JP2018103231A - Shell manufacturing apparatus and shell manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a proper work of welding and a smooth finish of a butting part by correcting a vicinity of two end faces parallel with an axial direction in a cylindrical workpiece into a circular arc form of predetermined curvature to make the butting part butt over the whole region in a thickness direction.SOLUTION: A roll molding device 2 that bends a workpiece W into a cylindrical form and a shell welding device 6 that welds butting parts of two ends parallel with an axial direction of the workpiece W over the whole length keep a tube shrinkage device 4 arranged between them which reduces the diameter of the cylindrical workpiece W by compressing the cylindrical workpiece W over the whole periphery from the outer peripheral side.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a tubular body manufacturing apparatus and a tubular body manufacturing method for manufacturing a tubular body by bending a metal plate material into a cylindrical shape and then welding the butted portions of two end faces parallel to the axial direction.

  When forming a cylindrical metal thin-walled tube, there is a method in which a metal plate is bent into a cylindrical shape using a roll forming apparatus and two end faces parallel to the axial direction are welded. As a device used for welding two end faces parallel to the axial direction of a cylindrical workpiece, a pipe welding device including a die having a through hole through which the cylindrical workpiece passes has been proposed (for example, Patent Documents). 1).

  The pipe welding device exposes a welding tool to a part of the through hole in the axial direction and places the welding tool on the mold. While the workpiece passes through the through hole, the work abutting part is located at the welding position where the welding tool is placed. Weld. An alignment guide blade is exposed in the through hole upstream of the welding position in the workpiece passing direction. The exposed position of the guide blade in the circumferential direction of the through hole coincides with the exposed position of the welding tool. The guide blade is fitted into the abutting portion of the workpiece to prevent the rotation of the workpiece in the through hole, and the welding portion of the workpiece is opposed to the welding tool over the entire length in the axial direction to prevent the welding line from being shifted in the workpiece.

By disposing the tube welding device at the subsequent stage of the roll forming device, it is possible to configure a tube manufacturing device for manufacturing a tube having a circular cross section from a metal plate material.
Japanese Patent Publication No. 2-15310

 However, if a metal plate is bent into a cylindrical shape with a roll forming device, the vicinity of the two end faces parallel to the axial direction opens outward after the bending, and the cross-sectional shape of this part becomes a straight line or the radius increases. The arc does not have a predetermined curvature. This is a phenomenon called springback in which the internal stress generated in the plate material by bending is released at the end of the plate material and returns to the plate shape, and becomes more prominent as the plate material is bent to a smaller diameter.

  In this way, if the vicinity of the two end faces parallel to the axial direction remains open to the outside, the two end faces cannot be brought into contact with each other in the thickness direction, and the outer peripheral side opens at the butted portion of the two end faces. Further, a V-shaped gap is generated, and proper welding cannot be performed by the pipe welding apparatus, and the butt portion cannot be smoothly finished.

  An object of the present invention is to correct a cylindrical end of a two-end surface parallel to the axial direction by applying a contraction process to a cylindrical workpiece between bending and welding, thereby matching the ends. An object of the present invention is to provide a tubular body manufacturing apparatus in which welding can be appropriately performed by bringing the portion into contact with the entire region in the thickness direction, and the butted portion can be smoothly finished.

  The tubular body manufacturing apparatus according to the present invention includes a roll forming device, a reduced tube device, and a tubular body welding device. The roll forming apparatus bends a metal plate material into a cylindrical workpiece. The contraction device is arranged at the rear stage of the roll forming device, and compresses the cylindrical workpiece from the outer peripheral side over the entire circumference to reduce the diameter of the cylindrical workpiece. The tubular body welding device is disposed at the rear stage of the reduced tube device, and welds the butted portions of the two end faces parallel to the axial direction of the cylindrical workpiece over the entire length.

  In the tubular body manufacturing method of the present invention, the bending process, the contraction process, and the welding process are executed in this order. In the bending process, a metal plate material is bent into a cylindrical workpiece. In the tube contraction process, the diameter of the cylindrical workpiece is reduced by compressing the cylindrical workpiece from the outer peripheral side over the entire circumference. In the welding process, the butted portions of the two end faces parallel to the axial direction of the cylindrical workpiece are welded over the entire length.

