Extrusion device

Abstract

The present application provides an extrusion device for resistance welded pipe manufacturing, which is simple in structure, easy to miniaturize and lighten, and excellent in economy and workability during roll changing, and has: an open U-shaped fixed base (10); and a sliding roll support plate (60) which is inserted into and held in the base from the open upper portion of the U-shaped fixed base (10) and is capable of being taken out. The roll support plate (60) movably supports a pair of left and right side rolls (40) and an upper roll (50) on the main surface on the upstream side in the pressing direction, and has a space (61) for the passage of the tubular material at a position surrounded by the rolls. The space (61) is a part of a notch-like opening portion which is open toward the lower edge of the roll support plate (60). The pair of left and right side rolls (40) are inclined rolls whose respective roll shafts (42) are inclined upward and outward.

Description

Technical Field

[0001] This invention relates to an extrusion apparatus used on a resistance welded pipe manufacturing line that continuously produces pipes from flat metal materials, and more specifically, to an extrusion apparatus with a simple structure and easy roll changing operation. Background Technology

[0002] On a resistance-welded pipe manufacturing line, a flat strip of steel, commonly known as strip steel, is gradually shaped into a cylindrical shape by forming rollers to form an open pipe. Opposite edges of this open pipe are induction heated, and then pressed by extrusion rollers to continuously weld them together, thereby continuously manufacturing cylindrical resistance-welded steel pipes. Such resistance-welded pipe manufacturing lines typically produce various types of products with different outer diameters and plate thicknesses, thus requiring frequent changes to the forming rollers.

[0003] Regarding the configuration of the extrusion rollers in the extrusion unit, for medium-diameter tubes (5-12 inches) and large-diameter tubes (13 inches and above), a five-roll configuration is generally used, consisting of a lower roller, a pair of left and right side rollers, and a pair of left and right upper rollers. The lower roller supports the open tube entering the unit from below with its opposing edges facing upwards. The pair of left and right side rollers press the open tube from both sides, and the pair of left and right upper rollers press the area near the opposing edges from an oblique upward position. During the aforementioned roller change, all these rollers are replaced with rollers corresponding to the new product size. Furthermore, for small-diameter tubes (4 inches and below), a two-roll or three-roll configuration is generally used.

[0004] In five-roll extrusion presses, due to the large number of rolls, there is a particular requirement for rapid roll changing operations. To meet this requirement, improved extrusion devices have been disclosed, for example, in Patent Documents 1 to 4.

[0005] In the extrusion apparatus shown in Patent Document 1, a main frame is mounted on a base located within the forming pipeline, and a roller support plate is detachably mounted on its material inlet side surface. A through-hole is provided on the roller support plate, and a lower roller, a pair of left and right side rollers, a pair of left and right upper rollers, and a pressing device for the upper rollers are mounted together, surrounding the through-hole. The pressing devices for the lower rollers and the side rollers are respectively mounted on the base and the main frame side. Roller changes are performed by using a crane to lift the roller support plate, the lower roller, the pair of left and right side rollers, the pair of left and right upper rollers, and the pressing device for the upper rollers together into and out of the apparatus.

[0006] In the extrusion apparatus shown in Patent Document 2, a sub-frame is assembled within a fixed main frame located inside the forming line. The sub-frame is movable and can retract to the side of the forming line. Inside the sub-frame, a lower roller, a pair of left and right side rollers, and a pair of left and right upper rollers are supported. The pressing devices for these rollers are all mounted on the side of the main frame. Roll changing is performed by retracting the sub-frame and all the rollers it supports to the side of the forming line.

[0007] In the extrusion apparatus shown in Patent Document 3, a first roller base is provided inside the forming pipeline, and a second roller base is arranged longitudinally on the downstream side of the first roller base. A lower roller and a pair of left and right side rollers are installed in the first roller base on the upstream side. On the second roller base on the downstream side, a pair of left and right upper rollers are installed on the first roller base on the upstream side via roller support plates. Roller replacement is performed by using a crane to lift the pair of left and right upper rollers and the roller support plates together from the second roller base. In this state, the pair of left and right side rollers and the lower roller are disassembled from the first roller base upwards.

[0008] In the extrusion apparatus shown in Patent Document 4, the lower roller, a pair of left and right side rollers, and a pair of left and right upper rollers are assembled in a fixed part provided within the forming pipeline, and the pair of left and right upper rollers are assembled in a movable part that overlaps the fixed part. The movable part can tilt from an upright position on the fixed part to a horizontal position. By tilting to the horizontal position, the lower surface of the movable part and the upper surface of the fixed part can be opened to allow for roller changing.

[0009] In these interchangeable roll extrusion units, various methods have been adopted to expedite roll changing operations, but problems still exist.

[0010] For example, in the extrusion device shown in Patent Document 1, all five rollers—the lower roller, a pair of left and right side rollers, and a pair of left and right upper rollers—are mounted on a roller support plate, and the pressing device for the upper rollers is also mounted on the roller support plate. Therefore, the lifting weight of the crane increases, requiring a larger lifting capacity for large-diameter pipes. In other words, the increase in size and weight of the overall equipment, including the crane, is inevitable.

[0011] In the extrusion apparatus shown in Patent Document 2, since the extrusion rollers are five rollers and the frame is a dual structure consisting of an outer fixed frame and an inner movable frame, the increase in frame size, structural complexity, and resulting weight increase are unavoidable. Moreover, in order to allow the movable sub-frame to retract to the side of the pipeline during roller changes, a standby replacement space for the sub-frame must be ensured on the side of the pipeline, increasing the space occupied.

[0012] In the extrusion apparatus shown in Patent Document 3, since the extrusion rolls are five rolls and the extrusion roll base is composed of an upper first roll base and a lower second roll base, the large size of the base frame, the complexity of the structure, and the resulting increase in weight are unavoidable. Furthermore, during roll changing, the left and right upper rolls, along with the roll support plates, are lifted upwards from the second roll base using a crane. In this state, the left and right side rolls and the lower roll are removed upwards from the first roll base, and then the rolls are assembled in the reverse order. As a result, the roll changing operation becomes more complex compared to other extrusion apparatuses.

