A device for forming a tunnel tube and a method for calibrating the same

Abstract

The present application relates to the technical field of tunnel pipe forming, in particular to a device for tunnel pipe forming and a calibration method thereof. The device comprises a supporting mechanism, a former body and a lubricating mechanism. The former body is detachably installed at the top end of the supporting mechanism and has a hollow cylindrical structure. A plurality of lubricating mechanisms are detachably installed on the former body, with one end of each lubricating mechanism protruding from the inner wall of the cylindrical structure of the former body. The cylindrical structure of the former body is used to accommodate and form a workpiece. During the forming process of the workpiece, the end of the lubricating mechanism protruding from the inner wall of the cylindrical structure of the former body is in sliding cooperation with the outer wall of the workpiece in the cylindrical structure of the former body. The present application can greatly reduce the wear of the inner wall of the former body by the workpiece, reduce the friction between the workpiece and the inner wall of the former body, improve the production efficiency and reduce the driving cost.

Description

[0001] Cross-references to related applications This application is a divisional application of the invention entitled “A Tunnel Tube Forming Device and Calibration Method Thereof”, filed on March 4, 2025, with application number “CN202510251235.6”, which is incorporated herein by reference in its entirety. Technical Field

[0002] This invention relates to the field of tunnel tube forming technology, and in particular to a device for tunnel tube forming and its calibration method. Background Technology

[0003] A rocket tunnel tube is a testing device used to simulate the working environment of a rocket engine. It can generate high temperature, high pressure and high speed airflow under controlled conditions to verify the engine's performance and reliability.

[0004] The manufacturing of rocket tunnel tubes is inseparable from their welding equipment. This equipment is used specifically for manufacturing rocket tunnel tubes. Existing rocket tunnel tube welding equipment mainly consists of a control system, a gas protection device, a welding system, a dust removal fan, and a forming device. Among these, the forming device is a key component, ensuring precise forming and dimensional control of the tube (workpiece) during the welding process. During welding, the tube enters the forming device and fits tightly against its inner wall, forming a pipe within the device. The forming device also ensures the diameter accuracy of the formed pipe, thereby guaranteeing a good fit between the seams of the two pipes to be welded in subsequent welding processes, meeting the requirements of subsequent welding.

[0005] However, several problems still exist when using large-diameter, thin-walled tubing for spiral forming within the forming unit. First, large-diameter tubing is typically made of high-strength stainless steel, which has considerable hardness. When tightly fitted against the inner wall of the forming unit, it causes significant wear, compromising the dimensional accuracy and surface quality of the product. Second, the tight fit of the tubing against the inner wall creates sliding friction, which generates substantial resistance. This increases the driving force required to move the tubing within the forming unit, reducing production efficiency and driving costs.

[0006] Currently, to address these issues, lubricant is typically added to the inner wall of the forming machine to reduce wear and friction between the pipe and the forming machine's inner wall. However, this method is not ideal, as the lubricant contains many impurities. When the pipe enters the forming machine, its surface and weld seams become contaminated with this impurity-laden lubricant. Before subsequent welding, the lubricant on the pipe surface and at the weld seams needs to be removed, thus reducing production efficiency and increasing additional labor costs.

[0007] Therefore, how to reduce wear on the inner wall of the forming device, while also reducing the friction between the pipe and the inner wall of the forming device, thereby improving production efficiency and reducing drive costs, has become an urgent problem to be solved. Summary of the Invention

[0008] The purpose of this invention is to provide a device for tunnel pipe forming and a calibration method thereof, so as to solve the problems existing in the prior art.

[0009] To achieve the above objectives, the present invention provides the following solution: A first aspect of the present invention provides an apparatus for forming tunnel pipes, comprising a support mechanism, a forming device body, and a lubrication mechanism, wherein: The molding body is detachably mounted on the top of the support mechanism, and the molding body is a hollow cylindrical structure. Several lubrication mechanisms are detachably installed on the molding body, with one end of each lubrication mechanism protruding from the inner wall of the cylindrical structure of the molding body. The cylindrical structure of the forming device body is used to accommodate and form the workpiece. During the forming process of the workpiece, the end of the lubrication mechanism protruding from the inner wall of the cylindrical structure of the forming device body slides and engages with the outer wall of the workpiece within the cylindrical structure of the forming device body.

[0010] According to one embodiment of the present invention, the molding body has a spiral structure.