The cylindrical workpiece is subjected to a tube shrinking process before the welding process, the vicinity of the two end faces parallel to the axial direction is corrected to an arc shape with a predetermined curvature, and the abutting portion in a state of being in contact with the entire area in the thickness direction is provided. Welded. The cylindrical workpiece is formed into a tubular body with a smooth butted portion by appropriate welding.

  In this configuration, the contraction tube device includes a conveyance device that intermittently conveys the cylindrical workpiece, and compresses the cylindrical workpiece from the outer peripheral side over the entire circumference at each position where the cylindrical workpiece is divided into a plurality of portions in the axial direction. Preferably. It is possible to use a small-sized tube contraction device having a tube contraction length shorter than the axial length of the cylindrical workpiece.

  According to the present invention, the abutting portion of the cylindrical workpiece is brought into contact with the entire region in the thickness direction, so that welding can be appropriately performed, and a tubular body having a smooth abutting portion can be manufactured.

1 is a plan view of a tubular body manufacturing apparatus according to an embodiment of the present invention. It is the schematic of the roll shaping | molding apparatus used for the tube manufacturing apparatus. (A)-(D) are figures which show the bending process in the roll forming apparatus. (A) And (B) is the side view and sectional drawing of a reduced tube apparatus used for the same pipe body manufacturing apparatus. It is sectional drawing of the workpiece | work which shows the contracted tube state in the tube manufacturing apparatus. It is the schematic of the pipe welding apparatus used for the pipe manufacturing apparatus.

  Hereinafter, a tubular body manufacturing apparatus and a tubular body manufacturing method according to an embodiment of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, a pipe body manufacturing apparatus 10 according to an embodiment of the present invention includes a work stocker 1, a roll forming apparatus 2, a transport apparatus 3, a contraction pipe apparatus 4, a loader 5, and a pipe body welding apparatus 6. Yes.

  The work stocker 1 carries a metal plate material, which is a material of a tubular body manufactured by the tubular body manufacturing apparatus 10, into the roll forming apparatus 2 one by one.

  As shown in FIG. 2, the roll forming apparatus 2 includes a frame 21, a main roll 22, a sub roll 23, a pressing roll 24, a first motor 25, a second motor 26, a moving mechanism 27, a support body 28, and a fixing member 29. As an example, a workpiece W made of a metal plate material having plasticity, which is high-tensile steel, is formed into a cylindrical shape having a relatively small diameter by bending.

  The frame 21 is a rigid body having a portal shape when viewed from the front. The main roll 22 is pivotally supported by the frame 21 at a first end (right end in FIG. 2) 221 and is fixed to the rotation shaft of the first motor 25. The two front and rear sub-rolls 23 are axially supported by the holding base 231 below the main roll 22 with the axial direction parallel to the main roll 22, and the second motor 26 is connected to both ends via the universal joints 261. The rotation axis is fixed. The pressing rolls 24 are pivotally supported on the holding table 231 with the axial direction parallel to the two sub-rolls 23 at three places in the front-rear direction. The holding table 231 is supported by the frame 21 so as to be movable up and down in a state where movement in the horizontal direction is restricted.

  The first motor 25 and the second motor 26 are constituted by pulse motors as an example, and are attached to the frame 21. The roll forming apparatus 2 includes a total of four second motors 26, but depending on the workability of the workpiece W, only one end of each of the two sub-rolls 23 or the two sub-rolls 23. A total of 22 second motors 26 may be arranged at each end.

  A moving mechanism 27 is disposed below the holding table 231. The moving mechanism 27 includes a slider 271, a lift motor 272, and a ball screw 273. The slider 271 is held movably along the axial direction of the main roll 22 in a state where the rotation is restricted by the frame 21. The lift motor 272 is a pulse motor as an example, and supplies the rotation of the rotary shaft to the ball screw 273. The ball screw 273 is screwed into the female screw portion of the slider 271 from one side surface.