[0013] In the extrusion device shown in Patent Document 4, the extrusion roller base consists of a fixed part and a tiltable movable part. It avoids the trouble of using a crane to lift large heavy objects such as the base frame. However, since the extrusion roller has five rollers and all of these rollers need to be lifted in and out by a crane, the number of times the crane is used for lifting is still very high.

[0014] Thus, in existing extrusion apparatuses using five extrusion rollers, the number of rollers is inherently large. Furthermore, in the extrusion apparatuses shown in Patent Documents 2 and 3, the use of two base frames (front and rear) inevitably leads to a larger apparatus size. In the extrusion apparatuses shown in Patent Documents 1 and 3, the use of roller support plates, particularly in the extrusion apparatus disclosed in Patent Document 1, effectively avoids a large apparatus size through a combination of a base frame and a roller support plate. However, to suspend the roller support plate supporting the five rollers on the material entry side surface of the base frame, multiple clamping devices are required, inevitably leading to structural complexity. Additionally, in any extrusion apparatus using a roller support plate, since the roller support plate supports not only the extrusion rollers but also the pressing device, there is a problem of excessively increased lifting weight.

[0015] In addition to these issues, such as Figure 20 As shown, in the extrusion apparatus, the opposing state of the two edges of the open tube 3 is adjusted by the finishing roll base 2 located upstream of the extrusion roll 1. However, from a position further upstream than the finishing roll 3 where the two edges of the strip are pulled apart more, the mandrel bar 4 is inserted into the open tube 3 towards the downstream side. Through the impedance device 5 installed on the mandrel bar 4, heating of the opposing edges is promoted in the area from the power supply device 6, which consists of welding contact plates and working coils, directly in front of the extrusion roll 1 to the extrusion roll 1, thereby improving welding efficiency.

[0016] In addition, depending on the type of tube being manufactured, the mandrel 4 extends further downstream, and the weld seam generated at the weld joint is cut and removed by the weld seam cutting device 8 installed at the front end of the extension 7.

[0017] Since the mandrel 4, essential for this resistance welded pipe manufacturing line, reaches at least the extrusion roller 1 regardless of its length, it is impossible to replace the extrusion roller 1 without separating the mandrel 4 from the support bracket 9 and moving it to a position downstream of the extrusion device (upstream depending on the location of the support bracket). Therefore, any extrusion device shown in Patent Documents 1-4 requires the removal and movement of the mandrel 4 during roller replacement, which is a major reason for the complexity of the roller replacement operation.

[0018] Patent Document 1: Japanese Patent Application Publication No. 59-199113

[0019] Patent Document 2: Japanese Patent Application Publication No. 05-076928

[0020] Patent Document 3: Japanese Patent Application Publication No. 08-103823

[0021] Patent Document 4: Japanese Patent Application Publication No. 2012-223782 Summary of the Invention

[0022] The purpose of this invention is to provide an extrusion apparatus that allows for simple roll changing even with medium-diameter and large-diameter tubes in a five-roll process. This apparatus is simple in structure, easily miniaturized and lightweight, and offers excellent operability and economy. Another purpose of this invention is to provide an extrusion apparatus that, in conjunction with miniaturization and lightweight design, improves tube quality.

[0023] To achieve the above objectives, the extrusion apparatus of the present invention comprises:

[0024] A U-shaped fixing base is configured on a resistance welding pipe manufacturing line. The inner side of the U-shaped fixing base allows tubular materials to pass through, and the upper part is open.

[0025] A roller support plate, which is a sliding panel that can be removed from the open upper part of the U-shaped fixed base and inserted into and held in the base, has a pair of left and right side rollers and an upper roller that can be movably supported in the pressing direction on the main surface of the upstream side of the panel. The upper roller is a single roller structure that presses the mating edge of the tubular material from directly above or a two roller structure that presses the mating edge from obliquely above. The roller support plate has space for the tubular material to pass through in a position surrounded by these rollers that do not have a lower roller.

[0026] An anti-detachment mechanism is used to fix the roller support plate inserted into the U-shaped fixed base within the base.

[0027] A first pressing device, mounted on the U-shaped fixed base, presses down the pair of left and right side rollers supported by the support plate inward while the roller support plate is fixed within the base; and

[0028] The second pressing device is installed on the U-shaped fixed base. When the roller support plate is fixed in the base, it presses down the upper roller supported by the support plate.

[0029] That is, in the extrusion apparatus of the present invention, even for medium-diameter pipes and large-diameter pipes of 5 inches or more that are conventionally used with a five-roller base, since the extrusion roller consists of a pair of side rollers and an upper roller, and the lower roller is omitted, the extrusion roller will not be obstructed when the roller support plate is pulled out from the U-shaped fixed base, and the disassembly of the extrusion roller is not required. Furthermore, since the extrusion roller is supported on the main surface of the upstream side of the roller support plate, and the roller support plate is located on the downstream side of the extrusion roller, the impedance device inserted from the upstream side of the extrusion roller into the area directly below the extrusion roller and the core rod supporting the impedance device do not interfere with the pulled-out roller support plate, and therefore it is not necessary to disassemble the core rod supporting the impedance device.

[0030] Furthermore, due to the small number of rollers in the extrusion unit, its structure is inherently simple, reducing the weight of the unit, especially the rollers. Additionally, since the extrusion roller base is an open-top U-shaped fixed base, the roller support plate can be inserted and removed through its opening. By inserting the roller support plate, all the extrusion rollers, along with the roller support plate, are simultaneously installed into the U-shaped fixed base; by pulling the roller support plate upwards from the U-shaped fixed base, all the extrusion rollers, along with the roller support plate, are simultaneously pulled out of the fixed base. This makes roller changing operations extremely simple.

