JP2007014994A - Method for producing tapered steel pipe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a tapered steel pipe capable of forming a tapered steel pipe having a high reduction of area without enlarging a squeezing device. <P>SOLUTION: In the method for producing a tapered steel tube where a squeezing roller R in a squeezing device S is abutted on the circumferential face of a steel pipe, and the steel pipe is subjected to taper working, the taper working is performed using the squeezing roller R in which the working face abutted on the steel pipe is composed of a plurality of roller simple substances relatively rotating each other. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a tapered steel pipe, and in particular, a method for manufacturing a tapered steel pipe capable of processing a product having a large drawing ratio when plastic processing a long steel pipe (pipe) into a tapered steel pipe under a heating atmosphere. About.

The outline of the conventional taper steel pipe processing machine which processes a long steel pipe (pipe) into a taper steel pipe is shown in FIG.5 and FIG.6.
A taper steel pipe processing machine 1 used for manufacturing this taper steel pipe is a machine for plastically processing a long pipe material W into a taper steel pipe in a heated atmosphere, and a tension-side rotating mechanism base 2 placed on a frame 4; The drive side rotation mechanism base 3 placed on the frame 5, the drawing device S and the heating device H disposed between the frames 4 and 5, the tension side rotation mechanism table 2 and the drive side rotation mechanism. The table 3 is provided with driving means 2a and 3a, respectively, and is configured to be movable on the frames 4 and 5 in the axial direction. The configuration of the drive means 2a, 3a is not particularly limited, but the tension-side rotating mechanism base is configured by meshing a pinion that is rotated by a servo motor, a hydraulic motor, or the like with racks laid on both the frames 4, 5 2. It is preferable that the drive side rotating mechanism base 3 is configured to be shifted.

  The drive side rotation mechanism base 3 is provided with shaft rotation means 3b to drive the pipe material W to rotate. The tension side rotation mechanism base 2 may be provided with a rotation means by a synchronous drive control mechanism (not shown), but it is preferably configured to be supported rotatably by a bearing or the like and to be driven by a single mechanism.

  In the method of manufacturing a tapered steel pipe using the tapered steel pipe processing machine 1 having the above-described configuration, first, the pipe forming end side of the pipe material W is gripped by the loader mechanism (not shown) or the gripping device 7 of the driving side rotating mechanism base 3 by hand. Attach to. Then, when the driving side rotating mechanism base 3 is moved to the tension side rotating mechanism base 2 by the driving means 3a and the pipe forming start end side of the pipe material W is gripped on the tension side rotating mechanism base 2 side, the driving side rotating mechanism base 3 is The driving means 3a is stopped, the pipe material W is rotated at a high speed by the shaft rotating means 3b, and a tensile force is applied to the left side of the drawing by the driving means 2a of the tension side rotating mechanism base 2 so that the steel pipe is sequentially transferred and squeezed. The drawing roller R of the processing device S is brought into contact with the peripheral surface of the pipe material W to start contraction (drawing).

By moving the tension side rotation mechanism base 2 by the driving means 2a, a tensile force can be applied to the pipe material W processed by the squeezing roller R when the pipe material W is sequentially transferred. According to the experiments by the present inventors, the tensile force in the direction A (see FIG. 4B) by the driving means 2a is about 20 t at both ends of the pipe material, and the holding force (the tensile force in the B direction (see FIG. 4B) by the driving means 3a). 4 (b))))) is added for about 5t, and when a long steel pipe (pipe) is plastically worked into a tapered steel pipe in a heated atmosphere, good plastic working can be performed in one operation. It can be carried out.
Needless to say, the tensile force and the holding force change in accordance with changes in pipe size, wall thickness, and the like.

  The gripping device 7 disposed at the tip of the drive side rotation mechanism base 3 passes through the heating device H, and is squeezed to the vicinity of the gripping device 7 of the pipe material W gripped by the gripping device 7 by the squeezing roller R of the drawing processing device S. When the processing is performed, the drawing process ends (see FIG. 4B), and a tapered steel pipe is manufactured (for example, see Patent Document 1).