  When the elevating motor 272 is rotated forward or backward, the ball screw 273 rotates and the screwing position with the female screw portion is changed. The slider 271 reciprocates along the axial direction of the main roll 22 by changing the screwing position of the ball screw 273 and the female screw portion. An inclined surface 274 is formed on the upper surface of the slider 271. A protrusion 232 protruding from the lower surface of the holding table 231 is in contact with the inclined surface 274. When the slider 271 reciprocates along the axial direction of the main roll 22, the holding base 231 moves up and down together with the two sub rolls 23 and the three pressing rolls 24.

  When bending the workpiece W by the roll forming apparatus 2, first, as shown in FIG. 3A, the plate-like workpiece W and the main roll 22 and the sub-roller are brought to a position where the first end W1 is in contact with the main roll 22. It is carried in between the rolls 23 in the horizontal direction.

  Next, the holding table 231 is raised and the sub roll 23 is positioned at the molding position. When the sub roll 23 reaches the forming position, the first motor 25 rotates forward and the main roll 22 rotates counterclockwise in FIG. 3, and the second motor 26 reverses and the sub roll 23 rotates in the clockwise direction in FIG. Rotate in the direction and execute the forward rotation process. Thereby, the workpiece W is curved along the peripheral surface of the main roll 22 while moving in the right direction in FIG. 3.

  When the workpiece W is curved and moves to the right in FIG. 3 and the central portion W3 of the workpiece W comes into contact with the peripheral surface of the main roll 22, the elevating motor 272 is reversely driven by a predetermined number of pulses, and the sub-roll 23 is retracted. Descending until the transfer process is executed. This timing is determined by the number of drive pulses of the first motor 25 from the start of forward rotation of the first motor 25 and reverse rotation of the second motor 26, for example. As a result, the workpiece W moves to the right side in FIG. 3 while the left portion of the center portion W3 remains flat.

  Since the sub roll 23 is gradually lowered by the elastic force of the spring 233, even when the work W is in close contact with the peripheral surface of the main roll 22, the work W can be reliably moved to the right side in FIG. it can. However, another elastic member such as a damper can be used instead of the spring 233, and the elastic member may be omitted when the workpiece W does not adhere to the peripheral surface of the main roll 22.

  As shown in FIG. 3C, when the second end W2 of the workpiece W reaches a position where it abuts on the peripheral surface of the main roll 22, the forward rotation of the first motor 25 and the reverse rotation of the second motor 26 are temporarily stopped. Then, the elevating motor 272 rotates forward and the sub-roll 23 is raised to the molding position. This timing is determined by the number of drive pulses of the first motor 25 from the start of forward rotation of the first motor 25 and reverse rotation of the second motor 26, for example. At the same time, the first motor 25 rotates in the reverse direction, the main roll 22 rotates in the clockwise direction in FIG. 3, the second motor 26 rotates in the normal direction, and the sub roll 23 rotates in the counterclockwise direction in FIG. To do. As a result, the workpiece W moves to the left side in FIG. 3, and the portion on the right side of the second end W2 is curved along the peripheral surface of the main roll 22.

  As shown in FIG. 3D, when the central portion W3 of the workpiece W reaches the position where it comes into contact with the main roll 22 again, the reverse rotation of the first motor 25 and the normal rotation of the second motor 26 are stopped, and the lifting motor 272 reverses and the sub roll 23 descends to the retracted position. This timing is determined, for example, by the number of drive pulses of the first motor 25 from the start of reverse rotation of the first motor 25 and normal rotation of the second motor 26.

  Thus, the workpiece W is also curved from the second end W2 to the central portion W3 with the same radius of curvature as that from the first end W1 to the central portion W3, and the workpiece W is formed into a cylindrical shape. .

  The conveyance device 3 conveys the cylindrical workpiece W bent by the roll forming device 2 along the axial direction of the workpiece W toward the contraction tube device 4 arranged at the rear stage of the roll forming device 2. The conveyance of the work W by the conveyance device 3 is synchronized with the contraction processing of the workpiece W in the contraction device 4.