[0031] During the tube manufacturing process, after the heating of the two edges of the joint is completed, the tubular material passes through the space formed in the roller support plate, and the left and right side rollers are pressed down by the first pressing device for the side rollers, and the upper roller is pressed down by the second pressing device for the upper roller, thereby applying a specified upsetting force to the heated joint edges of the tubular material.

[0032] The U-shaped fixed base not only makes it easy to replace the extrusion rollers, but also has a simple structure, is small and lightweight. In particular, its smaller dimensions along the pipeline direction are effective in shortening the pipeline length.

[0033] In the extrusion apparatus of the present invention, the anti-detachment mechanism for fixing the roller support plate within the U-shaped fixed base is, for example, an openable / closeable cover capable of opening and closing the open upper part of the U-shaped fixed base. In addition, for example, there is a pair of clamping mechanisms, respectively installed on both sides of the U-shaped fixed base and respectively engaging with the side edges of the roller support plate inserted into the base. From a weight reduction point of view, this clamping mechanism is effective.

[0034] Regarding the second pressing device for the upper roller, when the anti-detachment mechanism is the opening and closing cover, a jack-type pressing device is installed on the opening and closing cover. In this way, the opening and closing cover also serves as the mounting base for the pressing device, resulting in a simple and reasonable structure. When the anti-detachment mechanism is a pair of left and right clamping mechanisms, the jack-type pressing device, particularly the main body, is installed on a sliding upper roller mounting plate that can be raised and lowered along one main surface of the roller support plate. The drive mechanism of the main body is constructed on the other side of the roller support plate or on the other side from the roller support plate to the U-shaped fixed base. This also results in a simple and reasonable structure.

[0035] A space for the tubular material to pass through is formed in the position of the roller support plate surrounded by a pair of left and right side rollers and an upper roller. This space can also be a closed through hole, but it is particularly preferred to form part of a slit-like opening that opens downward toward the roller support plate. If the space in the roller support plate for the tubular material to pass through is part of a slit-like opening that opens downward, then when changing rollers, the extended mandrel for the inner weld grinding device will also pass through the slit-like opening without obstructing the rise of the roller support plate, and therefore the disassembly of the extended mandrel for the inner weld grinding device is not required.

[0036] Regarding the extrusion rollers in the extrusion apparatus of the present invention, the upper roller can be a single-roller structure (single type) that presses the mating edge of the tubular material from directly above, or a two-roller structure (segmented type) that presses the mating edge separately from obliquely above. When the upper roller is a single roller, the extrusion roller assembly is a three-roller structure; when there are two rollers, the extrusion roller assembly is a four-roller structure. In either case, it is simpler and lighter than a five-roller structure. For small-diameter and medium-diameter pipes, a three-roller structure is preferred; for medium-diameter and large-diameter pipes, a four-roller structure is preferred.

[0037] The left and right side rollers can also be vertical rollers with their respective roller shafts vertical, but are preferably inclined rollers with their respective roller shafts facing upwards and tilted outwards. That is, in the extrusion apparatus of the present invention, since there is no lower roller, when the side rollers are vertical rollers, these vertical rollers need to support the tubular material from below, thus becoming rollers with different diameters, where the lower flange diameter is larger than the upper flange diameter. As a result, the roller weight increases, and the difference in circumferential speed caused by the increase in the lower flange diameter easily leads to roller marks. In addition, a downward thrust is applied to the side rollers. Furthermore, in addition to increasing the lower flange diameter, from the viewpoint of avoiding interference between the vertical side roller shaft and the upper roller shaft above, it is also necessary to increase the roller diameter. The increase in roller diameter leads to an increase in the forming area in the tubing direction, resulting in a problem of an increased distance from the power supply position of the welding contact piece and the working coil to the welding point.

[0038] However, by tilting the support shafts of the left and right side rollers upwards and outwards, it is not necessary to increase the diameter of the lower flange. That is, it is possible to achieve equal diameters for the upper and lower flanges. In addition, due to its tilt, the side roller shaft is less likely to interfere with the upper roller shaft above, which also allows for a smaller diameter of the side roller. Moreover, by reducing the diameter of the side roller, including the equal diameter of the upper and lower flanges caused by the smaller diameter of the lower flange, the weight of the roller can be reduced, roller marks can be prevented, and the distance from the welding coil to the welding point can be shortened, thereby improving the tube quality while achieving a smaller and lighter device. In addition, by equalizing the diameters of the upper and lower flanges, the roller diameter is symmetrical in the roller axis direction, and the thrust is canceled out. As a result, it is also possible to reduce the size and extend the life of the bearings supporting the side rollers. Inclined rollers that support tubular materials from a downward angle are particularly effective for medium-diameter and large-diameter tubes.

[0039] The extrusion device of the present invention simplifies the device structure and makes the device smaller and lighter by combining a U-shaped fixed base and a roller support plate. Moreover, it can greatly improve the economy and workability by significantly improving the workability when changing rollers. The roller support plate is a sliding panel that is inserted from above and held on the fixed base, supporting a pair of left and right side rollers and an upper roller on a main side.

[0040] Furthermore, by utilizing a structure without a lower roller, the space formed on the roller support plate for the passage of tubular materials is made into a slit-like opening that faces downwards towards the roller support plate. This allows for roller changes without disassembling the mandrel, even when using an internal weld seam cutting device, further improving workability during roller changes. Similarly, by utilizing a structure without a lower roller, the left and right side rollers are designed as inclined rollers with their respective support shafts facing upwards and outwards. This reduces roller weight, prevents roller marks, and shortens the distance from the welding work coil to the welding point, achieving both miniaturization and weight reduction of the device while improving tube quality. Additionally, by reducing thrust, the bearings supporting the side rollers can be miniaturized and have a longer lifespan. Attached Figure Description

[0041] Figure 1 This is a front view of the extrusion device according to the first embodiment of the present invention, viewed from the upstream side of the line.

