be movable) (perforated) The pressing force in the moving direction 33 is used. As shown in Fig. 16, the wedge-shaped mold 30 having the tapered surface in contact with the outer circumferential portion of the hole 26 is screwed thereto. It was made to move by moving in the clearance direction 25 with the adjustment screw 31. In FIG. 16, when the adjusting screw 31 is rotated to the right, the wedge-shaped die 30 is raised, and the hole 26 in contact with the tapered surface moves to the left. Further, after fine adjustment of the hole position, the fixing die 32 is tightened to fix the hole die 26 to the support substrate 28.

By using this device, a φ40mm × 6mm t × 5.5m L steel pipe is used as a material, and this material is continuously pushed into the die 2 while the plug 1 fmf is inserted and floated therein. The manufacture of high precision precision pipes was carried out. The steel pipe after the pressing process penetrated the hole 27 of the hole type 26 immediately near the exit side of the die 2. The hole 27 of the hole type 26 was a straight hole, and the hole diameter was 0.5 mm larger than the exit hole diameter (φ35 mm in this example) of the die 2.

In practice, a plurality of dummy tubes are used before manufacturing, and a bending test is performed by changing the hole position by several points. The bending of the tube is measured, and the relationship between the amount of change in the hole position and the amount of change in the bend of the tube after compression is obtained. It was. In practice, during the manufacturing trials, when the bending of the tube exceeded a predetermined threshold, fine adjustment of the hole positioning was performed by moving the hole in the direction in which the bending becomes smaller based on the above relationship.

(Example 9.2)

As shown in FIG. 17, the pipe bending fine adjustment means 24 is provided in the immediate vicinity of the exit side of the die 2, and the guide cylinder 35 is provided in the immediate vicinity of the inlet side of the die 2, The guide cylinder 36 was provided in the immediate vicinity of the exit side of the bending fine adjustment means 24. Moreover, although not shown, the tube 4 was inserted into the endless track of the inlet side of the inlet guide cylinder 35 continuously. The continuous indenter of the system which press-fits into the dice | dies 2 was installed.

As shown in Fig. 18, the pipe bending fine adjustment means 24 has a hole shape 26 having a hole 27 through which the pipe passes, in a plane perpendicular to the clearance direction with the support substrate 28. A direction (orthogonal to any one or two or more places out of four places of the outer circumference of the hole type 26 by the hole type moving mechanism 29 supported by the same support substrate 28 so as to be movable) (perforated) Pressing or drawing in the moving direction 33, the compression or drawing force is applied by a small hydraulic cylinder 34 in contact with the outer peripheral portion of the hole type 26. In FIG. 18, the hole type 26 moves in the opposite direction of the two hydraulic cylinders 34 by subtracting the pressure difference between the two hydraulic cylinders 34 that face each other. Furthermore, after fine adjustment of the hole position, the hole type 26 is fixed to the support substrate 28 with the pressure difference between the opposing hydraulic cylinders 34 being zero.

Using this apparatus, a φ40mm × 6mm t × 5.5n L steel pipe is used as a material, and this material is continuously pressed while the plug 1 is inserted into the pipe and floated, and pressed into the die 2. The manufacture of high precision precision pipes was carried out. The steel pipe before the pressing process passes through the inlet guide cylinder 35, and the steel pipe after the pressing process passes through the hole 27 and the outlet guide cylinder 36 of the hole type 26 immediately near the exit side of the die 2. Penetrated sequentially. The hole 27 of the hole type 26 is a tapered hole, and the hole diameter of the maximum inner diameter part (located at the inlet side) is 2.5 mm compared to the exit hole diameter of the die 2 (φ 33 mm in this example). Taken large. In addition, the hole diameter of the minimum inner diameter part (located at the exit side) of the hole shape 26 was made the same as the exit hole diameter of the die | dye 2. In addition, the guide cylinders 35 and 36 of the inlet side and the outlet side were made into the cylinder of the inner diameter which is 0.5 mm larger than the outer diameter of the same tube so that a defect may not enter a tube.