  In other words, the tube length of the tube contraction device 4 in the axial direction of the workpiece W is shorter than the entire length of the workpiece W, and the tube contraction device 4 performs tube contraction over the entire length in a plurality of times in the axial direction of one workpiece W. . For this reason, the conveying device 3 intermittently conveys the workpiece W by a distance shorter than the reduced tube length of the reduced tube device 4 by a predetermined length, and the reduced tube device 4 interrupts the transfer of the workpiece W by the conveying device 3. The work W is contracted during the operation. By repeating this conveyance and contraction a predetermined number of times, the workpiece W is contracted over the entire length.

  As shown in FIGS. 4A and 4B, the contraction device 4 includes a mold 41, a slider 42, a follower 43, and a hydraulic cylinder 44. The die 41 is configured in eight divisions as an example along the circumferential direction of the workpiece W, and eight sliders 42, followers 43, and hydraulic cylinders 44 are arranged corresponding to each of the eight die 41. ing.

  The eight molds 41 are movable along the radial direction between a position where they are in contact with each other and a position where they are separated along the circumferential direction. When the eight molds 41 are in contact with each other, a cylindrical space is formed by their inner side surfaces. The inner diameter of the cylindrical space formed by the inner peripheral surface of the mold 41 is about 0.3 to 0.7% smaller than the outer diameter of the workpiece W bent into a cylindrical shape by the roll forming apparatus 2.

  The hydraulic cylinder 44 includes a piston 441 that is movable along the axial direction of the workpiece W. A slider 42 is fixed to the piston 441. The slider 42 includes an inclined surface 421. The follower 43 is fixed to the mold 41 and includes an inclined surface 431 that contacts the inclined surface 421.

  As shown on the upper side in FIG. 4 (B), in a state in which pressure oil is supplied to the right side of the piston 441 in the hydraulic cylinder 44 in the drawing, the piston 441 is located on the left side in the drawing, and the follower 43 and the mold 41 are located. Are not pressed by the slider 421, and the eight molds 41 are at positions separated from each other. At this time, a space sufficiently larger than the outer diameter of the workpiece W is formed inside the eight molds 41.

  As shown on the lower side in FIG. 4B, in a state where pressure oil is supplied to the left side of the piston 441 in the hydraulic cylinder 44 in the drawing, the piston 441 is located on the right side in the drawing, and the follower 43 and the mold 41 is pressed by the slider 421, and the eight molds 41 are in contact with each other. At this time, a cylindrical space smaller than the outer diameter of the workpiece W is formed inside the eight molds 41.

  Pressure oil is supplied to the right side in the figure of the pistons 441 in the eight hydraulic cylinders 44, and the workpieces W are moved to the eight molds 41 by the transfer device 3 in a state where the eight molds 41 are spaced from each other. Carry into the inner space. Thereafter, pressure oil is supplied to the left side of the piston 441 in the hydraulic cylinder 44 in the drawing, and the eight dies 41 are moved to positions in contact with each other, whereby the outer diameter of the workpiece W is reduced.

  As described above, the contraction processing of the contraction device 4 is performed in synchronization with the transport processing of the transport device 3. For example, when the axial length of the bent cylindrical workpiece W is L and the axial length of the mold 41 in the tube contracting device 4 is S = L / 2, eight dies In a state where the molds 41 are separated from each other, the workpiece W is conveyed along the arrow X direction by the conveying device 3 until the upstream end of the workpiece W reaches the vicinity of the right end in the mold 41 shown in FIG. To do.

  Here, pressure oil is supplied to the left side of the piston 441 in the hydraulic cylinder 44 in the drawing, and the eight molds 41 are moved to positions where they abut against each other. Next, after supplying pressure oil to the right side of the piston 441 in the drawing in the hydraulic cylinder 44 and separating the eight dies 41 from each other, the workpiece W is moved by the distance (Sd) in the direction of the arrow X by the transport device 3. Convey along. After the conveyance of the workpiece W by the conveyance device 3 is stopped, the pressure oil is again supplied to the left side of the piston 441 in the hydraulic cylinder 44 in the drawing, and the eight molds 41 are moved to positions where they abut against each other.

