JP2005144501A - Manufacturing equipment train of tube of high dimensional accuracy - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing equipment train of a tube of high dimensional accuracy capable of efficiently manufacturing the tube of high dimensional accuracy by extrusion. <P>SOLUTION: The manufacturing equipment train of a tube of high dimensional accuracy has an extrusion device 1 in which a plug 6 is fitted in the tube, and the tube is pressed into and extruded through a die 7 in a floating manner, and a tube end face grinding device 2 to grind an end face of the tube at a right angle to the axial direction of the tube, a lubricant immersion and application tank 3 in which the tube is immersed in lubricant and the lubricant is applied to the tube, a drying device 4 to dry the tube with the lubricant applied thereto, and the extrusion device 1 are arranged in this order. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manufacturing equipment line for high dimensional accuracy pipes, and more particularly, to a manufacturing equipment line for high dimensional precision pipes that can efficiently manufacture pipes that require high dimensional accuracy such as automobile drive system parts. .

  Usually, metal pipes such as steel pipes (hereinafter also simply referred to as pipes) are roughly classified into welded pipes and seamless pipes. Welded pipes are manufactured by rounding the width of the strip and welding by welding both ends of the rounded width, such as ERW steel pipes, while seamless pipes are used to drill a mass of material at high temperatures. It is manufactured by a method of rolling with a mandrel mill afterwards. In the case of a welded pipe, the bulge of the welded portion is ground after welding to improve the dimensional accuracy of the pipe, but the thickness deviation exceeds 3%. In the case of a seamless pipe, it is easy to be eccentric in the drilling process, and the thickness deviation is reduced in the subsequent process. However, the thickness deviation in the product stage is usually 8% or more.

  Recently, due to environmental problems, the weight reduction of automobiles has been spurred, and drive system components are being replaced from solid rods to hollow tubes. These drive system parts and the like are required to have a high dimensional accuracy of 3% or less, more strictly 1% or less, with a deviation of one or more of the thickness, inner diameter, and outer diameter.

Therefore, conventionally, both a welded pipe and a seamless pipe have been attempted to be made into a high dimensional accuracy pipe by pulling out the pipe cold using a die and a plug (for example, see Patent Document 1).
Japanese Patent No. 2812151

  However, with the drawing tool, the die and the pipe in the machining bite are used in cases where the drawing force is not sufficient and the diameter reduction rate must be lowered due to restrictions on the equipment and the large thickness and diameter of the pipe. As a result of insufficient contact between the extraction plug and the tube, smoothing of the inner and outer surfaces of the tube, and unevenness remaining, the dimensional accuracy of the tube tends to be lowered. There has been a need for a production method that can produce tubes. In addition, since it is necessary to apply tension while strongly pulling the tip of the tube in the drawing, it is necessary to squeeze the tip of the tube and pull out the tube in a single shot, and the processing efficiency is extremely low.

  In order to solve the above-mentioned problems, the present inventors have studied a processing method capable of producing pipes with higher dimensional accuracy than drawing, and have concluded that punching is a promising candidate. In the case of punching, the plug is inserted into the pipe, and the pipe is pushed into the die while the plug is floating, so that compressive stress acts in the machining tool. As a result, the tube can sufficiently contact the plug and the die regardless of the entry side or exit side of the machining tool. In addition, even in the case of a small diameter reduction ratio, the inside of the machining tool is in a compressive stress state, so that the tube and the plug, the tube and the die are more easily contacted than the drawing, and the tube is easily smoothed and increased. A tube with dimensional accuracy is obtained.

  However, in order to efficiently process a long blank tube of 5 m or more into a tube with a target dimensional accuracy when performing punching, not only the processing equipment but also the entire equipment row is optimized. There is a need.