Actually, a plurality of dummy pipes were used before the production trial, and a bending test was performed in which the hole positions were changed by several points, and the bending of the pipes was measured, and the relationship between the amount of change in the hole positions and the amount of change in bending of the pipe after the pressing was obtained. In fact, during the manufacturing trials, when the bending of the tube exceeded a predetermined threshold value, fine adjustment of the pore position was performed by moving the hole in the direction in which the bending becomes smaller based on the above relationship.

Comparative Example 9.1

As shown in FIG. 19, the guide cylinder 35 was provided in the immediate vicinity of the inlet side of the dice | dies 2, and the guide cylinder 36 was provided in the vicinity of the same exit side. Moreover, although illustration is abbreviate | omitted, the continuous indenter of the system which inserted the pipe | tube 4 in the endless track and continuously press-in the die | dye 2 was installed in the inlet side of the inlet side guide cylinder 35.

Using this device, a steel pipe of φ40 mm x 6 mm t x 5.5 mL is used as the material, and the material is continuously transferred while the plug 1 is inserted into the tube and floated, thereby cutting the die 2 (in this example, the exit hole diameter). A high-precision precision tube was manufactured by press-fitting into φ 33 mm). The steel pipe before the pressing process passed through the inlet side guide cylinder 35, and the steel pipe after the pressing process passed through the outlet side guide cylinder 36.

(Comparative Example 9.2)

As shown in FIG. 20, nothing was provided in the immediate vicinity of the inlet side of the dice | dies 2, and the immediate vicinity of the outlet side. In addition, although illustration is abbreviate | omitted, the continuous indenter of the system which inserted the pipe | tube 4 in the endless track and continuously press-fits into the dice | dies 2 at the inlet side of the dice | dies 2 was installed.

Using this device, a steel pipe of φ40 mm x 6 mm t x 5.5 mm L is used as the material, and the material is continuously conveyed while the plug 1 is inserted into the pipe and floated, and the dies 2 (in this example, the exit hole diameter) are used. The high-precision precision pipe by press-fitting into φ35 mm) was manufactured.

(Comparative Example 9.3)

As shown in FIG. 21, nothing was provided in the immediate vicinity of the inlet side of the dice | dies 2, and the immediate vicinity of the outlet side.

The injector 37 was provided in the die | dye 2 exit side, without providing an indenter in the die | dye 2 inlet side.

Using this device, a steel pipe of φ40mm × 6mm t × 5.5m L is used as the material, and the material is held by inserting the plug 1 into the pipe, and the pipe end is gripped with a drawer 37 to form the steel pipe. The drawing was carried out from the die 2 (in this example, the exit hole diameter φ 35 mm) in the drawing direction 38 to produce a high-precision precision tube by drawing.

Table 9 shows the results of investigating the bending and dimensional accuracy of the tubes produced by the methods of the above Examples and Comparative Examples. The bending of the tube was evaluated by arranging a linear ruler in the tube, and evaluating the maximum value of the gap between the straight tube and the tube at the center of the tube per 500 mm of tube length. The dimensional accuracy of the tube was expressed by thickness deviation and outer diameter deviation (maximum value of data of a plurality of manufactured tubes in each example). These deviations were obtained from data obtained by analyzing the circumferential cross section of the tube, the thickness deviation as a value for the average thickness, and the outer diameter deviation as a value for a complete circle (target outer diameter).

As apparent from Table 9, the present invention was able to sufficiently prevent bending of the tube after the compression while obtaining remarkably good dimensional accuracy.

Example 10

As an embodiment of the present invention, the facility heat as shown in Fig. 22 was constructed. '39' is a pressurizing apparatus, which inserts and floats the plug 1 into the tube, and press-fits the tube continuously by pressing the die 1 into the die 2 with the presser apparatus 43. will be.

As the preferred embodiment, the press processing device 39 is provided with a die exchange device 45, a plug exchange device 44, and a bending prevention device 46 configured as described above.

On the inlet side of the press processing device 39, a pipe end surface grinding device 40, a lubricant dipping agent container 41, and a drying device 42 are disposed sequentially from the upstream side. The tube end surface grinding apparatus 40 is comprised so that it can grind perpendicularly which cuts the cross section of the pipe which lined up on the base by the grinding bite at right angles to a tube axis direction. The lubricant dipping container 41 stores a dry liquid lubricant emulsion, and the lubricant is applied to the tube by immersing the tube in the emulsion bath. The drying apparatus 42 is comprised so that drying is possible by blowing a tube with the hot air blown after the application | coating of the lubricating agent side by side. Furthermore, at the inlet side of this facility row, a pipe receiving base 47 is installed to receive the pipes conveyed from the whole process and pass them to the pipe cross-section grinding device 40. Also, the outlet side is press-processed to find a pipe made of product pipe in a later step. A pipe finder 48 was installed.