[0042] Figure 2 This is the rear view of the same extrusion device.

[0043] Figure 3 This is a side view of the same extrusion device.

[0044] Figure 4 This is a top view of the same extrusion device.

[0045] Figure 5This is a perspective view from the front side of the same extrusion device.

[0046] Figure 6 This is a perspective view from the front side of the same extrusion device, showing the open / closed state of the cover.

[0047] Figure 7 This is a perspective view from the front side of the same extrusion device, showing the state in which the roller support plate is discharged upwards.

[0048] Figure 8 This is an enlarged 3D view of the front side of the same roller support plate.

[0049] Figure 9 This is an enlarged perspective view of the back side of the same roller support plate.

[0050] Figure 10 This is an enlarged perspective view showing the back side of the extrusion roller unit according to the second embodiment of the present invention.

[0051] Figure 11 This is a front view of the extrusion device according to the third embodiment of the present invention, viewed from the upstream side of the line.

[0052] Figure 12 This is the rear view of the same extrusion device.

[0053] Figure 13 This is a side view of the same extrusion device.

[0054] Figure 14 This is a top view of the same extrusion device.

[0055] Figure 15 This is a perspective view from the front side of the same extrusion device.

[0056] Figure 16 This is the front view of the same extrusion device, showing the state in which the roller support plate is pulled upwards.

[0057] Figure 17 This is a perspective view from the front side of the same extrusion device, showing the state in which the roller support plate is pulled upwards.

[0058] Figure 18 This is an enlarged 3D view of the front side of the same roller support plate.

[0059] Figure 19 This is an enlarged perspective view of the back side of the same roller support plate.

[0060] Figure 20 This is a structural diagram of the mandrel mounted on the extrusion device; it is a schematic side view. Detailed Implementation

[0061] Hereinafter, embodiments of the present invention will be described in the order of the first embodiment, the second embodiment, and the third embodiment.

[0062] like Figures 1 to 7 As shown, the extrusion device of the first embodiment is an extrusion roller base disposed in the welding section of a resistance welded steel pipe manufacturing line. The extrusion device includes: a U-shaped fixed base 10 disposed in the welding section, through which the formed tubular material passes; and an extrusion roller unit detachably mounted inside the U-shaped fixed base 10.

[0063] The U-shaped fixing base 10 is a U-shape formed by a horizontal lower part 11A and two vertical side parts 11B. The U-shaped fixing base 10 is integrally mounted on the fixing base 20. The U-shaped fixing base 10 is equipped with an anti-detachment mechanism 30, which is used to fix the extrusion roller unit installed within the U-shaped fixing base 10. Here, the anti-detachment mechanism 30 is an opening / closing cover 39 for opening and closing the open upper part of the U-shaped fixing base 10. The opening / closing cover 39 is a component corresponding to the omitted horizontal upper part of the U-shaped fixing base 10. It is opened and closed by a hinge structure, which is constructed by rotatably supporting one end of the opening / closing cover 39 on a side part 11B by a support shaft 31. The opening / closing cover 39 is mechanically opened and closed by a cylinder 32 longitudinally mounted on the outer side of the same side part 11B, and is fixed in an open state (see reference). Figure 6 In addition, with the open upper part of the U-shaped fixing base 10 closed, the other end is locked by the locking mechanism 33 similarly provided on the upper surface of the other side 11B, thereby fixing it in the closed state.

[0064] like Figure 8 and Figure 9 As shown, the extrusion roller unit installed inside the U-shaped fixed base 10 is a three-roller structure composed of side rollers 40, 40 on both sides and a single upper roller 50, and includes a vertical, panel-shaped roller support plate 60 that supports these extrusion rollers on the front side. The roller support plate 60 is a sliding plate that is inserted into the inside of the U-shaped fixed base 10 by a crane while supporting the side rollers 40, 40 and the upper roller 50 on the front side, and then pulled upwards from that inside. Furthermore, in the inserted state, the roller support plate 60 is fixed in the vertical direction by an opening / closing cover 39 provided on the U-shaped fixed base 10. Additionally, as... Figure 7 As shown, the roller support plate 60 is fixed in the direction of pipeline production by means of the first locking part 34 installed on the back of the opening and closing cover 39, the pair of second locking parts 12A, 12A on the left and right sides of the upper surface of the lower side 11A of the U-shaped fixed base 10, and the third locking parts 12B, 12B which also serve as vertical sliding guides installed on the inner sides of the side parts 11B, 11B on both sides.

[0065] like Figure 2 and Figure 9 As shown, the roller support plate 60 has a space 61 for tubular material to pass through in the portion where it intersects with the tubular line, i.e., the portion surrounded by the side rollers 40, 40 and the upper roller 50. The space 61 is a through hole that is completely enclosed around its perimeter.

[0066] Among the rollers supported by the front side of the roller support plate 60, the side rollers 40, 40 are horizontal rollers rotatably supported on roller yokes 41 that open in both the front and inner directions via vertical support shafts 42. More specifically, the side rollers 40, 40 are unequal-diameter rollers with a lower flange diameter larger than the upper flange diameter, designed to support tubular materials from below. The roller yoke 41 is bolted to a sliding block 43 that engages with a guide hole 62 formed in the lateral length of the roller support plate 60. The sliding block 43 is elastically held outward by a pair of upper and lower reset mechanisms 44, 44 with built-in horizontal springs mounted on the back of the roller support plate 60. Thus, each side roller 40 can be detached from the roller support plate 60 and can move horizontally and press outward.