[0011] According to one embodiment of the present invention, the support mechanism includes a base and a leg, the leg being detachably mounted on the top of the base, and the molding body being detachably mounted on the top of the leg.

[0012] According to one embodiment of the present invention, a pad is installed at the top of the base, the pad is disposed corresponding to the inlet of the molding body, and the thickness of the pad is the same as the wall thickness of the inlet of the molding body.

[0013] According to one embodiment of the present invention, the lubrication mechanism includes ball bearings, and the forming body has a plurality of mounting holes, wherein the plurality of ball bearings are respectively limited and installed in the plurality of mounting holes, and the ball bearings are slidably connected to the mounting holes; one end of the ball bearing away from the mounting hole it mates with protrudes from the inner wall of the cylindrical structure of the forming body and slidably engages with the outer wall of the workpiece.

[0014] According to one embodiment of the present invention, the lubrication mechanism further includes mounting blocks, and a plurality of mounting blocks are detachably mounted in a plurality of mounting holes; the ball bearings are slidably mounted on the mounting blocks and are slidably connected to the mounting blocks, and the ball bearings are connected to the mounting holes through the mounting blocks.

[0015] According to one embodiment of the present invention, the tunnel tube forming apparatus further includes a calibration cylinder for calibrating the lubrication mechanism on the forming body; the calibration cylinder is a hollow structure and located inside the cylindrical structure of the forming body, and the calibration cylinder is coaxially arranged with the forming body and clearance-fitted with the inner wall of the forming body; a plurality of calibration mechanisms are arranged circumferentially on the calibration cylinder, and one end of the calibration mechanism located outside the calibration cylinder is used to abut against the inner wall of the forming body.

[0016] According to one embodiment of the present invention, the calibration mechanism includes a calibration groove formed on the outer wall of the calibration cylinder, a calibration hole formed in the calibration groove, and a calibration bolt threaded in the calibration hole; when the calibration cylinder calibrates the lubrication mechanism on the molding body, one end of the calibration bolt located outside the calibration cylinder abuts against the inner wall of the molding body.

[0017] According to one embodiment of the present invention, a plurality of lifting holes are provided at one end of the calibration cylinder.

[0018] A second aspect of the present invention also provides a calibration method for a tunnel forming apparatus, comprising the step of calibrating the tunnel forming apparatus, which includes: S1. Place the molding machine body vertically; S2. Hoist the calibration cylinder into the cylindrical structure of the forming machine body; S3. Adjust the calibration cylinder and the forming device body to be in a coaxial position; S4. Install the calibration bolt from inside the calibration cylinder into the calibration hole until one end of the calibration bolt outside the calibration cylinder contacts the inner wall of the forming body. S5. Install the mounting block from the outside of the molding machine body into the mounting hole until the ball bearings on the mounting block contact the outer wall of the calibration cylinder. S6. Lift the calibration cylinder out of the cylindrical structure of the forming machine body.

[0019] This invention has at least the following technical effects: This invention provides a device and calibration method for tunnel tube forming. Through the inclusion of a lubrication mechanism, this invention significantly reduces wear on the inner wall of the forming unit during tunnel tube forming, as well as the friction between the workpiece and the inner wall of the forming unit. This improves production efficiency and reduces drive costs. Furthermore, the lubrication mechanism eliminates the need to add lubricant inside the forming unit, thus avoiding the need to treat lubricant contamination on the surface and weld seams of the tunnel tubes formed later. This reduces additional labor costs and further improves production efficiency. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 for Figure 1 A magnified view of a section at point A in the middle; Figure 3 for Figure 1 Overall structural diagram from other angles; Figure 4 This is a schematic diagram of the overall structure of the calibration cylinder in this invention; Figure 5 for Figure 4 A magnified view of a section at point B in the middle; Figure 6 for Figure 4 Overall structural diagram from other angles; Figure 7 for Figure 6 A magnified view of a section at point C; Figure 8 This is a schematic diagram of the overall structure of the workpiece located within the forming device body in this invention; Figure 9 This is a schematic diagram of the overall structure of the calibration cylinder and the forming device body installed horizontally in this invention; Figure 10 This is a side-front view schematic diagram of the overall structure of the lubrication mechanism in this invention; Figure 11 This is a side-rear view of the overall structure of the lubrication mechanism in this invention; Figure 12 This is a schematic diagram of the overall structure of the calibration cylinder and the forming device body installed vertically in this invention; The components are as follows: 1. Base; 2. Support leg; 3. Forming device body; 4. Pad block; 5. Front protective gas device connecting block; 6. Welding torch connecting block; 7. Back protective gas device connecting block; 8. Calibration cylinder; 9. Lifting hole; 10. Calibration groove; 11. Mounting block; 12. Ball bearing; 13. Workpiece; 14. Calibration bolt. Detailed Implementation

