Rapid pipe contracting device for metal pipeline

Abstract

The invention relates to the technical field of metal stamping, in particular to a metal pipeline rapid shrinkage device which comprises a rack, a die and a clamping piece, the die comprises an inner die and an outer die, the outer die is arranged on the rack and can move along a first axis, the inner die is arranged in the outer die, and the clamping piece is arranged on the rack. The inner mold and the outer mold can relatively move along a first axis and relatively rotate around the first axis, the clamping piece and the mold are arranged at an interval along the first axis, and the clamping piece is arranged on the rack and used for clamping a metal pipeline. The inner mold, the outer mold and the clamping piece are arranged, and in the whole pipe shrinking process of the metal pipeline, the metal pipeline, the clamping piece and the inner mold synchronously rotate around the first axis, so that the metal pipeline is more uniformly formed in the circumferential direction under the extrusion action of the inner mold and the outer mold; and local stress concentration in the metal pipeline reducing process can be reduced, so that the probability of quality defects such as bumps or wrinkles in the metal pipeline reducing process is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of metal stamping, in particular to a metal pipeline quick shrinking device. Background Art

[0002] A metal pipe reducer is a mechanical device specifically used to change the diameter of a pipe. It is mainly used to reduce one end or part of a metal pipe to a smaller diameter to meet specific connection requirements or to achieve connectivity of a fluid transmission system by assembling joints of different specifications.

[0003] The core structure of the existing pipe shrinking device is an inner mold and an outer mold. The inner mold is used to support the inside of the pipe to prevent the inner wall of the pipe from deforming during the shrinking process, and the outer mold is used to apply pressure to the outside of the pipe to gradually reduce the diameter of one end of the pipe. However, the existing metal pipe shrinking device has the following problems when forming the pipe: during the process of pipe extrusion forming, the forming position of the metal pipe is prone to bulges and wrinkles due to extrusion, which will cause the quality of the metal pipe's peripheral wall to deteriorate. Summary of the invention

[0004] Based on this, it is necessary to provide a metal pipe rapid pipe shrinking device to address the problems existing in the current metal pipe shrinking device, so as to solve the problem of the deterioration of the surrounding wall quality of the metal pipe during the shrinking process.

[0005] The above purpose is achieved through the following technical solutions: A metal pipe quick shrinking device comprises: frame; The mold includes an inner mold and an outer mold, the outer mold is arranged on the frame, the outer mold can move along the first axis, the inner mold is arranged inside the outer mold, and the inner mold and the outer mold can move relative to each other along the first axis and rotate relative to each other around the first axis; A clamping member, the clamping member and the mold are spaced apart along the first axis, the clamping member is arranged on the frame, and the clamping member is used to clamp the metal pipe. In the clamping state, the clamping member can move along the first axis and rotate around the first axis, so that the metal pipe and the clamping member rotate synchronously around the first axis and move relatively along the first axis; When shrinking the tube, the clamping member moves along the first axis and rotates around the first axis. At the same time, the outer mold moves along the first axis so that the shrinking end of the metal pipe is inserted between the outer mold and the inner mold, so that the metal pipe and the clamping member rotate synchronously around the first axis and move relatively along the first axis, and the metal pipe and the inner mold rotate synchronously around the first axis and move relatively along the first axis, and the metal pipe and the outer mold move relatively along the first axis and rotate relatively around the first axis.

[0006] Preferably, the inner mold and the clamping member rotate in opposite directions.

[0007] Preferably, the inner mold is spirally fitted inside the outer mold.

[0008] Preferably, a plurality of long bosses are provided at equal intervals in the circumferential direction on the outer circumferential surface of the inner mold.

[0009] Preferably, the clamping member comprises a first clamping cylinder and a second clamping cylinder, the axes of the first clamping cylinder and the second clamping cylinder coincide with each other, the first clamping cylinder is screw-fitted inside the frame, the second clamping cylinder is rotatably arranged inside the frame, and the first clamping cylinder and the second clamping cylinder can synchronously rotate around the first axis and relatively move along the first axis; The inner diameters of the first clamping tube and the second clamping tube are the same, and the inner diameters of the first clamping tube and the second clamping tube are matched with the outer diameter of the metal pipe.