Using this equipment heat, the pipe section is perpendicular to the cross section of the tube with an oxidized scale, having various dimensions in the dimensional range of 25 to 120 mm φ, thickness 2 to 8 mm, and length 5 to 13 m. Drying and pressing were performed sequentially to obtain a product tube.

On the other hand, in FIG. 23, as a comparative example, the manufacturing equipment heat | fever by conventional drawing is shown. This equipment heat is provided by the pipe receiving stand 47 on the inlet side of the drawing processing apparatus 50 and the pipe searching stand 48 on the outlet side, and the drawing processing apparatus 50 connects the plug 1 to the pipe. The tube is drawn out from the die 2 by the drawing processing device 50 while charging and floating. Further, the drawing processing device 50 was provided with a plug exchange device 44 and a die exchange device 45 configured in the same manner as in the embodiment. In this facility heat, it is not possible to pull out the scaled element pipe like Example, and it is necessary to make an element pipe the tube which passed the 1st pretreatment process shown in FIG. 23 and the 2nd pretreatment process following this.

The first pretreatment process is essential as a means of forming a firm lubricating film for drawing, short cuts of scaled pipes ⇒ descaling by pickling ⇒ neutralizing acids with alkali ⇒ water washing ⇒ bonding ⇒ metal soap It consists of many sequential steps called application ⇒ drying. The plurality of immersion containers or apparatuses for the first pretreatment step are arranged in separate lines because the productivity decreases when placed in the same line as the drawing processing device 50. In addition, the second pretreatment step is essential as a means for soldering the end of the pipe using, for example, a rotary forging machine in order to hold the drawing processing device 50. If it arrange | positions in the same line, since productivity will fall, it is arrange | positioned in a separate line.

Using the facility heat of this comparative example, the pre-treated tube which processed the scaled element pipe same as an Example sequentially by the 1st, 2nd pretreatment process was pulled out, and the product tube was obtained.

Table 10 shows the production time required for the examples and the comparative examples, and the dimensional accuracy of the product tubes. The time required for production was evaluated by the total processing time / total number of treatments until the product tube was obtained from a scaled tube of a predetermined number of lots, and in Table 10, the evaluation value of the comparative example was 1, and is represented by a relative ratio with it. Dimensional precision was represented by thickness deviation and outer diameter deviation. These deviations were obtained from data obtained by analyzing the circumferential cross section of the tube, the thickness deviation as a value for the average thickness, and the outer diameter deviation as a value for a complete circle (target outer diameter).

As is apparent from Table 10, the present invention was able to efficiently manufacture high dimension precision tubes.

The high-precision precision tube of the present invention has a remarkably good dimensional accuracy and, as a result, has a good fatigue strength, and can be manufactured at a low cost, and thus has an excellent effect of greatly contributing to the promotion of weight reduction of automobile drive system components and the like. Exert. Moreover, according to the manufacturing method of this invention, the outstanding effect that it is possible to manufacture the metal pipe with remarkably good dimensional precision over a wide range of pipe | tube requirements is at low cost.

Claims (62)