  On the other hand, in the conventional drawing, in order to improve the dimensional accuracy of the pipe, it is necessary to bond the pipe before the drawing and then apply metal soap to form a sufficient lubricating film. Therefore, it is necessary to take a sufficient time for forming the lubricating film, and further, pretreatment of the pipe such as pickling is necessary, and in the drawing equipment row, a plurality of tanks for pretreatment such as pickling and a lubricating treatment are used. Multiple tanks were required. In addition, in order to perform the drawing process, it has been necessary to perform a piercing process on the tip of the pipe with a rotary forging machine or the like. However, if these equipment lines are brought online and arranged on the entry side of the drawing processing apparatus, productivity will be reduced and a major problem will occur. Therefore, lubrication is performed in a separate process and the pipe is turned into an on-line equipment line. It was thrown in and processed.

  In other words, the conventional high-precision pipe manufacturing equipment line is premised on a drawing process that requires a long pretreatment process, and thus it has been difficult to increase the manufacturing efficiency.

  Then, an object of this invention is to provide the manufacturing equipment row | line of the high dimensional accuracy pipe | tube which can manufacture a high dimensional accuracy pipe | tube efficiently by a punching process.

  In addition, the high dimensional accuracy pipe | tube said to this invention is a pipe | tube in which any one or two or more of an outside diameter deviation, an inside diameter deviation, and a thickness deviation (: circumferential direction thickness deviation) is 3% or less. Each deviation is derived by the following equation.

  Deviation = (variation range (= maximum value−minimum value)) / (target value or average value) × 100%

  The present invention that has achieved the above object is as follows.

  (1) A manufacturing equipment row of high dimensional accuracy pipes having a punching device that inserts a plug into a pipe and floats it, and pushes the pipe into a die and passes it through, and the end face of the pipe is ground perpendicular to the pipe axis direction. A pipe end surface grinding device, a lubricant dip coating tank for dip coating a lubricant on the tube, a drying device for drying the pipe coated with the lubricant, and the punching processing device are arranged in this order. Manufacturing equipment line of high dimensional accuracy pipes.

  (2) Furthermore, the cutting equipment which cut | disconnects a pipe | tube in short length has been arrange | positioned at the entrance side of the said pipe end surface grinding apparatus, The manufacturing equipment row | line of the high dimensional accuracy pipe | tube as described in (1) characterized by the above-mentioned.

  (3) Instead of the lubricant dip coating tank and the drying device, a lubricant spray coating device that sprays and applies a lubricant to the pipe on the die entrance side of the punching processing device, or sprays and applies the lubricant to the tube A manufacturing equipment row of high dimensional accuracy pipes according to (1) or (2), wherein a lubricant spray coating and drying device for drying is disposed.

  (4) One of a die changing device for exchanging the die, a plug changing device for exchanging the plug, and a bending preventing device for preventing the bending of the pipe on the die exit side, in addition to the punching device. Two or more are arranged, The manufacturing equipment row | line | column of the high dimensional accuracy pipe | tube in any one of (1)-(3) characterized by the above-mentioned.

  According to the present invention, a high dimensional accuracy tube can be efficiently manufactured.

  In the case of conventional drawing, a sufficient lubricating film is necessary to obtain a high dimensional accuracy, and therefore, a bonding process with good lubrication has been performed. In this method, the tube is previously pickled to remove the oxidized scale, and further, alkali washed to neutralize the acid, and then washed with water. Thereafter, the tube was immersed in a tank for performing a bonde treatment to form a lubricating film, and subsequently immersed in a metal soap tank to form a film, and then the tube was dried with hot air. For this reason, these processes take several hours or more, and if these processes are taken into the equipment line where the pipes are pulled out, the productivity is remarkably hindered.

  Compared to this, according to the punching process, it is easy to obtain a high dimensional accuracy even if the diameter reduction ratio is small, and therefore, the lubrication of the pipe is simple. That is, it is not necessary to pickle the tube, and it is only necessary to dry it with hot air after dip coating the lubricant. However, the squareness of the end face of the pipe is important for continuously performing the punching, and a grinding device for producing this squareness is necessary.

  These processes prior to the punching process are most efficiently performed in the order of squareness of the tube end face → lubricant dip coating → drying. In view of these points, in the present invention, a pipe end surface grinding apparatus that grinds an end face of a pipe at right angles to the pipe axis direction, a lubricant dip coating tank for dip coating a lubricant on the pipe, and a pipe coated with the lubricant are provided. Since the drying apparatus to be dried is an equipment row arranged in this order on the entry side of the punching apparatus, a high dimensional accuracy tube can be efficiently manufactured.