[0022] The features and exemplary embodiments of various aspects of the present invention will now be described in detail. To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only configured to explain the present invention and to exemplify the principles of the present invention, and are not configured to limit the present invention. In addition, the structural components in the drawings are not necessarily drawn to scale. For example, the dimensions of some structural components or regions in the drawings may be enlarged for other structural components or regions to aid in the understanding of the embodiments of the present invention.

[0023] The directional terms used in the following description refer to the directions shown in the figures and are not intended to limit the specific structure of the embodiments of the present invention. In the description of the present invention, it should be noted that, unless otherwise stated, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0024] Furthermore, the terms "comprising," "including," "having," or any other variations thereof are intended to cover non-exclusive inclusion, such that a structure or component that includes a list of elements includes not only those elements but also other structural elements that are not expressly listed or inherent to the structure or component. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the article or apparatus that includes the element.

[0025] Spatial relation terms such as "below," "under," "under," "low," "above," "on," and "high" are used for descriptive convenience to explain the positioning of one element relative to a second element, indicating that these terms are intended to cover different orientations of the device, in addition to those different from those shown in the figure. Furthermore, phrases such as "one element on / below another element" can indicate that two elements are in direct contact, or that there are other elements between the two elements. In addition, terms such as "first" and "second" are also used to describe individual elements, areas, parts, etc., without specifically indicating order or sequence, and should not be considered restrictive. Similar terms are used throughout the description to represent similar elements.

[0026] It will be apparent to those skilled in the art that the present invention can be practiced without requiring some of these specific details. The following description of embodiments is merely intended to provide a better understanding of the invention by illustrating examples of the invention.

[0027] Example 1 This invention provides a device for forming tunnel pipes, comprising a support mechanism, a forming body 3, and a lubrication mechanism, wherein: The molding body 3 is detachably installed on the top of the support mechanism. The molding body 3 is a hollow cylindrical structure. Preferably, the molding body 3 is a spiral structure. The inner wall dimension accuracy of the molding body 3 can be ±0.1mm, the shape accuracy can be 0.02mm, and the straightness can be 0.01mm.

[0028] In this embodiment, refer to Figure 1 or Figure 3 The forming body 3 can be detachably mounted on top of the support mechanism in a manner known to those skilled in the art, such as by means of bolt connection.

[0029] Several lubrication mechanisms are detachably installed on the molding body 3. One end of the lubrication mechanism is located inside the cylindrical structure of the molding body 3, that is, at least one end of the lubrication mechanism is located inside the cylindrical structure of the molding body 3 (i.e. protruding from the inner wall of the molding body 3) to achieve relative sliding cooperation with the outer wall of the workpiece 13 and to produce a lubrication effect on the workpiece 13.

[0030] Reference Figure 8 The cylindrical structure of the forming body 3 is used to accommodate and form the workpiece 13. During the forming process of the workpiece 13, the lubrication mechanism located at one end of the cylindrical structure of the forming body 3 (i.e., the end of the lubrication mechanism protruding from the inner wall of the forming body 3) slides with the outer wall of the workpiece 13 within the cylindrical structure of the forming body 3. The forming body 3 can be used to form the workpiece 13 into a tunnel tube.

[0031] In this embodiment, workpiece 13 can be a stainless steel plate made of a material known to those skilled in the art.

[0032] When it is necessary to use the tunnel tube forming apparatus of the present invention to produce tunnel tubes, firstly, the stainless steel sheet workpiece 13 is placed at the entrance of the forming body 3, and the workpiece 13 is made to fit tightly with the lubrication mechanism on the inner wall of the forming body 3.

[0033] Then, using external driving force, the workpiece 13 is pushed inward towards the interior of the molding body 3. At this time, the workpiece 13 will slide on the inner wall of the spiral-shaped molding body 3, spiraling inward (see reference). Figure 8 The plate-shaped workpiece 13 will be bent into a spiral structure by the inner wall of the forming body 3, thereby completing the production of the tunnel tube.