[0067] The upper roller 50 is a single vertical roller with an annular recess 51 in its center to avoid interference with the weld seam of the tubular material. The upper roller 50 is rotatably supported by a horizontal support shaft 53 on a roller yoke 52 that opens in both the front and lower directions. The roller yoke 52 is laterally slidably mounted on a sliding upper roller mounting plate 54 via a fixing member 59 that also serves as a guide, and its lateral position is adjusted by an adjusting screw (not shown). The upper roller mounting plate 54 is configured as a secondary panel on the front side of the roller support plate 60, which serves as the main panel. On the other hand, the upper roller mounting plate 54 is slidably supported in the vertical direction by vertical guides 55, 55 on both sides, and is elastically held upward by a reset mechanism 56, 56 with a built-in vertical spring mounted on the back of the roller support plate 60. Thus, the upper roller 50 can be detached from the roller support plate 60 and can move vertically and press upward.

[0068] Furthermore, a pair of first pressing devices 70A and 70A for the side rollers 40 and 40 on both sides are installed inward through the side portions 11B and 11B on both sides of the U-shaped fixed base 10, and a second pressing device 70B for the upper roller 50 is installed inward through the opening and closing cover 39 provided on the U-shaped fixed base 10.

[0069] The first pressing device 70A is driven by a motor 71A mounted together with it on the side portion 13B, thereby changing the stop position of the bracket 41 of the side roller 40 and adjusting the pressing amount of the side roller 40. The second pressing device 70B is driven by a motor 71B mounted together with it on the opening / closing cover 39, thereby changing the stop position of the bracket 52 of the upper roller 50 and adjusting the pressing amount of the upper roller 50. Here, the opening / closing cover 39 serves as the anti-detachment mechanism 30 for the roller support plate 60 in the extrusion roller unit, but also functions as the mounting base for the second pressing device 70B.

[0070] The extrusion device of the first embodiment constructed as described above is used and functions as follows.

[0071] This extrusion apparatus is positioned so that the front side faces the upstream side of the line. With the opening / closing cover 39, which serves as an anti-detachment mechanism 30, located on the U-shaped fixed base 10, in the open state, the roller support plate 60 is inserted into the U-shaped fixed base 10, thereby installing the side rollers 40, 40 and the upper roller 50 within the U-shaped fixed base 10. Next, the opening / closing cover 39 is fixed in the closed state. In this state, the tubular material with heated mating edges enters the extrusion apparatus from the front side, and the mating edges are pressed and welded by the side rollers 40, 40 and the upper roller 50 with a predetermined reduction amount.

[0072] At this time, the tubular material passes through the space 61 of the roller support plate 60. In the space 61, the mandrel for grinding the inner weld seam is installed inside the tubular material. In addition, the side rollers 40, 40 on both sides are pressed down by a predetermined amount to overcome the pressing force through the first pressing devices 70A, 70A on both sides, and the upper roller 50 is pressed down by a predetermined amount to overcome the pressing force through the second pressing device 70B installed on the opening and closing cover 39.

[0073] During roller changing, after the tubular material is pulled out of the extrusion device, the first pressing device 70A, 70B is released, and the second pressing device 70B is also released. As a result, the side rollers 40, 40 return to their initial outer positions, and the upper roller 50 returns to its initial upper position. Then, the opening / closing cover 39 on the U-shaped fixed base 10 is opened. After opening the upper part of the U-shaped fixed base 10, the roller support plate 60 is lifted by a crane, and the side rollers 40, 40 and the upper roller 50, along with the roller support plate 60, are removed to the outside of the U-shaped fixed base 10.

[0074] At this time, since the side rollers 40, 40 and the upper roller 50, which serve as the two sides of the extrusion roller, are supported on the upstream side of the roller support plate 60, the roller support plate 60 is located on the downstream side of the extrusion roller. Therefore, when the mandrel is used exclusively for the impedance device, since its front end only reaches the extrusion roller, there is no interference between the roller support plate 60 and the mandrel, and the mandrel does not need to be disassembled. When the mandrel is used for the impedance device and the inner surface weld grinding device, the mandrel is removed from the support bracket and pulled out from the space 61 of the roller support plate 60, and then the roller support plate 60 is lifted. Then, the roller support plates 60 supporting the other side rollers 40, 40 and the upper roller 50 are lifted by a crane and installed in the U-shaped fixed base 10. Therefore, all the rollers of the extrusion roller base are replaced simply by lifting and lowering the roller support plates 60 by a crane.

[0075] After the roller support plate 60 is installed inside the U-shaped fixed base 10, the opening and closing cover 39 installed on the U-shaped fixed base 10 is fixed in the closed state. The roller support plate 60 is then firmly fixed to the inside of the fixed base 10 by the third locking part 34 installed on the back of the opening and closing cover 39, the second locking parts 12B, 12B installed on the inner sides of the side parts 11B, 11B on both sides and serving as vertical sliding guides, and the pair of left and right first locking parts 12A, 12A installed on the upper surface of the lower side part 11A.

[0076] After being removed from the roller support plate 60 outside the U-shaped fixed base 10, the side rollers 40, 40, together with the brackets 41, 41 and the sliding blocks 43, 43, are detached from the roller support plate 60 by loosening the bolts. Additionally, the upper roller 50 is detached from the sliding upper roller mounting plate 54 along with the bracket 52. As a result, it is easy to replace the other side rollers 40, 40 and the upper roller 50. Since the first pressing device 77A, 70A and the second pressing device 70B provided on the U-shaped fixed base 10 can freely adjust the pressing amount, they can be used regardless of the type of side rollers 40, 40 and the upper roller 50.

[0077] Thus, changing the side rollers 40, 40 and the upper roller 50 of the extrusion device in the first embodiment is extremely easy. The extrusion roller is a three-roller structure of side rollers 40, 40 and upper roller 50, so the device structure is simple. Since the roller support plate 60 supporting the extrusion roller on the front side is firmly supported on the inside of the U-shaped fixed base 10 in conjunction with the opening and closing cover 39, a clamping mechanism for fixing is not required, which also contributes to the simplification of the device structure.