[0010] Preferably, radial pressure components are provided inside the first clamping cylinder and the second clamping cylinder, and the radial pressure components are used to increase the positive pressure between the first clamping cylinder and the metal pipe.

[0011] Preferably, the radial pressure assembly includes a first oil plug and a second oil plug, an oil passage is provided inside the second clamping cylinder, both ends of the oil passage are connected to the inside of the second clamping cylinder, the first oil plug is elastically connected to one end of the oil passage close to the first clamping cylinder, and the second oil plug is elastically connected to one end of the oil passage away from the first clamping cylinder; Before the metal pipe is installed, the second oil plug extends out of the oil passage, and the first oil plug is located in the oil passage; After the metal pipe is installed, the first oil plug contacts the first clamping cylinder at a preset pressure, and the second oil plug contacts the metal pipe at a preset pressure.

[0012] Preferably, a second elastic member is provided between the first clamping cylinder and the second clamping cylinder.

[0013] Preferably, a plurality of spacing grooves are formed at equal intervals in the circumferential direction at one end of the first clamping cylinder close to the mold.

[0014] Preferably, a first elastic member is provided between the inner mold and the outer mold.

[0015] The beneficial effects of the present invention are: The present invention provides an inner mold, an outer mold and a clamping piece. During the entire shrinking process of the metal pipe, the metal pipe, the clamping piece and the inner mold rotate synchronously around the first axis, so that the metal pipe is more evenly formed in the circumferential direction under the extrusion action of the inner mold and the outer mold, which helps to reduce the local stress concentration of the metal pipe during the shrinking process, thereby reducing the probability of quality defects such as bulging or wrinkles in the metal pipe during the shrinking process. In addition, since the metal pipe can also move relative to the inner mold and the clamping piece along the first axis during shrinking, the inner mold and the clamping piece frictionally slide relative to the metal pipe along the first axis, so that the metal pipe is subjected to a pulling force from the direction of the first axis, which promotes the metal material of the metal pipe to flow along the pipe wall during the shrinking process, rather than just accumulating on one side to form wrinkles, which helps to make the material more evenly distributed in the new shape, ensuring a smooth and flat surface quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of the overall structure of a metal pipe quick shrinking device of the present invention; Figure 2 This is an exploded view of a metal pipe quick shrinking device of the present invention; Figure 3 It is a top view of a metal pipe quick shrinking device of the present invention; Figure 4 for Figure 3 Sectional view at AA in the middle; Figure 5 for Figure 4 The enlarged schematic diagram at a in the middle; Figure 6 for Figure 5 The enlarged schematic diagram of point b in the middle; Figure 7 for Figure 6 The enlarged schematic diagram of point c in the middle; Figure 8 for Figure 6 The enlarged schematic diagram at point d in the middle; Fig. 9 It is a schematic diagram of the working state of a clamping member in a metal pipe quick shrinking device of the present invention; Fig.10 for Fig. 9 The enlarged schematic diagram at b1 in the middle; Fig.11 for Fig.10 The enlarged schematic diagram of c1 in the middle; Fig.12 for Fig.10 The enlarged schematic diagram at d1 in the middle; Fig.13 This is a schematic diagram of the working state of a metal pipe quick shrinking device of the present invention; Fig.14 for Fig.13 The enlarged schematic diagram at e in the middle; Fig.15 It is a structural schematic diagram of an inner mold in a metal pipe rapid shrinking device of the present invention; Fig.16 The present invention is a schematic structural diagram of a first clamping tube in a metal pipe rapid shrinking device.

[0017] in: 100, rack; 210, inner mold; 211, long boss; 220, outer mold; 221, gradient hole; 230, first hydraulic cylinder; 240, first elastic member; 300, clamping member; 310, first clamping cylinder; 311, spacing groove; 320, second clamping cylinder; 321, oil passage; 330, second elastic member; 340, long slider; 350, long slide groove; 410, first oil plug; 420, second oil plug; 430, sliding roller; 440, filling hole; 1000.Metal pipes. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0019] The serial numbers assigned to the components herein, such as "first", "second", etc., are only used to distinguish the objects described and do not have any order or technical meaning. The "connection" and "coupling" mentioned in the present invention, unless otherwise specified, include direct and indirect connections (couplings). In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention.