[0034] When the workpiece 13 slides on the inner wall of the forming body 3 and is squeezed by the inner wall of the forming body 3, the lubrication mechanism reduces the friction between the workpiece 13 and the inner wall of the forming body 3, thereby reducing the wear of the workpiece 13 on the inner wall of the forming body 3. At the same time, the reduction of friction can also reduce the external driving force, thereby reducing the driving cost and improving production efficiency.

[0035] Furthermore, the tunnel tube forming apparatus of the present invention, through the provision of a lubrication mechanism, can reduce the friction between the workpiece 13 and the inner wall of the forming body 3, eliminating the need to add lubricant to the inner wall of the forming body 3 to reduce friction, thus preventing lubricant contamination of the surface of the workpiece 13 and the weld seam. Therefore, before welding the tunnel tube formed from the workpiece 13, it is not necessary to remove the lubricant from the surface of the workpiece 13 (i.e., the formed tunnel tube) and the weld seam, thereby further improving production efficiency and reducing the labor cost of additional lubricant removal.

[0036] In addition, compared with existing forming machines, the tunnel pipe forming apparatus of the present invention requires less equipment investment, produces higher quality tunnel pipe products, and has a simpler manufacturing process.

[0037] According to one embodiment of the present invention, the support mechanism includes a base 1 and a leg 2, the leg 2 being detachably mounted on the top of the base 1, and the forming body 3 being detachably mounted on the top of the leg 2. The base 1 and the leg 2 can be made of stainless steel, a material known to those skilled in the art.

[0038] In this embodiment, refer to Figure 1 or Figure 3 The number of support legs 2 is preferably two, and they are located on both sides of the molding body 3 and arranged sequentially. The shape of the support legs 2 can be a U-shaped structure, and reinforcing ribs can be provided between the bottom plate and the side plate of the U-shaped structure, thereby increasing the strength of the support legs 2 and thus increasing the strength of the support for the molding body 3.

[0039] The bottom plate of the support leg 2 can be mounted on top of the base 1 in a manner known to those skilled in the art, such as by a detachable connection via bolts. The forming body 3 can be mounted on top of the support leg 2 in a manner known to those skilled in the art, such as by a detachable connection via bolts.

[0040] In addition, refer to Figure 3The base 1 can be a hollow structure, which can reduce the weight of the base 1, increase the portability of the base 1, and reduce the amount of material used in the production of the base 1, thus achieving an environmental protection effect and reducing costs.

[0041] According to one embodiment of the present invention, a pad 4 is installed at the top of the base 1, and the pad 4 is correspondingly disposed at the inlet of the molding body 3. The thickness of the pad 4 is the same as the wall thickness at the inlet of the molding body 3. The pad 4 can be made of stainless steel material known to those skilled in the art.

[0042] In this embodiment, refer to Figure 3 The pad 4 can be a cuboid structure and is located at the entrance of the spiral-shaped forming body 3. When the forming body 3 is used to form a tunnel tube for the workpiece 13, the pad 4 can support the workpiece 13 at the entrance of the forming body 3, thereby ensuring the relative flatness of the entrance of the forming body 3. This allows the workpiece 13 to enter the forming body 3 more smoothly and is not affected by the thickness of the forming body 3, further ensuring the smooth progress of the tunnel tube forming operation.

[0043] According to one embodiment of the present invention, referring to Figure 10 and Figure 11 The lubrication mechanism includes ball bearings 12, which can be made of stainless steel. The forming body 3 has several mounting holes, and the ball bearings 12 are respectively and slidably connected to these mounting holes. (See reference...) Figure 2 One end of the ball bearing 12 is located at least within the cylindrical structure of the forming body 3, and the end of the ball bearing 12 located within the cylindrical structure of the forming body 3 (i.e., the end of the ball bearing 12 furthest from its mating mounting hole) protrudes from the inner wall of the forming body 3 and slides against the outer wall of the workpiece 13, with a protrusion height of 1 mm. Furthermore, the lubrication mechanism also includes mounting blocks 11, several of which are detachably mounted in several mounting holes. The ball bearing 12 is slidably mounted on the mounting blocks 11 and is slidably connected to the mounting blocks 11, with the ball bearing 12 connected to the mounting holes via the mounting blocks 11. When the mounting blocks 11 are installed in the mounting holes, the end of the ball bearing 12 located within the cylindrical structure of the forming body 3 also protrudes from the inner wall of the forming body 3 to achieve a relative sliding fit with the outer wall of the workpiece 13.