Any one or two or more of an outer diameter deviation, an inner diameter deviation, and a circumferential thickness deviation manufactured by performing a press to press and pass a metal tube through a die of the die while the plug is inserted into the tube is 3.0 It is less than%, high precision precision tube as it is pressed. The method of claim 1, An outer diameter deviation, an inner diameter deviation, and a circumference manufactured by pressurizing the metal tube by inserting it into the hole of the die by inserting the plug into the tube and making the thickness of the metal tube on the outlet side of the die less than that of the inlet side. Any one or two or more of the direction deviations in a direction is 3.0% or less, The high dimension precision pipe as it is pressed. The method according to claim 1 or 2, And the pressurizing is performed while the metal tube is inscribed with the entire circumference of the plug and the entire circumference of the die within the same cross section of the tube. The method according to any one of claims 1 to 3, High dimension precision tube, characterized in that the die is an integral and / or fixed die. A method for producing a high precision precision pipe, comprising: performing a press to push a metal pipe into a hole of a die while a plug is inserted in the pipe. The method of claim 5, The thickness of the pipe | tube on the exit side of the dice | dies shall be below the thickness of the pipe | tube of the inlet side of dice | dies, The manufacturing method of the high precision precision pipe | tube of (5) characterized by the above-mentioned. The method according to claim 5 or 6, And the pressurizing is performed while the metal tube is circumscribed the entire circumference of the plug and the circumference of the circumference of the die within the same cross section of the tube. The method according to any one of claims 5 to 7, And said die is an integral and / or fixed die. The method according to any one of claims 5 to 8, And the plug is a floating plug. The die according to claim 5, wherein any one or two or more of the outer diameter deviation, the inner diameter deviation, and the circumferential thickness deviation of the tube are improved by pressing to form a high-precision precision tube, or the plug is inserted and floated in the tube. A high efficiency manufacturing method of high dimension precision pipe, characterized in that the pipe is continuously transferred into the die by the pipe transfer means on the inlet side. The method of claim 10, And said pipe conveying means is a caterpillar for holding a tube before processing. The method of claim 10, And said pipe conveying means is an endless belt for crimping the tube before processing. The method of claim 10, And said pipe conveying means is a mechanism for grasping a tube before processing and transferring it intermittently alternately. The method of claim 10, And said pipe conveying means is a press for sequentially pressing the tube before processing. The method of claim 10, The said pipe conveying means is a hole-shaped roll which pinches the tube before a process, The high efficiency precision manufacturing method of the high precision precision pipe characterized by the above-mentioned. The method of claim 15, And said hole roll is a hole roll of two or more rolls. The method according to claim 15 or 16, A high-efficiency precision pipe manufacturing method, characterized in that the two or more stand-shaped rolls are installed. The method of manufacturing a high-precision precision tube with good surface quality according to claim 5, wherein after forming a lubricating film on the inner and / or outer surface of the tube, a plug is inserted into the tube and the tube is pressed by a die. . The method of claim 18, The pipe for forming the lubricating film is a steel pipe with an oxide scale (Scale) attached, characterized in that the high-quality precision tube with a good surface quality. The method of claim 18 or 19, A method for producing a high-precision precision tube with good surface quality, wherein the lubricant film is formed using a liquid lubricant. The method of claim 18 or 19, A method for producing a high-precision precision tube with good surface quality, wherein the lubricating film is formed using a grease-based lubricant. The method of claim 18 or 19, A method for producing a high-precision precision tube with good surface quality, wherein the lubricating film is formed by using a dry resin. The method of claim 22, The dry resin, or a liquid obtained by diluting the dry resin with a solvent, or an emulsion of the dry resin is applied to a tube, followed by warm air, or by air drying to form the lubricating film. The manufacturing method of the high precision precision pipe of which surface quality is good. The method of manufacturing a high-precision precision tube according to claim 5, wherein a high-precision precision tube is manufactured from the same size of the primary pipe having a different degree of workability with high precision. Iv) A method for producing a high precision precision pipe, characterized in that a plug is inserted into the pipe as much as possible, and the pipe is pressed with a die. The method of claim 24, The plug is floated in the tube, and the tube is continuously fed to a die. The method of claim 24 or 25, And said plug is a plug of which the tapered angle of the expansion pipe portion is less than the tapered angle of the shaft diameter portion. The method according to any one of claims 24 to 26, wherein A target outer diameter of the tube on the outlet side of the die is less than the outer diameter