  However, in the drawing roller R used for drawing by the tapered steel pipe processing machine 1, the abutting portion of the roller 20 that abuts on the material rotates at both ends to the bracket 14 by bearings 15 and 15 as shown in FIG. It is a conical integral fixed to the main shaft 13 that is freely attached, and the working area of the roller surface passes through the part a (molding roller part) to the part b (pressure roller part) as the drawing of the material proceeds. When enlarged, the pressure roller portion (b portion) having a small peripheral speed acts on the raw pipe portion (W-1) having a large peripheral speed, and a large slip occurs in the b portion. This becomes a processing resistance, and there is a problem that forming a tapered steel pipe having a large drawing ratio is a significant limitation in terms of quality and production efficiency.

Also, the drawing ratio of the drawing roller is large with respect to the material, that is, it can be improved by increasing the size of the drawing roller, but increasing the size of the drawing roller is the size of the entire drawing device However, there is a problem that the equipment cost increases and the running cost increases during operation.
JP 2002-292433 A

  The present invention has been made in view of the above-described problems of the conventional squeezing rollers, and an object of the present invention is to provide a method for manufacturing a tapered steel pipe capable of forming a tapered steel pipe having a large squeezing ratio without increasing the size of the drawing device. And

  In order to achieve the above object, a taper steel pipe manufacturing method of the present invention is a taper steel pipe manufacturing method in which a steel pipe is tapered by abutting a drawing roller of a drawing device on the peripheral surface of the steel pipe. The processing surface is tapered by using a squeezing roller constituted by a plurality of rollers that rotate relative to each other.

  In this case, taper processing is performed using a squeezing roller including a main shaft rotatably disposed on the bracket, a first roller fixed to the main shaft, and a second roller rotatably disposed on the main shaft. be able to.

  In this case, taper is performed using a squeezing roller comprising a main shaft fixed to the bracket, a first roller rotatably disposed on the main shaft, and a second roller rotatably disposed on the first roller. Can be processed.

  In these cases, the second roller can be divided into a plurality of single rollers.

  According to the method for manufacturing a tapered steel pipe of the present invention, since the processing surface of the squeezing roller abutting on the steel pipe is tapered using a squeezing roller constituted by a plurality of rollers that rotate relative to each other, each roller is uniquely provided. By rotating, it is possible to reduce the occurrence of slip and form a tapered steel pipe having a large drawing ratio.

  In addition, since the main shaft is configured to be rotatable on the bracket, the first roller is fixed to the main shaft, and the second roller is rotatably disposed on the main shaft. It can be rotated separately. Therefore, only the second roller portion where the peripheral speed is increased is not worn first, and the bearing supporting the second roller only needs to be able to withstand the rotational speed of the difference in peripheral speed with the first roller. Since a tapered steel pipe can be manufactured using a squeezing roller that can use an inexpensive bearing and only the second roller portion can be replaced, a tapered steel pipe having a high squeezing rate can be formed while keeping the manufacturing cost low. Can do.

  The same effect can be obtained when the main shaft is fixed to the bracket, the first roller is rotatably disposed on the main shaft, and the second roller is rotatably disposed on the first roller. it can.

  Further, when the second roller is divided into a plurality of single rollers, it is possible to cope with a small difference in peripheral speed and to further improve the aperture ratio.

  Embodiments of a squeeze roller according to the present invention will be described below with reference to the drawings.

FIG. 1 shows an example in which a squeezing roller used in the method for manufacturing a tapered steel pipe of the present invention is used in a tapered steel pipe processing machine for manufacturing a tapered steel pipe similar to the conventional example.
The squeezing roller 10 used in the method of manufacturing a tapered steel pipe according to the present invention is configured such that the processing surface of the squeezing roller 10 that contacts the steel pipe is composed of a plurality of rollers that rotate relative to each other. A single roller constituting a continuous curved surface is used.
The squeezing roller 10 includes a large-diameter first roller 11 fixed to a main shaft 13 rotatably disposed on a bracket 14 and a small-diameter second roller 12 rotatably attached to the main shaft 13. These rollers form a conical roller surface. The main shaft 13 is composed of a large-diameter portion 13a at the center portion, a middle-diameter portion 13b at the end on the second roller 12 side serving as a pressure roller, and a small-diameter portion 13c at the end on the first roller side serving as a forming roller. A medium diameter portion 13b and a small diameter portion 13c are rotatably attached to the brackets 14a and 14b via bearings 15a and 15b, respectively. The outer diameters of the medium diameter portion 13b and the small diameter portion 13c are not particularly limited as long as they can withstand the load during the drawing process. The end (13c) may have a larger diameter than the opposite side (13b).
Further, if the first roller 11 is fixed to the main shaft 13, the main shaft 13 may not be a stepped shaft but may have a constant diameter.