  Furthermore, after supplying pressure oil to the right side of the piston 441 in the drawing in the hydraulic cylinder 44 and separating the eight dies 41 from each other, the workpiece W is moved by the distance (Sd) in the direction of the arrow X by the transport device 3. The hydraulic fluid is supplied to the left side of the piston 441 in the hydraulic cylinder 44 again, and the eight molds 41 are moved to positions where they abut against each other. Let At this time, by appropriately selecting the length of the distance d, the downstream end of the workpiece W can be positioned in the mold 41, and the workpiece W is partially over the entire length by the three times of tube contraction processing. It can be wrapped and contracted.

  As shown by a one-dot chain line in FIG. 5, the vicinity of the two end faces parallel to the axial direction of the workpiece W bent into a cylindrical shape by the roll forming device 2 is opened to the outside by the spring back, and is brought into contact with the abutting portion W4 of the two end faces. Is formed with a V-shaped gap opened outward. In this state, the butted portion W4 cannot be properly welded, and a tubular body having a smooth circumferential surface cannot be formed over the entire length and the entire circumference.

  Therefore, the work W formed in a cylindrical shape by bending is subjected to a tube contraction process by the tube contractor 4 before the welding process, thereby pressing the work W from the outside over the entire circumference. As a result, the workpiece W has a circular cross-sectional shape including the vicinity of the two end faces parallel to the axial direction, and the two end faces come into contact with each other in the thickness direction at the abutting portion W4. Appropriate welding can be performed on the abutting portion W4 so as to form a tubular body.

  The loader 5 loads the workpiece W, which has been subjected to the tube contraction over the entire length, into the tube welding apparatus 6 along a direction orthogonal to the axial direction.

  In the contraction processing, in order to bring the cross section of the workpiece W close to a perfect circle, the circumferential surface of the cylindrical workpiece W should be pressed toward the center over the entire circumference. For this purpose, the mold 41 is preferably divided into as many pieces as possible along the circumferential direction, and about eight divisions are optimal due to the structure of the contraction device 4, but the material, thickness, and diameter of the workpiece W are optimal. Accordingly, there is a possibility that the same effect can be obtained with a smaller number of divisions.

  As shown in FIG. 6, the tube welding device 6 welds a butting portion W4 of a cylindrical workpiece W made of a metal plate material along the axial direction to manufacture a tube. The workpiece W is formed in a cylindrical shape in which a rectangular metal plate material is bent in advance and two end faces parallel to each other are butted in the circumferential direction. The tube welding apparatus 6 includes conveying rollers 61A and 61B, a guide roller 62, a preheater 63, an endless moving member 64, a guide blade 65, a welding torch 66, a first support member 67, and a second support member 68. I have.

  The transport rollers 61A and 61B are transport means of the present invention, and transport the workpiece W along a transport direction X parallel to the axial direction. The conveyance roller 61A carries the workpiece W before welding to the welding position. The conveyance roller 61B carries out the workpiece W after welding from the welding position. The transport rollers 61A and 61B can have a shape suitable for transporting the cylindrical workpiece W along the axial direction. When the length of the workpiece W in the axial direction is short, instead of one or both of the conveying rollers 61A and 61B, a pusher that presses the rear end of the workpiece W before welding along the axial direction, and after welding It is also possible to provide a puller that pulls out the tip of the workpiece W along the axial direction.

  The guide roller 62 has a disk shape with a thin peripheral edge, and is rotatably supported by the second support member 68 on the upstream side of the endless moving member 64 in the transport direction X.

  The preheater 63 is an electromagnetic induction heater as an example, and is fixed to the second support member 68 between the endless moving member and the guide roller 62 in the transport direction X. The preheater 63 preliminarily heats the welded portion of the workpiece W before welding, and facilitates subsequent welding. The preheater 63 can be omitted on condition that the welding by the welding torch 66 is properly performed.

  For example, the endless moving member 64 includes a chain 641 stretched between a pair of sprockets 642 and 643, and is disposed at seven locations around the workpiece W. The chain 641 is stretched so as to be movable along a circulation path including a straight portion. The chain 641 can be stretched around three or more sprockets. The seven endless moving members 64 are supported by the first support member 67 so that the linear portions in the circulation path of the respective chains 641 abut against the outer peripheral surface of the workpiece W.