of the tube on the inlet side. The method of manufacturing a high-precision precision pipe by press-processing by injecting a tube having a plug inserted therein into a hole of a die, wherein the surface of the shaft diameter portion as the plug is formed at an angle of 5 degrees. A cocoon characterized by using a plug having a diameter of -40 ° and a length of the shaft diameter portion of 5 to 100 mm, and a die having an angle of 5 to 40 ° at which the inner surface of the hole on the inlet side forms the center axis as the die. Stable manufacturing method of water precision pipe. The method of claim 28, The length of the bearing part of the said plug was 5-200 mm, The stable manufacturing method of the high precision precision pipe characterized by the above-mentioned. The method of claim 28 or 29, The thickness of the pipe | tube on the exit side of the said dice | dies is set to below the thickness of the pipe | tube on the inlet side, The stable manufacturing method of the high precision precision pipe | tube characterized by the above-mentioned. The method according to any one of claims 28 to 30, An integrated fixed die is used as said dice, The stable manufacturing method of the high precision precision pipe characterized by the above-mentioned. The method of any one of claims 28 to 31, A method for stably manufacturing a high precision precision pipe, wherein the plug is floated in the pipe. The method of manufacturing a high-precision precision tube according to claim 5, wherein the plug is inserted into a tube and floated, and the tube is press-fitted into a die and pressed to measure the load in the press-processing direction during the press-processing. And comparing the measured load with the calculated load calculated from any one of the following [Formula 1] to [Formula 3] from the material characteristics of the element pipe, which is a pipe before processing, and determining whether to continue the pressing process based on the result. Stable manufacturing method of high precision precision tube characterized by the above-mentioned. [Equation 1] σ _k × elementary pipe cross-sectional area Where σ _k = YS x (1-a x λ), λ = (L / √n) / k, a = 0.00185 to 0.015, L: tube length, k: cross-section secondary radius, k ² = (d ₁ ² + d ₂ ² ) / 16, n: tube end state (n = 0.25 to 4), d ₁ : outer diameter of tube, d ₂ : inner diameter of tube, YS: yield strength of tube Yield strength YS × tube cross-sectional area of tube Equation 3 Tensile strength TS of element pipe The method of claim 33, wherein If the measured load is less than or equal to the calculated load, it is determined that the process is to be continued and processing continues as it is. On the other hand, if the measured load is greater than the calculated load, it is determined that it cannot be continued. The process for stably manufacturing high-precision precision tubes, wherein processing is resumed after exchanging the one with a different shape corresponding to the same product size. The method of claim 34, wherein A die and / or a plug to be used after the replacement is characterized in that the angle of the die and the plug is smaller than that before the replacement. 36. The method of any one of claims 33 to 35, A lubricant is applied to the element pipe prior to the pressing operation, and the type of the lubricant is changed only when the measured load exceeds the calculated load. The tube having a plug that can contact the entire inner circumference of the metal tube, a die having a hole that can contact the entire circumference of the outer surface of the tube, and a tube press for crimping the tube, wherein the tube is inserted into the tube with the plug inserted therein. An apparatus for manufacturing a high-precision precision pipe, comprising: a press which is press-fitted into a hole of the die by a press into a die. The method of claim 37, And said die is an integral and / or fixed die. The method of claim 37 or 38, And the plug is a floating plug. The method according to any one of claims 37 to 39, Apparatus for producing a high precision precision pipe, characterized in that the pipe compactor continuously presses the pipe. The method according to any one of claims 37 to 39, And the tube press presses the tube intermittently. 38. The method of manufacturing a high precision precision tube according to claim 37, wherein the plug is inserted into a tube and floated, and the tube is pressed continuously and intermittently into the die to pass the die. A high efficiency manufacturing method of a high precision precision pipe, arranged on a circumference, and moving any one of these dice in the circumferential direction arranged according to the product dimension, and placing the die in a pass line for use in compression. 38. The method of manufacturing a high precision precision tube according to claim 37, wherein the plug is inserted into a tube and floated, and the tube is pressed continuously and intermittently into the die to pass the die. A high efficiency manufacturing method of a high precision precision pipe, arranged in a straight line, and moving any one of these dice in a straight line arranged in accordance with the product dimensions, and placing the die in a pass line for use in compression. The method of claim 42 or 43, wherein In changing the product dimensions between the previous pipe and the next pipe, after the end of the compression of the previous pipe, the next pipe is stopped at the die inlet side, before or after the movement of the die according to the product size of the next pipe, A high efficiency manufacturing method of a high precision precision tube, wherein