[0044] In this embodiment, refer to Figure 10 and Figure 11 The diameter of the mounting hole can be 12mm. (Refer to...) Figure 1 , Figure 3 or Figure 9The number of mounting holes can be 300-400, and they are evenly arranged along the circumference of the molding body 3. Preferably, the mounting holes are arranged horizontally and vertically on the molding body 3, that is, several rows in the horizontal direction (along the axial direction of the molding body 3) and several columns in the vertical direction (along the circumferential direction of the molding body 3).

[0045] The mounting block 11 can be a cylindrical structure, with one end being a frustum structure, on which the ball bearing 12 is mounted and slidably positioned. The detachable connection between the mounting block 11 and the mounting hole can be a threaded connection as known in the art. Specifically, the outer wall of the mounting block 11 is provided with threads (not shown in the figure), and the wall of the mounting hole is provided with threads corresponding to those on the outer wall of the mounting block 11, thereby allowing the mounting block 11 to be installed in the mounting hole via a threaded connection.

[0046] Furthermore, when the mounting block 11 is installed in the mounting hole, there can be a certain amount of friction between the threads on the outer wall of the mounting block 11 and the threads on the wall of the mounting hole. For example, this friction can be achieved by placing an anti-slip material known in the art between them.

[0047] When the workpiece 13 is tunneled within the cylindrical structure of the forming body 3, the end of the ball bearing 12 located within the cylindrical structure of the forming body 3 (i.e., the end of the ball bearing 12 furthest from its mating mounting hole) protrudes from the inner wall of the forming body 3. Therefore, the ball bearing 12 can change the friction between the workpiece 13 and the inner wall of the forming body 3 from sliding friction to rolling friction, thereby greatly reducing the friction between the two. This reduces the wear of the workpiece 13 on the inner wall of the forming body 3, reduces the external driving force and driving cost, and increases production efficiency.

[0048] When the workpiece 13 is forming a tunnel tube within the cylindrical structure of the forming body 3, i.e., when the workpiece 13 is tightly fitted onto the ball bearings 12 on the mounting block 11 and moving, the mounting block 11 may become loose within the mounting hole under the pressure of the workpiece 13. This could lead to the ball bearings 12 falling below the height of the inner wall of the forming body 3, or even the mounting block 11 falling out of the mounting hole. However, in one embodiment of the present invention, by creating a certain friction between the threads on the outer wall of the mounting block 11 and the threads on the wall of the mounting hole, the friction between the two can prevent the mounting block 11 from becoming loose within the mounting hole, thereby ensuring the smooth progress of the tunnel tube forming process.

[0049] Furthermore, since the ball bearing 12 is located inside the cylindrical structure of the forming body 3 and protrudes from the inner wall of the forming body 3 at one end, and the number of ball bearing 12 is 300-400 and they are evenly arranged on the forming body 3, when the workpiece 13 is in contact with the inner wall of the forming body 3 to form a tunnel tube, the large number of ball bearing 12 can greatly reduce the direct contact between the workpiece 13 and the inner wall of the forming body 3, and can even directly avoid the workpiece 13 from directly contacting the inner wall of the forming body 3. That is, the workpiece 13 will have very little friction with the inner wall of the forming body 3, or even no friction at all, thereby further reducing the wear of the workpiece 13 on the inner wall of the forming body 3.

[0050] In addition, those skilled in the art can adjust the number of mounting holes on the forming body 3 according to the actual situation, and can also adjust the diameter and material of the ball 12 according to the actual situation. This can better adapt to workpieces 13 of different diameters or different materials, and can also prevent scratches or adhesion to the surface of workpieces 13 of different diameters or different materials.

[0051] According to one embodiment of the present invention, referring to Figure 4 or Figure 6 The tunnel tube forming apparatus further includes a calibration cylinder 8, which is used to calibrate the lubrication mechanism on the forming device body 3. The calibration cylinder 8 is a hollow structure and is located inside the cylindrical structure of the forming device body 3 (see reference). Figure 9 The calibration cylinder 8 is coaxially arranged with the molding body 3 and has a clearance fit with the inner wall of the molding body 3, the width of which is preferably 1 mm. Several calibration mechanisms are arranged circumferentially on the calibration cylinder 8, and one end of each calibration mechanism located outside the calibration cylinder 8 is used to abut against the inner wall of the molding body 3. Further, referring to… Figure 5 or Figure 7 The calibration mechanism includes a calibration groove 10 on the outer wall of the calibration cylinder 8, a calibration hole in the calibration groove 10, and a calibration bolt 14 threaded in the calibration hole. When the calibration cylinder 8 calibrates the lubrication mechanism on the molding body 3, one end of the calibration bolt 14 located outside the calibration cylinder 8 abuts against the inner wall of the molding body 3.