The first roller 11 is fixed to the step portion between the large diameter portion 13a and the small diameter portion 13c of the main shaft 13 with a fixing member such as a bolt as shown in the figure, and is integrally formed with the main shaft 13 by cutting or the like. Also good.
The second roller 12 is rotatably attached to the large-diameter portion 13a of the main shaft 13 via a bearing 16 for the second roller. The second roller 12 is divided and formed into a roller peripheral portion 12a that comes into contact with the material W and a roller boss portion 12b that fits into the bearing 16, and the roller peripheral portion 12a is fixed to the roller boss portion 12b by fixing means such as a bolt. Moreover, you may comprise the roller peripheral part 12a and the roller boss | hub part 12b integrally. In the case where the roller peripheral portion 12a and the roller boss portion 12b are divided and configured, only the roller peripheral portion 12a can be replaced, and the maintenance cost can be further reduced.
A minute gap M (see FIG. 1B) is provided between the side surfaces of both the rollers 11 and 12, and the peripheral portion of the first roller 11 and the peripheral portion 12a of the second roller 12 are continuous protrusions. A circumferential surface is formed.
Then, as shown in FIG. 1B (enlarged view of portion X in FIG. 1A), the matching corners of both rollers 11 and 12 are chamfered (11r, 12ar), and the second roller 12 The roller peripheral portion 12 a is slightly protruded by L (about 1 mm) from the peripheral portion of the first roller 11 to prevent the scale from being caught between the rollers 11 and 12.

  Since the squeezing roller 10 has the above-described configuration, as the drawing process of the material proceeds, even if a difference in circumferential speed occurs on the roller surface in contact with the material, the circumferential speed of the second roller 12 increases. Since the portion 12a is rotatably attached to the main shaft 13 that rotates integrally with the first roller 11 via a bearing 16, it can rotate more than the first roller 11 by a difference in peripheral speed. Yes, slip and machining resistance due to the peripheral speed difference can be greatly reduced. According to experiments by the inventors, it is possible to squeeze a steel pipe having an outer diameter of 216.3 mm to about 73 mm (squeezing rate 65% or more), and to about 93% of the workable surface K of the squeezing roller 10. Even if deep drawing was performed, it was possible to process without causing product quality degradation due to slip or processing resistance.

  Next, a second embodiment of the squeeze roller shown in FIG. 2 for use in the method for manufacturing a tapered steel pipe of the present invention will be described. This squeezing roller 10 shows an example in which the second roller 12 is divided into a plurality of pieces (in the example shown, three second roller units 12c, a second roller unit 12d, and a second roller unit 12e) in a ring shape. The second roller units 12c, 12d, and 12e are rotatably disposed on the main shaft 13 via bearings 16a, 16b, and 16c. A circumferential groove is formed between the side surfaces of the second roller 12, and the frictional resistance between the side surfaces of the second roller 12 is reduced by disposing the thrust ball bearing SB in the circumferential groove.

  Since the second roller 12 is divided into a plurality of rollers in a ring shape, the contact area between the second roller 12 and the material increases as the drawing process proceeds, and the peripheral speed difference between the first roller 11 and the second roller 12 increases. Although gradually expanding, the speed difference can be effectively absorbed by rotating each of the second rollers 12c, 12d, and 12e separately, which causes a reduction in product quality due to slip and processing resistance. There is no.

  Next, a third embodiment of the squeeze roller shown in FIG. 3 for use in the method for manufacturing a tapered steel pipe of the present invention will be described. The squeezing roller 10 includes a main shaft 13 fixed to a bracket (not shown), a first roller 11 rotatably disposed on the main shaft 13 via a bearing 15, and a bearing 16 on the first roller 11. It consists of the 2nd roller 12 arrange | positioned rotatably.

  Like the second embodiment, the second roller 12 is divided into three second roller single members 12c, a second roller single member 12d, and a second roller single member 12e in a ring shape in the example shown in the drawing, and bearings 16a and 16b are respectively provided. In this example, the first roller 11 is rotatably arranged via 16c. However, as in the first embodiment, it may be non-divided.