[0078] Next, the second embodiment of the present invention will be described. For example... Figure 10As shown, the extrusion apparatus of the second embodiment differs from that of the extrusion apparatus of the first embodiment in that the shape of the roller support plate 60 is different. More specifically, the space 61 through which the tubular material passes is changed from a closed through hole to a portion of a downwardly opening slit-like opening. Other structures are substantially the same as those of the extrusion apparatus of the first embodiment, and the same reference numerals are used for the same parts, with descriptions omitted.

[0079] That is, in the extrusion apparatus of the second embodiment, the space 61 in the roller support plate 60 for the tubular material to pass through is part of a downwardly opening slit-like portion (here, the upper portion). Similar to the extrusion apparatus of the first embodiment, the extrusion roller consists of side rollers 40, 40 on both sides and an upper roller 50, omitting the lower roller. Therefore, when changing rollers, not only the mandrel for the impedance device, but also the mandrel for the impedance device and the inner weld grinding device installed in the space 51 does not need to be disassembled. Thus, the roller changing operation becomes simpler.

[0080] In both the extrusion apparatus of the first embodiment and the extrusion apparatus of the second embodiment, the lower roller, which serves as the extrusion roller, is omitted. However, since the side rollers 40, 40 on both sides are rollers with different diameters, the tubular material is supported from the bottom.

[0081] Next, the third embodiment of the present invention will be described. The extrusion device of the third embodiment differs from the extrusion device of the first embodiment and the extrusion device of the second embodiment in that the side rollers 40, 40 and the upper roller 50 on both sides of the extrusion roller, the roller support plate 60 supporting them, the anti-detachment mechanism 30 that fixes the roller support plate 60 in the U-shaped fixed base 10 in the vertical direction, and the second pressing device 70B that presses down the upper roller 50.

[0082] The structure of the extrusion device according to the third embodiment will be described in detail below. Figures 11-17 As shown, the extrusion device includes the same U-shaped fixed base 10 as described above and an extrusion roller unit detachably mounted inside the U-shaped fixed base 10. The extrusion roller unit is a four-roller structure consisting of side rollers 40, 40 on both sides and split upper rollers 50, 50 that press the two edges of the tubular material from an oblique upward position. These extrusion rollers are supported on the front side of a vertical, panel-shaped, sliding roller support plate 60. By hoisting with a crane, these extrusion rollers, together with the roller support plate 60, are inserted into the U-shaped fixed base 10 and pulled upward from the inside of the U-shaped fixed base 10.

[0083] The side rollers 40 and 40 are supported on the front side of the roller support plate 60. The side rollers 40 and 40 are equal-diameter rollers with the same upper and lower outer diameters, and are rotatably supported on the roller yokes 41 and 41 on both sides by support shafts 42 and 42 that are inclined upward and outward. That is, the side rollers 40 and 40 are inclined rollers with their respective support shafts 42 and 42 inclined upward and outward.

[0084] like Figure 18 and Figure 19 As shown, the yoke 41 of the side roller 40 is bolted to a sliding block 43 that engages with a guide hole 62 formed in the roller support plate 60 with a transverse length. The sliding block 43 is elastically held outward by a pair of upper and lower reset mechanisms 44, 44 with built-in horizontal springs mounted on the back of the roller support plate 60. Thus, each side roller 40 can be detached relative to the roller support plate 60 and can move in the horizontal direction and press outward.

[0085] The segmented upper rollers 50 and 50 are inclined rollers whose respective support shafts 53 and 53 are inclined outward relative to the horizontal line. Their respective roller yokes 52 and 52 are detachably mounted on a sliding upper roller mounting plate 54, which is configured as a secondary panel on the upper front side of the roller support plate 60, which serves as the main panel. The upper roller mounting plate 54 is slidably supported by vertical guides 55 and 55 on both sides and is elastically held upward by a reset mechanism 56 with a built-in vertical spring mounted on the roller support plate 60. Thus, the upper rollers 50 and 50 can be detached relative to the roller yokes 52 and 52, and the roller yokes 52 and 52 can move relative to the upper roller mounting plate 54 and press upward.

[0086] The roller support plates 60 supporting these roller groups are fixed within the U-shaped fixed base 10 by clamping mechanisms 35, 35 installed on the upper surfaces of the two sides 11B, 11B. The clamping mechanisms 35, 35 constitute the anti-detachment mechanism 30 of the roller support plates 60. They push the stop members inward by horizontally inward cylinders 36, and the stop members engage with the conical bearing portion 37 installed on the front side of the roller support plates 60, thereby pressing and fixing the roller support plates 60 downward.

[0087] The roller support plate 60, like the extrusion device of other embodiments, has a space 61 at the bottom for tubular material to pass through. This space 61, like the extrusion device of the second embodiment, is part of a downwardly opening slit-like opening (in this case, the upper part).

[0088] On the other hand, as mentioned above, the sliding upper roller mounting plate 54, which is configured as a sub-panel on the front side of the roller support plate 60, can move vertically and press upward. Meanwhile, it is pressed downward and fixed by a horizontally positioned wedge-shaped slider 67 located on the uppermost front side of the roller support plate 60. Specifically, the horizontally positioned wedge-shaped slider 67 can move along a horizontal guide 68 mounted on the uppermost front side of the roller support plate 60. The wedge-shaped slider 67 is elastically held in its initial outer position by a horizontally positioned spring-loaded reset mechanism 69 mounted on the back side of the roller support plate 60. It is then forcibly pressed inward by a second pressing device 70B, consisting of a horizontally positioned jack mounted on one of the clamping mechanisms 35, thereby overcoming the force that presses the upper roller mounting plate 54 upward and pressing downward, thus pressing down the segmented upper rollers 50, 50.

[0089] The upper rollers 50 and 50 are respectively combined with jacks 79 and 79 that adjust the pressing position. Each jack 79 is mounted on the front side of the upper roller mounting plate 54 together with the upper roller 50 in order to directly press down the roller yoke 52 of the upper roller 50. Each jack 79 is driven by a drive mechanism 72 provided from the back of the roller support plate 60 to the back of the U-shaped fixed base 10.