[0020] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0021] like Figures 1 to 16 As shown, a metal pipe quick shrinking device includes a frame 100, a mold and a clamping member 300, the mold includes an inner mold 210 and an outer mold 220, the outer mold 220 is arranged on the frame 100, the outer mold 220 can move along a first axis, the inner mold 210 is arranged inside the outer mold 220, the inner mold 210 and the outer mold 220 can move relative to each other along the first axis and rotate relative to each other around the first axis, the clamping member 300 and the mold are spaced apart along the first axis, the clamping member 300 is arranged on the frame 100, the clamping member 300 is used to clamp the metal pipe 1000, in the clamping state, the clamping member 300 can move along the first axis and rotate around the first axis, so that the metal pipe 100 0 and the clamping member 300 rotate synchronously around the first axis and move relatively along the first axis. When shrinking the tube, the clamping member 300 moves along the first axis and rotates around the first axis. At the same time, the outer mold 220 moves along the first axis so that the shrinking end of the metal pipe 1000 is inserted between the outer mold 220 and the inner mold 210, so that the metal pipe 1000 and the clamping member 300 rotate synchronously around the first axis and move relatively along the first axis, and the metal pipe 1000 and the inner mold 210 rotate synchronously around the first axis and move relatively along the first axis, and the metal pipe 1000 and the outer mold 220 move relatively along the first axis and rotate relatively around the first axis.

[0022] Before shrinking the pipe, the staff first clamps the metal pipe 1000 with the clamp 300 and restricts the metal pipe 1000 from moving along the first axis, and then moves the clamp 300 along the first axis and rotates around the first axis. At the same time, the outer mold 220 moves along the first axis so that the shrinking end of the metal pipe 1000 is inserted between the outer mold 220 and the inner mold 210. In this process, the end of the metal pipe 1000 to be shrunk is squeezed by the inner mold 210 and the outer mold 220, and the diameter gradually decreases, so that the metal pipe The pressure between the metal pipe 1000 and the inner mold 210 and the outer mold 220 also increases accordingly. At this time, the clamp 300, the metal pipe 1000 and the inner mold 210 rotate synchronously, so that the metal pipe 1000 is more evenly formed in the circumferential direction under the extrusion of the inner mold 210 and the outer mold 220, which helps to reduce the local stress concentration of the metal pipe 1000 during the shrinking process, thereby reducing the probability of quality defects such as bulges or wrinkles in the metal pipe 1000 during the shrinking process. In addition, the circumferential rotation of the metal pipe 1000 also has It helps to repair the scratches or bulges that may exist on the surface of the metal pipe 1000, and improve the surface roughness of the metal pipe 1000; and in this shrinking process, the clamp 300 slides axially relative to the metal pipe 1000, and the inner mold 210 and the outer mold 220 also slide axially relative to the metal pipe 1000, so the inner mold 210 and the clamp 300 slide frictionally relative to the metal pipe 1000 along the first axis, so that the metal pipe 1000 is subjected to a pulling force from the first axis direction, which promotes the metal pipe 1000 to be stretched in the process of shrinking the pipe. The metal material of 1000 flows along the pipe wall instead of just accumulating on one side to form wrinkles, which helps to distribute the material more evenly in the new shape and ensures a smooth and flat surface quality. When the shrinkage length of the metal pipe 1000 reaches the target length, the inner mold 210 and the outer mold 220 stop moving toward the side where the metal pipe 1000 is located. At this time, the shrinkage operation of the metal pipe 1000 is completed, and then the metal pipe 1000 can be removed from the clamp 300 and the inner mold 210 and the outer mold 220.

[0023] It should also be noted that if Figure 5 As shown, a gradual hole 221 is formed at one end of the outer mold 220 close to the metal pipe 1000 so that the metal pipe 1000 can be squeezed and the pipe diameter is gradually reduced.