[0052] In this embodiment, refer to Figure 6 The number of calibration mechanisms can be 6, and they are evenly arranged along the circumference of the calibration cylinder 8, that is, the number of calibration slots 10 can be 6, and they are evenly arranged along the circumference of the calibration cylinder 8. Preferably, the calibration slots 10 can be rectangular slots, and they are opened along the length of the calibration cylinder 8 (i.e., the axial direction of the calibration cylinder 8).

[0053] According to one embodiment of the present invention, in this embodiment, reference is made to... Figure 6The number of calibration holes can be several, preferably eight. For example, these eight calibration holes are arranged vertically along the length of the rectangular calibration groove 10, and each calibration hole is threaded with a calibration bolt 14.

[0054] Furthermore, a rigid buffer layer, such as hard rubber or other materials known in the art, can be installed at the end of the calibration bolt 14 located outside the calibration cylinder 8. When the end of the calibration bolt 14 located outside the calibration cylinder 8 contacts the inner wall of the molding body 3, the buffer layer can prevent the calibration bolt 14 from directly contacting the inner wall of the molding body 3. This is because the hardness of hard rubber is much lower than the material hardness of the molding body 3, thus effectively preventing the calibration bolt 14 from wearing down the inner wall of the molding body 3, further avoiding wear on the inner wall of the molding body 3.

[0055] According to one embodiment of the present invention, a plurality of lifting holes 9 are provided at one end of the calibration cylinder 8.

[0056] In this embodiment, refer to Figure 4 The number of lifting holes 9 can be two, and their shape can be a rectangle with rounded transitions at all four included corners. The two lifting holes 9 can be opened opposite each other on the top of the calibration cylinder 8, and the two lifting holes 9 are of equal size and located on the same horizontal plane. Alternatively, those skilled in the art can also open more than two lifting holes 9 on the top of the calibration cylinder 8 according to actual needs.

[0057] When it is necessary to lift the calibration cylinder 8, an external lifting device can be used to extend a hook into the lifting hole 9, thereby facilitating the lifting operation of the calibration cylinder 8. The external lifting device and the hook are existing technologies known to those skilled in the art, and will not be described in detail here.

[0058] According to one embodiment of the present invention, a front protective gas device connecting block 5, a welding torch connecting block 6 and a back protective gas device connecting block 7 are detachably installed on the outer wall of the forming body 3. A front protective gas device (not shown in the figure) is detachably installed on the front protective gas device connecting block 5, a back protective gas device (not shown in the figure) is detachably installed on the back protective gas device connecting block 7, and a welding torch (not shown in the figure) is detachably installed on the welding torch connecting block 6.

[0059] In this embodiment, refer to Figure 1The front protective gas device connecting block 5, the welding torch connecting block 6, and the rear protective gas device connecting block 7 can all be connected to the forming device body 3 in a manner known to those skilled in the art, such as being detachably mounted on the outer wall of the forming device body 3 by means of bolts. The front protective gas device connecting block 5 can be a 90° bent flange structure, and the welding torch connecting block 6 can be a U-shaped bent flange structure, as shown in the reference... Figure 1 The opening of the U-shaped welding torch connecting block 6 can face the forming body 3, and the back protective gas device connecting block 7 can be a cuboid structure.

[0060] When the workpiece 13 enters the forming body 3 in a spiral and gradually forms a tunnel tube, there will be a spiral weld seam on the side wall of the formed tunnel tube. Therefore, it is necessary to weld this weld seam to achieve the closure of the side wall of the tunnel tube and complete the initial production of the tunnel tube.

[0061] During use, the workpiece 13 gradually enters the cylindrical structure of the forming body 3 to form a tunnel tube, and gradually extends out of the outlet of the forming body 3. Specifically, before using the forming body 3 to form the tunnel tube of the workpiece 13, the welding torch can be installed on the welding torch connecting block 6 in advance, and the torch tip can be aligned with the weld seam of the side wall of the tunnel tube that will subsequently extend out of the outlet of the forming body 3. Then, the front protective gas device can be installed on the front protective gas device connecting block 5, and the back protective gas device can be installed on the back protective gas device connecting block 7. Finally, the air outlet of the front protective gas device is aligned with the front of the weld seam of the tunnel tube that will subsequently extend out of the outlet of the forming body 3, and the air outlet of the back protective gas device is aligned with the back of the weld seam of the tunnel tube that will subsequently extend out of the outlet of the forming body 3, thus completing the preparation work for welding.