[0090] like Figure 12 As clearly shown, each drive mechanism 72 is configured to transmit the rotational force of a motor 73 mounted on the back of the U-shaped fixed base 10 to a vertically upward output shaft 74 also mounted on the back of the U-shaped fixed base 10, and to transmit the rotation of the output shaft 74 to a rotation transmission shaft 75 vertically mounted on the lower back of the roller support plate 60. The rotation transmission shaft 75 is a double structure in which a main rotating shaft (first rotating shaft) is inserted into a fixed sleeve. With the roller support plate 60 mounted within the U-shaped fixed base 10, the main rotating shaft (first rotating shaft) is located directly above the output shaft 74 and is fitted and connected to the upper part of the output shaft 74. The rotation of the main rotating shaft (first rotating shaft) is transmitted to a second rotating shaft 76 slidably connected to the upper part of the main rotating shaft (first rotating shaft), and then transmitted via a steering gear 77 to the jack 79 disposed on the front side of the upper roller mounting plate 54.

[0091] Thus, the jack 79 for adjusting the pressing position, located on the front side of the upper roller mounting plate 54, is driven by the rotation of the motor 73 mounted on the back of the U-shaped fixed base 10. The pulling of the roller support plate 60 from the U-shaped fixed base 10 is achieved by separating the rotation transmission shaft 75 from the output shaft 74. Furthermore, the up-and-down movement of the upper roller mounting plate 54 relative to the roller support plate 60 is absorbed by the axial sliding operation of the second rotation shaft 76.

[0092] On the other hand, the first pressing devices 70A and 70A for pressing down the side rollers 40 and 40 on both sides are the same as the extrusion devices of the first embodiment and the second embodiment described above. They are motor-driven jacks installed on the outer surfaces of the side portions 11B and 11B on both sides of the U-shaped fixed base 10. Other structures are also substantially the same as the extrusion devices of the first embodiment and the second embodiment.

[0093] The extrusion device of the third embodiment constructed as described above is used and functions as follows.

[0094] This extrusion apparatus, like the extrusion apparatus of the first embodiment and the extrusion apparatus of the second embodiment, has its front side facing the upstream side of the line. Moreover, with the clamping mechanisms 34, 34 provided on both sides 11B, 11B of the U-shaped fixed base 10 open to both sides, by inserting the roller support plate 60 into the U-shaped fixed base 10 and driving the clamping mechanisms 34, 34 to the closed position inward, the side rollers 40, 40 on both sides and the segmented upper rollers 50, 50 on both sides are installed in the U-shaped fixed base 10.

[0095] Furthermore, the wedge-shaped slider 67 is forcibly pressed inward by the second pressing device 70B, which is composed of a horizontally oriented cylinder. This causes the upper roller mounting plate 54 to be pressed downward against the upward pressing force, setting a predetermined pressing amount for the segmented upper rollers 50, 50. At this time, the pressing amount of the upper rollers 50, 50 is finely adjusted by the pressing position adjustment jacks 79, 79 combined with the upper rollers 50, 50, thereby adjusting the edge joining and overlap of the tubular material. Additionally, the side rollers 40, 40 are set with a predetermined pressing amount by overcoming the pressing force using the first pressing devices 70A, 70A on both sides.

[0096] Then, in this state, the tubular material with heated edges enters the extrusion device from the front side. The two edges are pressed and welded by the side rollers 40, 40 on both sides and the segmented upper rollers 50, 50 with a specified reduction. At this time, the tubular material passes through the space 61 of the roller support plate 60. In the space 61, the mandrel for grinding the inner weld seam is installed in a position located inside the tubular material.

[0097] During roller changing, after the tubular material is pulled out of the extrusion device, the first pressing devices 70A and 70B are reset, and the second pressing device 70B is also reset. This returns the side rollers 40 and 40 to their initial outer positions, and the upper roller 50 to its initial upper position. Furthermore, the second pressing device 70B, which consists of horizontal jacks, is opened, causing the wedge-shaped slider 67 to automatically reset to its initial outer position. This automatically resets the upper roller mounting plate 54 to its initial upward position.

[0098] Then, the clamping mechanisms 34, 34 set on the U-shaped fixed base 10 are driven to open positions on both sides, and the roller support plate 60 is lifted by a crane and taken out together with the side rollers 40, 40 on both sides and the split upper rollers 50, 50 to the outside of the U-shaped fixed base 10.

[0099] At this time, since the space 61 in the roller support plate 60 through which the tubular material passes is the same as that in the extrusion device of the second embodiment, it is part of a downwardly opening slit-like opening (in this case, the upper part), and the extrusion roller is composed of side rollers 40, 40 on both sides and segmented upper rollers 50, 50, and the lower roller is omitted, it is not necessary to disassemble the impedance device and the mandrel used for the inner surface weld grinding device installed in the space 51 when changing the roller. Therefore, the roller changing operation can be performed more simply and quickly.

[0100] After the roller support plate 60 is installed inside the U-shaped fixed base 10, the clamping mechanisms 34, 34 installed on the U-shaped fixed base 10 are driven to the closed position inward, and the wedge slider 67 is driven to the fixed position inward, in preparation for the next tube making.

[0101] Thus, changing the side rollers 40, 40 and the upper roller 50 of the extrusion device in the third embodiment is extremely easy. Since the extrusion roller is a four-roller structure consisting of the side rollers 40, 40 and the upper rollers 50, 50, the device structure is simple. In addition, unlike the extrusion devices of the first and second embodiments, the device does not have an anti-detachment mechanism 30 as a roller support plate 60 to close the opening and closing cover 39 of the open upper part of the U-shaped fixed base 10, and the open upper part remains open, so the device is lighter in weight.