[0024] In this embodiment, the inner mold 210 and the clamping member 300 rotate in opposite directions, so that the inner mold 210 and the clamping member 300 provide the metal pipe 1000 with torques in opposite directions. This torque helps to more evenly distribute the material of the metal pipe 1000 over the entire circumference of the metal pipe 1000 during the shrinking process, especially in the necking area of ​​the metal pipe 1000, which helps to reduce local stress concentration and the risk of wrinkles or cracks. It also helps the material to better fill the mold, especially when shrinking the thin-walled metal pipe 1000, which helps to maintain the consistency of the wall thickness of the metal pipe 1000.

[0025] In this embodiment, if Figure 5 and Fig.15 As shown, the inner mold 210 is spirally matched inside the outer mold 220. Specifically, a spiral protrusion is provided at the end of the inner mold 210, and a spiral groove is provided at a corresponding position of the inner peripheral wall of the outer mold 220, and the spiral protrusion and the spiral groove are spirally matched.

[0026] When shrinking the tube, the staff moves the outer mold 220 along the first axis so that the end of the metal pipe 1000 to be shrunk extends between the inner mold 210 and the outer mold 220. At this time, the pressure between the inner mold 210 and the metal pipe 1000 increases. At this time, as the metal pipe 1000 rotates circumferentially, the inner mold 210 rotates synchronously with the metal pipe 1000. Therefore, the inner mold 210 rotates around the first axis while also moving relative to the outer mold 220 along the first axis.

[0027] It should also be noted that if Figure 1 As shown, a first hydraulic cylinder 230 may be disposed on the frame 100 so that the telescopic end of the first hydraulic cylinder 230 is fixedly connected to the outer mold 220 , thereby the outer mold 220 is driven to move along the first axis by the movement of the telescopic end of the first hydraulic cylinder 230 .

[0028] It should also be noted that if Figure 2 and Figure 5 As shown, a first elastic member 240 is provided between the inner mold 210 and the outer mold 220 . The first elastic member 240 is used to reset the inner mold 210 and the outer mold 220 after the metal pipe 1000 is taken out from between the inner mold 210 and the outer mold 220 .

[0029] In this embodiment, a plurality of long bosses 211 are formed on the outer circumferential surface of the inner mold 210 at equal intervals in the circumferential direction.

[0030] The long boss 211 is provided to increase the friction between the metal pipe 1000 and the inner mold 210 so that the metal pipe 1000 can stably drive the inner mold 210 to rotate synchronously.

[0031] It should also be noted that the long boss 211 is provided so that the metal pipe 1000 can be easily removed from between the inner mold 210 and the outer mold 220 after shrinking.

[0032] In this embodiment, if Figure 5 and Figure 6 As shown, the clamping member 300 is a first clamping cylinder 310, and the first clamping cylinder 310 is spirally matched inside the frame 100. Specifically, a spiral protrusion is arranged on the outer peripheral wall of the first clamping cylinder 310, and a spiral groove is opened on the corresponding peripheral wall of the frame 100, and the spiral protrusion is matched in the spiral groove. A second clamping cylinder 320 is also rotatably arranged in the frame 100, and the axis of the second clamping cylinder 320 coincides with the axis of the first clamping cylinder 310. The end of the second clamping cylinder 320 away from the first clamping cylinder 310 is penetrated, so that the end of the metal pipe 1000 away from the mold is in rotational contact with the bottom of the peripheral wall hole of the frame 100, and the first clamping cylinder 310 and the second clamping cylinder 320 are rotatably connected. 0 can rotate synchronously around the first axis and move relatively along the first axis. Specifically, long sliders 340 are circumferentially evenly spaced at one end of the first clamping cylinder 310 away from the mold, and a long slide groove 350 is opened at the corresponding end of the second clamping cylinder 320. The long slide groove 350 extends along the first axis. The long slider 340 is slidably fitted in the long slide groove 350, so that the first clamping cylinder 310 and the second clamping cylinder 320 can rotate synchronously around the first axis and move relatively along the first axis. The inner diameters of the first clamping cylinder 310 and the second clamping cylinder 320 are the same, and the inner diameters of the first clamping cylinder 310 and the second clamping cylinder 320 are adapted to the outer diameter of the metal pipe 1000.