the plug according to the same product dimension is inserted into the following tube. 38. The die according to claim 37, wherein the die which passes the tube, the indenter which presses the tube into the die in the pass line, and a plurality of dice are supported in the form of an array arranged on the same circumference and conveyed in the circumferential direction of any one die. A high efficiency manufacturing apparatus for high precision precision pipes with a die swivel disposed in a pass line. 38. The die according to claim 37, wherein the die which passes the tube, the indenter which presses the tube into the die in the pass line, and a plurality of dice are supported in a form arranged on the same straight line and conveyed in the straight line direction so that any one die is transferred. High-efficiency manufacturing apparatus for high precision precision pipes having a die straight stage disposed in a pass line. The method of manufacturing a high precision precision pipe according to claim 5, wherein the plug is inserted into the pipe and floated, and the pipe is pressed into the die and passed through. The manufacturing method of the high precision precision pipe is provided immediately near the die outlet side. A method for producing a high precision precision pipe, characterized by preventing the bending of the pipe by passing the pipe on the die exit side through a hole in which the in-plane position orthogonal to the direction is adjusted in advance. The method of claim 47, A method of manufacturing a high precision precision pipe, wherein the pipe at the die inlet side and / or the hole outlet side is passed through a guide tube. 49. The method of claim 47 or 48, A method for producing a high precision precision pipe, characterized in that the pipe is continuously pressed into a die. 38. The apparatus for manufacturing a high-precision precision tube having a die for passing the tube and a press-fitting machine for pressing the tube into the die, wherein the hole type passes the tube immediately in the vicinity of the die outlet; And a support substrate for movably supporting the hole mold in a plane orthogonal to the clearance direction, and a tube bending fine adjustment means having a support mechanism for moving the hole mold supported by the support substrate. Manufacturing equipment of high dimension precision pipe. 51. The method of claim 50, The hole-type moving mechanism is of a type in which one or two or more portions of the hole-shaped outer circumference are press-fitted in a direction orthogonal to the clearance direction through a tapered surface of a wedge-shape mold moving in the clearance direction. Manufacturing apparatus of high dimension precision pipe, characterized in that The method of claim 51, Apparatus for producing a high precision precision pipe, characterized in that for pushing the movement of the wedge-shaped mold with a screw. 51. The method of claim 50, The hole-type moving mechanism is a device of manufacturing high-precision precision pipe, characterized in that the one or two or more of the hole-shaped outer peripheral portion is of a type that is pushed or drawn out in a direction orthogonal to the clearance direction. The method of claim 53, Apparatus for producing a high precision precision pipe, characterized in that for pushing or drawing the press-in or pull-out of the press-in or pull-out method to the fluid pressure cylinder. The method of any one of claims 50-54, The hole diameter of the said hole type is more than the exit hole diameter of the said dice | dies, The manufacturing apparatus of the high precision precision pipe | tube characterized by the above-mentioned. The method of any one of claims 50-55, And the hole-shaped hole is a straight hole or a tapered hole. The method of any one of claims 50-56, Furthermore, the apparatus of manufacturing a high precision precision pipe, having a guide tube for passing the pipe on the die inlet side and / or on the pipe bend fine adjustment means outlet side. The method of any one of claims 50-57, And said indenter is a continuous indenter capable of continuously indenting the tube. A pipe section grinding device for manufacturing a high-precision precision pipe having a press-fitting press according to claim 37, wherein the pipe section grinding device grinds the cross section of the pipe at a right angle in the tube axial direction, and a lubricant dipping container for immersing and applying lubricant to the pipe. And a drying apparatus for drying the tube coated with lubricant, and the press-fitting plant values arranged in this order. The method of claim 59, Further, a row of equipment for manufacturing high precision precision pipes, wherein a cutting device for cutting a tube into short lengths is disposed at an inlet side of the pipe cross-section grinding device. 61. The method of claim 59 or 60, Instead of the lubricant immersion coating container and the drying device, a lubricant spray coating device for spraying and applying a lubricant to a tube on the die inlet side of the press processing device, or a lubricant spray coating drying for spraying and spraying a lubricant onto the tube A row of manufacturing equipment for high dimension precision pipes, wherein the device is disposed. 63. The method of any of claims 59-61, One or two of a die exchanger for replacing the die, a plug exchanger for replacing the plug, and a bending prevention device for preventing bending of the pipe on the die outlet side in parallel with the press-processing device. Row of manufacturing facilities of the high precision precision pipe which arrange | positioned the above.