  In addition, since it is more efficient to set the squareness of the pipe end face immediately after cutting the pipe into a short length, the equipment row of the present invention has a short pipe length on the inlet side of the pipe end face grinding apparatus. What arrange | positioned the cutting device which cut | disconnects is preferable.

  In addition, if a lubricant that is easy to form a film by drying is applied as a lubricant, spraying (spraying) directly on the die entry side in the punching device instead of dip-coating on the entry side of the punching device and then drying. It may be applied and then dried, or if the lubricity is better, drying may be omitted and the tube may be punched in a wet state. Therefore, the equipment row of the present invention includes a lubricant spray coating device or a tube for spraying a lubricant on a pipe on the die entrance side of the punching device, instead of the lubricant dip coating tank and the drying device. Alternatively, a lubricant spray coating / drying apparatus for drying after spraying the lubricant may be disposed.

  In order to further improve the efficiency of the punching process, it is preferable that the die and the plug can be easily exchanged online, and that the tube is not bent on the die exit side. From these points, in the equipment row of the present invention, the die changer for exchanging the die, the plug changer for exchanging the plug, and the bending of the pipe on the outlet side of the die are provided in addition to the punching device. It is preferable to arrange one or more of the bending prevention devices.

  The die (or plug) changer is configured so that a plurality of dice (or plugs) of different dimensions (and / or shapes) are arranged and held in the order of use, and can be transferred and arranged in a predetermined position in the pipe line in order. Those are preferred. The bending prevention device is preferably configured such that, for example, a movable disk having a through hole for a tube is used so that a force in a direction opposite to the direction in which the tube tries to bend can be applied to the tube closest to the die exit side. .

  It should be noted that both the conventionally used drawing and the punching used in the present invention often require a surface pipe that has been pickled after processing. In the case of drawing, it is necessary to pickle the raw tube in order to form a strong film of lubricant before performing the bond process before processing, and after picking, pickling is necessary again to remove the lubricant. And pickling must be carried out twice. Compared to this, in the case of punching, the lubrication process before processing can be simple and the oxide scale can remain attached, so it is possible to bring the lubrication process online and incorporate it into the equipment line, which is inexpensive and efficient. A good equipment line is possible.

  As an example of the present invention, an equipment row as shown in FIG. 1 was constructed. Reference numeral 1 denotes a punching device. This device performs a punching process in which a plug 6 is inserted into a tube and floated, and this tube is continuously pushed into a die 7 by a pushing device 5 and passed. . The punching device 1 is provided with a die changing device 9, a plug changing device 8 and a bending prevention device 10 configured as described above as a preferred embodiment.

  On the entry side of the punching device 1, a tube end surface grinding device 2, a lubricant dip coating tank 3, and a drying device 4 are arranged in this order from the upstream side. The pipe end surface grinding device 2 is configured to be capable of right-angle grinding by aligning the end faces of pipes arranged on a table at right angles to the pipe axis direction with a grinding tool. The lubricant dip coating tank 3 stores a dry liquid lubricant emulsion, and the tube is immersed in the emulsion bath to apply the lubricant to the tube. The drying device 4 is configured to be able to dry the tubes after applying the lubricant arranged on the table by blowing hot air. In addition, a pipe pedestal 11 that receives the raw pipe sent from the previous process and passes it to the pipe end surface grinding device 2 is arranged on the entry side of the equipment row, and the product pipe and the product pipe are punched on the outlet side. A tube dispensing table 12 for dispensing the formed tube to a subsequent process was provided.

  Using this equipment row, a raw pipe with an oxide scale attached (= a raw pipe with a scale) having various dimensions in an outer diameter of 25 to 120 mmφ, a thickness of 2 to 8 mm, and a length of 5 to 13 m. ), The tube end face was placed at a right angle ⇒ Lubricant immersion coating ⇒ Drying ⇒ Punching was performed in order to obtain a product tube.