[0033] When installing the metal pipe 1000, the staff inserts the metal pipe 1000 into the first clamping cylinder 310 and the second clamping cylinder 320 so that the outer circumferential wall of the metal pipe 1000 fits with the inner circumferential wall of the first clamping cylinder 310 and the inner circumferential wall of the second clamping cylinder 320. When shrinking the tube, after the first clamping cylinder 310 is thrusted by the outer mold 220 along the first axis, the first clamping cylinder 310 moves synchronously with the outer mold 220, and under the spiral cooperation of the first clamping cylinder 310 and the frame 100, the first clamping cylinder 310 moves along the first axis while rotating around the first axis. Under the cooperation of the long slider 340 and the long slide groove 350, the second clamping cylinder 320 rotates synchronously around the first axis, so that the first clamping cylinder 310 and the second clamping cylinder 320 drive the metal pipe 1000 to rotate synchronously in the circumferential direction through friction.

[0034] It should also be noted that in order to limit the movement of the metal pipe 1000 along the first axis, specifically, the spiral fit between the first clamping cylinder 310 and the metal pipe 1000 should provide the metal pipe 1000 with an axial force direction that is away from the mold. At this time, the axial force applied to the metal pipe 1000 causes the end of the metal pipe 1000 away from the mold to abut against and rotate against the bottom of the peripheral wall hole of the frame 100.

[0035] It should also be noted that a plurality of spacing grooves 311 are circumferentially and evenly spaced at one end of the first clamping cylinder 310 close to the mold, and the spacing grooves 311 extend along the first axis toward the side away from the mold. The purpose of providing the spacing grooves 311 is to make it easier to insert the metal pipe 1000 into the first clamping cylinder 310 and to ensure a certain pre-tightening pressure between the first clamping cylinder 310 and the metal pipe 1000.

[0036] It should be additionally explained that the long sliding block 340 and the long sliding groove 350 are provided to limit the moving distance of the first clamping cylinder 310 .

[0037] It should also be noted that if Fig.14 As shown, a second elastic member 330 is disposed between the first clamping cylinder 310 and the second clamping cylinder 320. The second elastic member 330 is used to reset the first clamping cylinder 310 after the metal pipe 1000 is taken out of the first clamping cylinder 310.

[0038] In this embodiment, a radial pressure assembly is provided inside the first clamping cylinder 310 and the second clamping cylinder 320, and the radial pressure assembly is used to increase the positive pressure between the first clamping cylinder 310 and the metal pipe 1000, thereby increasing the friction between the metal pipe 1000 and the first clamping cylinder 310, so that the first clamping cylinder 310 can stably drive the metal pipe 1000 to rotate circumferentially.

[0039] In this embodiment, if Figure 7 and Figure 8As shown, the radial pressure assembly includes a first oil plug 410 and a second oil plug 420. An oil passage 321 is provided inside the second clamping cylinder 320. Both ends of the oil passage 321 are connected to the inside of the first clamping cylinder 310. The first oil plug 410 is elastically connected to one end of the oil passage 321 close to the first clamping cylinder 310. Specifically, one end of the oil passage 321 close to the first clamping cylinder 310 is connected to the bottom of the long slide groove 350. When the first oil plug 410 extends from the oil passage 321, the oil passage 321 is connected to the bottom of the long slide groove 350. When the metal pipe 1000 is installed, the first oil plug 410 is able to contact the long slider 340, and the second oil plug 420 is elastically connected to the end of the oil passage 321 away from the first clamping cylinder 310. Before the metal pipe 1000 is installed, the second oil plug 420 extends out of the oil passage 321, and the first oil plug 410 is located in the oil passage 321. After the metal pipe 1000 is installed, the first oil plug 410 contacts the first clamping cylinder 310 at a preset pressure, and the second oil plug 420 contacts the metal pipe at a preset pressure.