[0102] Regarding the side rollers 40, 40 on both sides, in the extrusion apparatus of the first embodiment and the extrusion apparatus of the second embodiment, in order to support the tubular material without the lower roller, rollers with a lower flange diameter larger than the upper flange diameter are used. As a result, the increase in roller weight, the generation of roller marks, the increase in distance from the welding working coil to the welding point, and consequently the increase in thrust become problems. However, in the extrusion apparatus of the third embodiment, since the side rollers 40, 40 on both sides are equal-diameter rollers with the same outer diameter for the upper flange and the lower flange, these problems are solved.

[0103] Furthermore, since the equal-diameter side rollers 40, 40 are constructed as inclined rollers with their respective support shafts 41, 41 pointing upwards and tilted outwards, the tubular material is effectively supported from below at an angle, even though they are equal-diameter rollers. The reason why inclined rollers can be used as side rollers 40, 40 is that there is no lower roller, and there is no interference with the lower roller.

[0104] The above describes three embodiments, but the present invention is applicable regardless of pipe size and is particularly effective for extrusion apparatuses for medium-diameter and large-diameter pipes that conventionally use five rollers. Specifically, of the three embodiments, the first embodiment is suitable for extrusion apparatuses for smaller small-diameter pipes (2-3 inches) that do not use an internal weld grinding device; the second embodiment is suitable for extrusion apparatuses for larger small-diameter pipes (3-4 inches); and the third embodiment is suitable for extrusion apparatuses for medium-diameter and large-diameter pipes of 5 inches and above.

[0105] Explanation of reference numerals in the attached figures

[0106] 10 U-shaped fixed base

[0107] 11A lower part

[0108] 11B Side

[0109] 12A Second Stop

[0110] 12B Third Stop

[0111] 20 Fixed base

[0112] 30 Anti-hair loss mechanism

[0113] 31 Support shaft

[0114] 32 cylinders

[0115] 33 Locking mechanisms

[0116] 34 First stop part

[0117] 35 Clamping mechanism (anti-detachment mechanism)

[0118] 36 cylinders

[0119] 37 Bearing section

[0120] 39. Opening and closing cover (anti-detachment mechanism)

[0121] 40 side rollers

[0122] 41 Roller Yoke

[0123] 42 Support Shaft

[0124] 43 Slider

[0125] 44 Reset Mechanism

[0126] 50 upper roller

[0127] 51. Annular recess

[0128] 52 Roller Yoke

[0129] 53 Support shaft

[0130] 54 Upper roller mounting plate (sub-panel)

[0131] 55 Vertical guide

[0132] 56 Reset Mechanism

[0133] 59 Fasteners

[0134] 60-roll support plate (main panel)

[0135] 61 Space

[0136] 62 guide hole

[0137] 67 Wedge slider

[0138] 68 Horizontal guide

[0139] 69 Reset Mechanism

[0140] 70A First Pressing Device

[0141] 71A motor

[0142] 70B Second Pressing Device

[0143] 71B electric motor

[0144] 72 Drive mechanism

[0145] 73 Electric motor

[0146] 74 Output shaft

[0147] 75 Rotary transmission shaft

[0148] 76 Second Rotation Axis

[0149] 77 Steering Gear

[0150] 79. Jack for adjusting the position.

Claims

1. An extrusion device disposed on a resistance welded pipe manufacturing line, wherein an impedance support mandrel is inserted and fixed within the tubular material on the pipe manufacturing line, extending from the upstream side of the line at least to the extrusion roller. The extrusion device includes: A U-shaped fixing base, the inner side of which allows the tubular material to pass through, and the upper part is open; The roller support plate is composed of a sliding panel that is inserted into and held within the U-shaped fixed base from the open upper part of the U-shaped fixed base; The extrusion roller is mounted on the main surface of the upstream side of the roller support plate and consists of an upper roller and left and right side rollers; A first pressing device and a second pressing device are disposed on the U-shaped fixed base. With the roller support plate fixed within the base, the first pressing device presses the left and right side rollers inward, and the second pressing device presses the upper roller downward; and An anti-detachment mechanism is used to fix the roller support plate inserted into the U-shaped fixed base within the U-shaped fixed base. The upper roller is either a single-roller structure that presses the mating edge of the tubular material from directly above, or a two-roller structure that presses the mating edge from obliquely above. The left and right side rollers each have a roller shaft, which is either a vertical shaft or an inclined shaft that faces upward and tilts outward. The roller support plate has a space formed in a position surrounded by the side rollers and the upper roller for the tubular material to pass through, and no roller is provided in a position to support the tubular material from below. This allows the extrusion roller to be replaced without moving the impedance support mandrel inside the tubular material, by pulling the roller support plate upwards from the open upper part of the U-shaped fixed base.

2. The extrusion device according to claim 1, wherein, The space for tubular material to pass through in the roller support plate is part of a slit-like opening that opens downward toward the bottom of the roller support plate.

3. The extrusion device according to claim 1, wherein, The left and right side rollers are inclined rollers whose respective roller shafts face upwards and tilt outwards.

4. The extrusion device according to claim 1, wherein, The anti-detachment mechanism is an openable and closable cover that can be opened and closed in the open upper part of the U-shaped fixing base.

5. The extrusion device according to claim 4, wherein, The opening and closing cover also serves as the mounting base for the second pressing device.

6. The extrusion device according to claim 1, wherein, The anti-detachment mechanism is a pair of left and right clamping mechanisms, which are respectively installed on both sides of the U-shaped fixed base and respectively engaged with the side edges of the roller support plate inserted into the U-shaped fixed base.

7. The extrusion apparatus according to claim 6, wherein, The second pressing device is a combination of the pressing device body and the driving mechanism of the body. The pressing device body is mounted on a sliding upper roller mounting plate that can be raised and lowered along one main surface of the roller support plate. The driving mechanism of the body is constructed on the other side of the roller support plate or on the other side from the roller support plate to the U-shaped fixed base.

Images