  As the drawing of the material progresses, each portion of the second roller 12 whose peripheral speed is increased is supported by the main shaft 13 by the bearing 15 and rotates even if a difference in peripheral speed occurs on the roller surface in contact with the material. Since the first roller 11 is rotatably attached to the first roller 11 via a bearing 16, it rotates more than the first roller 11 by the difference in peripheral speed, and the same effect as in the first and second embodiments. And the main shaft 13 only needs to be fixed to the bracket, and the configuration can be simplified.

  Further, as shown in FIG. 3B, predetermined side corners 11r and 12r of the first roller 11 and the second roller 12 and the side corners of the second rollers 12 in the divided configuration are predetermined. It is preferable to form a chamfer with a radius r. As a result, it is possible to effectively prevent problems such as biting the scale during processing and scratching the material.

Next, a fourth embodiment of the squeeze roller used in the method for manufacturing a tapered steel pipe of the present invention shown in FIG. 4 will be described.
This squeezing roller is different from the first embodiment (see FIG. 1) only in the following points, and the description of the same configuration is omitted. The squeezing roller 10 is a roller in which a ring-shaped roller 12a ′ is rotatably fitted in a notch 12a-1 of the roller peripheral portion 12a between the first roller 11 and the second roller 12 in the second roller. It is.
A continuous processing peripheral surface is formed by the peripheral surface of the first roller 11, the peripheral surface of the roller 12a ', and the peripheral surface of the roller peripheral portion 12a.
The radial load received by the roller 12a ′ during processing is supported by the notch 12a-1 of the roller peripheral portion 12a, and the thrust load received by the roller 12a ′ is supported by the side surface of the first roller 11. A continuous working peripheral surface is formed by three members, and the matching side corners of each roller are the same as in the first embodiment as shown in FIG.

  As mentioned above, although the manufacturing method of the taper steel pipe of this invention was demonstrated based on several Example, this invention is not limited to the structure described in the said Example, In the range which does not deviate from the meaning, the The configuration can be changed.

  As mentioned above, the manufacturing method of the tapered steel pipe of the present invention reduces the abnormal wear due to the peripheral speed difference of the roller surface by dividing the squeezing roller used in the spinning machine into the first roller and the second roller, and reduces the squeezing rate. In addition to being able to be used to manufacture tapered steel pipes with new equipment, it can be used by replacing the squeeze rollers in existing spinning machines, for example. Can do.

The 1st Example of the squeeze roller used for the manufacturing method of the taper steel pipe of the present invention is shown, (a) is a front view of a partial cross section, (b) is a detailed view of X part of (a), ( c) is a partially cutaway view for explaining the workable surface of the squeeze roller. It is a front view of the partial cross section of 2nd Example of the squeeze roller used for the manufacturing method of the taper steel pipe of this invention. The 3rd Example of the squeeze roller used for the manufacturing method of the taper steel pipe of this invention is shown, (a) is a front view of a partial cross section, (b) is a detailed view of a mating side corner. The 4th Example of the squeezing roller used for the manufacturing method of the taper steel pipe of this invention is shown, (a) is a front view of a partial cross section, (b) is a detailed view of the Y part of (a). It is the schematic of the manufacturing method of a taper steel pipe. It is a front view of the partial cross section of the squeeze roller used for the manufacturing method of the conventional taper steel pipe.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Diaphragm roller 11 1st roller 12 2nd roller 12a Roller peripheral part 12b Roller boss part 12c Single 2nd roller 12d Single 2nd roller 12e Single 2nd roller 13 Spindle

Claims (4)

  In a taper steel pipe manufacturing method in which a steel pipe is tapered by abutting a squeezing roller of a squeezing device on the peripheral surface of the steel pipe, a squeezing roller comprising a plurality of single rollers that rotate relative to each other on the processing surface of the squeezing roller that abuts the steel pipe. A method for producing a tapered steel pipe, wherein the taper machining is performed.   A taper is formed by using a squeezing roller including a main shaft that is rotatably disposed on the bracket, a first roller fixed to the main shaft, and a second roller that is rotatably disposed on the main shaft. The manufacturing method of the taper steel pipe of Claim 1.   Tapering using a squeezing roller comprising a main shaft fixed to the bracket, a first roller rotatably disposed on the main shaft, and a second roller rotatably disposed on the first roller; The method for manufacturing a tapered steel pipe according to claim 1, wherein:   4. The method of manufacturing a tapered steel pipe according to claim 2, wherein the second roller is tapered by using a squeezing roller that is divided into a plurality of single rollers.

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