[0040] Before the metal pipe 1000 is installed, the second oil plug 420 extends to the outside of the oil passage 321, and the first oil plug 410 is located inside the oil passage 321. When the metal pipe 1000 is inserted into the first clamping cylinder 310, the second oil plug 420 moves to the inside of the oil passage 321 under the squeezing action of the metal pipe 1000. At this time, the hydraulic oil in the oil passage 321 is squeezed, so that the positive pressure between the first oil plug 410 and the long slider 340 increases, which indirectly increases the positive pressure between the long slider 340 and the metal pipe 1000, thereby increasing the friction between the long slider 340 and the metal pipe 1000, thereby increasing the friction between the metal pipe 1000 and the first clamping cylinder 310. At the same time, the positive pressure between the metal pipe 1000 and the second clamping cylinder 320 increases, and the friction between the metal pipe 1000 and the second clamping cylinder 320 increases, so that the first clamping cylinder 310 can stably drive the metal pipe 1000 to rotate circumferentially.

[0041] It should also be noted that in order to prevent the first oil plug 410 and the second oil plug 420 from wearing out when the first clamping cylinder 310 and the metal pipe 1000 move relative to each other along the first axis, sliding rollers 430 are rotatably provided on the outer sides of the first oil plug 410 and the second oil plug 420 .

[0042] It should be additionally explained that a filling hole 440 is provided on the second clamping cylinder 320 , and the filling hole 440 is connected to the oil passage 321 for injecting hydraulic oil into the oil passage 321 .

[0043] The working principle of the metal pipe quick shrinking device provided in the above embodiment is: During the tube shrinking operation, the staff first inserts the non-shrinking end of the metal pipe 1000 into the first clamping cylinder 310 and the second clamping cylinder 320. When the metal pipe 1000 contacts the sliding roller 430, the sliding roller 430 is squeezed, so that the sliding roller 430 drives the second oil plug 420 to move into the oil passage 321. At this time, the pressure between the sliding rollers 430 corresponding to the metal pipe 1000 and the second oil plug 420 increases. At the same time, due to the increase in the pressure of the hydraulic oil on the first oil plug 410, the first oil plug 410 drives the corresponding sliding roller 430 to move outward, so that the sliding roller 430 corresponding to the first oil plug 410 is pressed against the long sliding roller 430. As the pressure of the block 340 increases, the pressure between the long slider 340 and the metal pipe 1000 also increases accordingly, so the first clamping cylinder 310 and the second clamping cylinder 320 can stably drive the metal pipe 1000 to rotate synchronously. Next, the staff starts the first hydraulic cylinder 230, and the first hydraulic cylinder 230 drives the outer mold 220 and the inner mold 210 to move synchronously toward the metal pipe 1000. When the outer mold 220 and the first clamping cylinder 310 abut against each other, the first clamping cylinder 310 is subjected to the thrust of the outer mold 220 and rotates circumferentially and moves along the first axis toward the direction away from the mold. The second elastic member 330 is gradually compressed. At the same time, the metal The end of the metal pipe 1000 to be shrunk gradually extends between the inner mold 210 and the outer mold 220. As the telescopic end of the first hydraulic cylinder 230 continues to extend outward, the diameter of the end of the metal pipe 1000 to be shrunk gradually shrinks to fit between the circular hole sections of the inner mold 210 and the outer mold 220 under the guidance of the gradual hole 221. At this time, the pressure between the metal pipe 1000 and the inner mold 210 and the outer mold 220 increases, so the metal pipe 1000 can drive the inner mold 210 to rotate circumferentially. At this time, the inner mold 210 rotates synchronously with the metal pipe 1000, and under the spiral transmission between the inner mold 210 and the outer mold 220, The inner mold 210 rotates circumferentially and moves along the first axis in a direction away from the metal pipe 1000, so the first elastic member 240 is gradually compressed. When the shrinkage length of the first hydraulic cylinder 230 reaches the target length, the telescopic end of the first hydraulic cylinder 230 stops extending outward. After a certain period of time, the telescopic end of the first hydraulic cylinder 230 moves in the opposite direction to the initial position. At this time, the inner mold 210 is reset to the initial position under the action of the first elastic member 240. Next, the staff removes the metal pipe 1000 from between the first clamping cylinder 310 and the second clamping cylinder 320. At this time, the first clamping cylinder 310 is reset to the initial position under the action of the second elastic member 330. Repeat the above steps to shrink the next metal pipe 1000, and the details will not be repeated.