  The guide blade 65 is a plate-like body having a thin lower end, and the longitudinal direction is set to the transport direction X within a range where the linear portion in the circulation path of the endless moving member 64 in the transport direction X is disposed. The second support member 68 is fixed in parallel.

  The welding torch 66 welds the butt W4 in the workpiece W by arc welding. The welding torch 66 is fixed to the second support member 68 within a range of a straight line portion in the circulation path of the endless moving member 64 in the transport direction X and at a position downstream of the guide blade 65.

  The first support member 67 is configured so that each of the seven endless moving members 64 moves by an equal distance along the radial direction of the workpiece W (the normal direction of the outer surface). The sprockets 642 and 643 are rotatably supported. The first support member 67 includes a base 671, a frame 672, a cam disk 673, a ring 674, and a cam follower 675, and is configured symmetrically on the upstream side and the downstream side in the transport direction X. The base 671 has a flat plate shape and is disposed horizontally. On the upper surface of the base 671, fixing portions 6711 extend from two places. The lower end portion of the frame 672 is fixed to the fixing portion 6711 by a fixing bolt 676.

  The second support member 68 supports the guide roller 62, the preheater 63, the guide blade 65, and the welding torch 66 in this order along the transport direction X. With respect to the horizontal direction in the plane orthogonal to the transport direction X, the peripheral positions of the guide roller 62, the heating part of the preheater 63, the lower end part of the guide blade 65, and the central positions of the crater of the welding torch 66 are the same. Yes.

  When the work W is loaded between the linear portions of the circulation path of the endless moving member 64 along the transport direction X with the peripheral edge of the guide roller 62 fitted in the butting portion W4, the lower end of the guide blade 65 is also butted. Fit into the part W4. While the workpiece W is being transported, the rotation of the workpiece W is regulated at a rotational position where the butting portion W4 faces the heating portion of the preheater 63 and the crater of the welding torch 66, and the butting portion W4 is heated by the preheater 63. It is welded by a welding torch 66.

  At the welding position by the welding torch 66, the guide blade 65 is detached from the abutting portion W4, and the abutting portion W4 is opposed to the welding torch 66 after the two end surfaces are returned to the state where the two end surfaces are brought into contact by the elastic force of the workpiece W. As a result, the workpiece W is appropriately welded to the abutting portion W4 so as to be a tubular body having a smooth circumferential surface over the entire length and the entire circumference.

  In addition, all said embodiment is an example, This invention is not limited to these, A various change can be added within the scope of this invention.

  For example, regarding the roll forming apparatus and the tube welding apparatus, the roll forming apparatus 2 and the tube welding apparatus 6 shown in the above embodiment are examples, and the present invention is not limited to these configurations.

1-work stocker 2-roll forming device 3-conveying device 4-condensation device 5-loader 6-tube welding device 10-tube manufacturing device 41-die W-work

Claims (4)

A roll forming apparatus for bending a metal plate material into a cylindrical workpiece;
A tube-reducing device disposed downstream of the roll forming device and compressing the cylindrical workpiece from the outer peripheral side over the entire circumference to reduce the diameter of the cylindrical workpiece;
A pipe welding device that is arranged at a subsequent stage of the tube contracting device and welds abutting portions at two ends parallel to the axial direction of the cylindrical workpiece over the entire length;
An apparatus for manufacturing a tube body.   The said tube contraction apparatus is a metal mold | die divided | segmented into multiple along the circumferential direction of the said cylindrical workpiece, Each moves to the position which mutually contact | abuts and spaces apart along the radial direction of the said cylindrical workpiece. The tubular body manufacturing apparatus according to claim 1, comprising a mold that is made free.   The tubular body manufacturing apparatus according to claim 1 or 2, wherein the contraction device includes a transport device that intermittently transports the cylindrical workpiece along the axial direction toward the contraction device.   Bending process for bending a metal plate into a cylindrical workpiece, a tube-reducing process for reducing the diameter of the cylindrical workpiece by compressing the cylindrical workpiece from the outer periphery over the entire circumference, and the cylindrical shape And a welding process for welding abutting portions of two end faces parallel to the axial direction of the workpiece over the entire length in this order.

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