  On the other hand, FIG. 2 shows a manufacturing equipment line by conventional drawing as a comparative example. This equipment row comprises a tube receiving base 11 on the entry side of the drawing device 14 and a pipe payout stand 12 on the exit side. The drawing device 14 inserts the plug 6 into the tube and floats it. The tube is extracted from the die 7 by the drawing device 14. The drawing device 14 is provided with a plug changing device 8 and a die changing device 9 configured in the same manner as in the embodiment. In this equipment row, the same scaled pipe as in the embodiment cannot be pulled out as it is, and the pipe that has undergone the first pretreatment step and the second pretreatment step shown in FIG. There is.

  The first pretreatment process is indispensable as a means to form a strong lubricating film for drawing, and the scaled tube is cut into a short length ⇒ the scale is removed by pickling ⇒ the acid is neutralized with an alkali ⇒ washed with water ⇒ Bonding process ⇒ Applying metal soap ⇒ Drying consists of many sequential steps. The plurality of immersion tanks or apparatuses that perform the first pretreatment process are provided in separate lines because productivity decreases when they are provided in the same line as the drawing apparatus 14. Further, the second pretreatment step is indispensable as a means for performing the lip processing of the tube tip using, for example, a rotary forging machine so as to be gripped by the drawing apparatus 14, and this rotary forging machine is also the same as the drawing apparatus 14. Since productivity decreases when deployed on the line, it is deployed on another line.

  Using the equipment row of this comparative example, the pre-processed pipes obtained by sequentially processing the raw pipes with the same scale as the examples in the first and second pre-processing steps were subjected to drawing processing to obtain product pipes. .

  Table 1 shows the required manufacturing time and the dimensional accuracy of the product pipes examined for the examples and comparative examples. The time required for production is evaluated by the total processing time / total number of processed pipes until a product pipe is obtained from a raw pipe with a scale of a predetermined number of lots. Table 1 shows the evaluation value of the comparative example as 1 and the relative ratio. It was. Dimensional accuracy is indicated by thickness deviation and outer diameter deviation. These deviations were obtained from the data obtained by image analysis of the circumferential cross section of the pipe, with the thickness deviation as a value relative to the average thickness and the outer diameter deviation as a value relative to the true circle (target outer diameter).

  As is apparent from Table 1, a high dimensional accuracy tube could be efficiently manufactured according to the present invention.

It is a schematic diagram which shows arrangement | positioning of the equipment row | line as the Example of this invention. It is a schematic diagram which shows the pre-processing process required for arrangement | positioning of an equipment row | line | column used as a comparative example, and drawing processing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Punching device 2 Pipe end surface grinding device 3 Lubricant dip coating tank 4 Drying device 5 Pushing device 6 Plug 7 Die 8 Plug change device 9 Die change device 10 Bending prevention device 11 Pipe receiving stand 12 Pipe discharge stand 13 Comparison example Production equipment line 14 by drawing process

Claims (4)

  It is a manufacturing equipment row of high dimensional accuracy pipes having a punching device that inserts a plug into a pipe and floats it, and pushes the pipe into a die, and passes through the die, and the pipe end face is ground at right angles to the pipe axis direction A grinding device, a lubricant dip coating tank for dip-coating the lubricant on the pipe, a drying device for drying the pipe coated with the lubricant, and the punching device are arranged in this order. Manufacturing equipment line for dimensional accuracy tubes.   The high-precision pipe manufacturing equipment row according to claim 1, wherein a cutting device for cutting the tube into a short length is disposed on the inlet side of the tube end surface grinding device.   Instead of the lubricant dip coating tank and the drying device, a lubricant spray coating device for spraying and applying a lubricant to the pipe on the die entrance side of the punching processing device, or drying after spraying and applying the lubricant to the tube The apparatus for manufacturing a high-dimensional accuracy tube according to claim 1, wherein a lubricant spray coating and drying device is disposed.   One or more of a die changing device for exchanging the die, a plug changing device for exchanging the plug, and a bend preventing device for preventing the bending of the pipe on the die exit side. The manufacturing equipment row of the high dimensional accuracy pipe according to any one of claims 1 to 3, wherein

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