[0044] It should be supplemented that the spiral pitch between the inner mold 210 and the outer mold 220 is greater than the spiral pitch between the first clamping cylinder 310 and the frame 100. In this way, when the metal pipe 1000 rotates one circle, the distance moved by the inner mold 210 is greater than the distance moved by the first clamping cylinder 310, and the inner mold 210 can move relative to the metal pipe 1000 along the first axis.

[0045] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0046] The above-described embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the attached claims.

Claims

1. A metal pipe rapid shrinking device, characterized in that: include: frame; The mold includes an inner mold and an outer mold, the outer mold is arranged on the frame, the outer mold can move along the first axis, the inner mold is arranged inside the outer mold, and the inner mold and the outer mold can move relative to each other along the first axis and rotate relative to each other around the first axis; A clamping member, the clamping member and the mold are spaced apart along the first axis, the clamping member is arranged on the frame, and the clamping member is used to clamp the metal pipe. In the clamping state, the clamping member can move along the first axis and rotate around the first axis, so that the metal pipe and the clamping member rotate synchronously around the first axis and move relatively along the first axis; When shrinking the tube, the clamping member moves along the first axis and rotates around the first axis. At the same time, the outer mold moves along the first axis so that the shrinking end of the metal pipe is inserted between the outer mold and the inner mold, so that the metal pipe and the clamping member rotate synchronously around the first axis and move relatively along the first axis, and the metal pipe and the inner mold rotate synchronously around the first axis and move relatively along the first axis, and the metal pipe and the outer mold move relatively along the first axis and rotate relatively around the first axis.

2. A metal pipe quick shrinking device according to claim 1, characterized in that: The inner mold and the clamping member rotate in opposite directions.

3. A metal pipe rapid shrinking device according to claim 2, characterized in that: The inner mold is spirally fitted inside the outer mold.

4. A metal pipe rapid shrinking device according to claim 3, characterized in that: The outer peripheral surface of the inner mold is provided with a plurality of long bosses at equal intervals in the circumferential direction.

5. A metal pipe quick shrinking device according to claim 2, characterized in that: The clamping member is a first clamping cylinder, which is screwed into the frame. A second clamping cylinder is also rotatably arranged in the frame. The axis of the second clamping cylinder coincides with that of the first clamping cylinder. The end of the second clamping cylinder away from the first clamping cylinder is passed through so that the end of the metal pipe away from the mold is in rotational contact with the bottom of the peripheral wall hole of the frame. The first clamping cylinder and the second clamping cylinder can rotate synchronously around the first axis and move relatively along the first axis.

6. A metal pipe rapid shrinking device according to claim 5, characterized in that: A radial pressure component is provided inside the first clamping cylinder and the second clamping cylinder, and the radial pressure component is used to increase the positive pressure between the first clamping cylinder and the metal pipe.

7. A metal pipe rapid shrinking device according to claim 6, characterized in that: The radial pressure assembly includes a first oil plug and a second oil plug. An oil passage is provided inside the second clamping cylinder. Both ends of the oil passage are connected to the inside of the second clamping cylinder. The first oil plug is elastically connected to one end of the oil passage close to the first clamping cylinder, and the second oil plug is elastically connected to one end of the oil passage away from the first clamping cylinder. Before the metal pipe is installed, the second oil plug extends out of the oil passage, and the first oil plug is located in the oil passage; After the metal pipe is installed, the first oil plug contacts the first clamping cylinder at a preset pressure, and the second oil plug contacts the metal pipe at a preset pressure.

8. A metal pipe rapid shrinking device according to claim 6, characterized in that: A second elastic member is disposed between the first clamping cylinder and the second clamping cylinder.

9. A metal pipe rapid shrinking device according to claim 5, characterized in that: A plurality of spacing grooves are formed at equal intervals in the circumferential direction on one end of the first clamping cylinder close to the mold.

10. A metal pipe rapid shrinking device according to claim 1, characterized in that: A first elastic member is arranged between the inner mold and the outer mold.

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