[0062] Just as the tunnel pipe is about to extend from the outlet of the forming unit 3, the welding torch, the front shielding gas device, and the back shielding gas device are activated simultaneously. At this moment, the welding torch will butt weld the weld seam on the tunnel pipe, and the front and back shielding gas devices will provide shielding gas to the front and back of the weld seam simultaneously. This can effectively prevent oxidation of the metal surface at the weld seam, avoiding the formation of an oxide layer and related defects. It can also improve the weld seam formation, making the weld seam smooth and uniform. In addition, during the welding process of the tunnel pipe, the front and back shielding gas devices can also cool the welding area, reduce the heat impact, and thus prevent deformation and coarse grains at the weld seam, thereby ensuring the good and normal progress of the welding work.

[0063] During the welding process on the sidewall of the tunnel pipe, the workpiece 13 gradually enters the cylindrical structure of the forming device body 3 under external driving force. Therefore, the already formed tunnel pipe at the outlet of the forming device body 3 gradually extends out from the outlet, meaning the tunnel pipe is in a moving state. Since the workpiece 13 is spirally formed inside the cylindrical structure of the forming device body 3, the weld seam of the tunnel pipe remains at the same relative position at the outlet of the forming device body 3 due to the movement of the tunnel pipe. Therefore, during the welding process of the tunnel pipe, only the welding torch, the front shielding gas device, and the back shielding gas device need to be installed on the forming device body 3. There is no need to move the positions of the welding torch, the front shielding gas device, and the back shielding gas device during the welding process to complete the welding of the tunnel pipe, thus greatly reducing the labor cost of welding tunnel pipes.

[0064] The present invention also provides a calibration method for a tunnel forming apparatus, comprising the steps of calibrating the aforementioned tunnel forming apparatus, one embodiment of which includes: S1. The molding body 3 with the mounting holes is placed vertically.

[0065] S2. Using the hook on the external hoisting equipment, hook the hoisting hole 9 and hoist the calibration cylinder 8 vertically into the cylindrical structure of the forming body 3 in S1 (refer to...). Figure 9 or Figure 12 ).

[0066] S3. Use external measuring equipment to measure the positions of the calibration cylinder 8 and the molding body 3, and measure the coaxial position of the calibration cylinder 8 and the molding body 3 (i.e., the positions of the calibration cylinder 8 and the molding body 3 at the same center of their cross-sections). After the measurement is completed, continue to use external hoisting equipment to move the calibration cylinder 8 from S2 inside the molding body 3 to the measured position, thereby adjusting the calibration cylinder 8 to a coaxial position with the molding body 3 (refer to...). Figure 12 During the movement of the calibration cylinder 8, the calibration hole on the calibration cylinder 8 is simultaneously moved to a position that intersects with the mounting hole on the molding body 3, i.e., the calibration hole and the mounting hole are not coaxial. The external measuring equipment is prior art known to those skilled in the art and will not be described in detail here.

[0067] S4. From the inside of the calibration cylinder 8 with calibration holes in S3, screw in the calibration bolts 14 into each calibration hole until the end of the calibration bolts 14 located outside the calibration cylinder 8 contacts the inner wall of the forming body 3, then stop screwing in the calibration bolts 14.

[0068] S5. From the outside of the forming body 3 in S4, screw the mounting block 11 into each mounting hole until the ball bearing 12 on the mounting block 11 contacts the outer wall of the calibration cylinder 8, then stop screwing the mounting block 11 in. This ensures that the distance between each ball bearing 12 and the inner wall of the forming body 3 is the same (1mm in this embodiment), which in turn ensures the smooth operation of subsequent lubrication of the workpiece 13.

[0069] S6. Tighten each calibration bolt 14 in the reverse direction to disengage each calibration bolt 14 from the inner wall of the forming device body 3. Then, using external hoisting equipment, lift the calibration cylinder 8 from the cylindrical structure of the forming device body 3 through the hoisting hole 9, thereby completing the calibration of the tunnel pipe forming device.

[0070] Example 2 The difference between this embodiment and embodiment 1 is that when the calibration cylinder 8 is located inside the forming device body 3 to calibrate the tunnel tube forming device, instead of a calibration bolt 14, a mounting block 11 with ball bearings 12 is screwed into the calibration hole on the calibration cylinder 8. And when the ball bearings 12 come into contact with the inner wall of the forming device body 3, the screwing of the mounting block 11 into the calibration hole is stopped.

[0071] When it is necessary to lift the calibration cylinder 8 out from the inside of the cylindrical structure of the molding body 3, in this embodiment, it is not necessary to reverse the rotation of each mounting block 11 to disengage the ball bearing 12 from the inner wall of the molding body 3. The calibration cylinder 8 can be lifted directly from inside the cylindrical structure of the molding body 3. That is, during the lifting process of the calibration cylinder 8, the ball bearing 12 will roll against the inner wall of the molding body 3, and thus will not slide or rub against the inner wall of the molding body 3. Therefore, it is not necessary to reverse the rotation of each mounting block 11, which greatly saves labor costs.

[0072] The above embodiments of the present invention can be combined with each other and have corresponding technical effects.

[0073] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A device for forming tunnel pipes, characterized in that, It includes a support mechanism, a molding body (3), and a lubrication mechanism, wherein: The molding body (3) is detachably installed on the top of the support mechanism, and the molding body (3) is a hollow cylindrical structure. A plurality of the lubrication mechanisms are detachably installed on the molding body (3), and one end of the lubrication mechanism protrudes from the inner wall of the cylindrical structure of the molding body (3). The cylindrical structure of the forming body (3) is used to accommodate and form the workpiece (13). During the forming process of the workpiece (13), the end of the lubrication mechanism protruding from the inner wall of the cylindrical structure of the forming body (3) slides and engages with the outer wall of the workpiece (13) within the cylindrical structure of the forming body (3). The lubrication mechanism includes ball bearings (12). The forming body (3) has several mounting holes. Several ball bearings (12) are respectively limited and installed in several mounting holes, and the ball bearings (12) are slidably connected to the mounting holes. One end of the ball bearing (12) away from the mounting hole it mates with protrudes from the inner wall of the cylindrical structure of the forming body (3) and slides in mate with the outer wall of the workpiece (13). The lubrication mechanism further includes mounting blocks (11), and several mounting blocks (11) are detachably mounted in several mounting holes; the ball (12) is slidably mounted on the mounting block (11) and the ball (12) is slidably connected to the mounting block (11), and the ball (12) is connected to the mounting hole through the mounting block (11); A plurality of the mounting blocks (11) are threadedly connected to a plurality of the mounting holes, and there is friction between the threads on the outer wall of the mounting block (11) and the threads on the wall of the mounting hole; The tunnel tube forming device further includes a calibration cylinder (8), which is used to calibrate the lubrication mechanism on the forming body (3). The calibration cylinder (8) is a hollow structure and is located inside the cylindrical structure of the forming body (3). The calibration cylinder (8) is coaxially arranged with the forming body (3) and has a clearance fit with the inner wall of the forming body (3). A plurality of calibration mechanisms are arranged circumferentially on the calibration cylinder (8). One end of the calibration mechanism located outside the calibration cylinder (8) is used to abut against the inner wall of the forming body (3).

2. The apparatus for forming tunnel pipes according to claim 1, characterized in that, The molding body (3) has a spiral structure.

3. The apparatus for forming tunnel pipes according to claim 1, characterized in that, The support mechanism includes a base (1) and a leg (2), the leg (2) being detachably mounted on the top of the base (1), and the molding body (3) being detachably mounted on the top of the leg (2).

4. The tunnel tube forming apparatus according to claim 3, characterized in that, A pad (4) is installed at the top of the base (1). The pad (4) is positioned corresponding to the entrance of the molding body (3). The thickness of the pad (4) is the same as the wall thickness at the entrance of the molding body (3).

5. The apparatus for forming tunnel pipes according to claim 1, characterized in that, The calibration mechanism includes a calibration groove (10) on the outer wall of the calibration cylinder (8), a calibration hole is provided in the calibration groove (10), and a calibration bolt (14) is threaded in the calibration hole; when the calibration cylinder (8) calibrates the lubrication mechanism on the molding body (3), one end of the calibration bolt (14) located outside the calibration cylinder (8) abuts against the inner wall of the molding body (3).

6. The apparatus for forming tunnel pipes according to claim 1, characterized in that, The calibration cylinder (8) has several hoisting holes (9) at one end.

Images