A water expansion machine for metal pipes

Abstract

The present invention relates to the technical field of water expansion machines, and specifically discloses a water expansion machine for metal pipe bodies, comprising: a base and a workbench, the workbench is arranged on the base, a module is arranged on the workbench, and is used for placing and shaping the metal pipe, and a water expansion machine unit is also arranged on the base, and is used for water expansion treatment of the metal pipe in the module; the module comprises a pedestal, a lower mold barrel and an upper mold barrel, the pedestal is arranged on the top of the workbench, the lower mold barrel is composed of two half-cylinders spliced ​​together, and the two half-cylinders can both rotate relative to the pedestal; the water expansion machine for metal pipe bodies of the present invention can automatically open the lower mold barrel when the upper mold barrel is lifted, and automatically close the lower mold barrel when the upper mold barrel is lowered, through the mutual cooperation of a first traction rope and a torsion component, so that the opening and closing of the lower mold barrel are both controlled by the upper mold barrel, and the lower mold barrel can be automatically opened and closed without the need to separately add a mold opening and closing machine unit, thereby reducing equipment costs and saving the trouble of manual mold opening and closing for staff.

Description

Technical Field

[0001] The present invention relates to the technical field of water expansion machines, in particular to a water expansion machine for a metal pipe. Background Art

[0002] The water expansion machine uses liquid (usually water) as a medium to apply uniform pressure in a specific mold, causing the metal or other materials to undergo plastic deformation under pressure, thereby achieving the purpose of forming. In the processing of metal pipes, the water expansion forming process can be used to produce the pipe, using the water expansion machine to expand and press the pipe into the desired shape in the mold.

[0003] When processing metal pipes on existing water expansion machines, after the metal pipes are water-expanded, the staff waits for the upper mold barrel to be lifted and separated from the lower mold barrel, and then opens the lower mold barrel to replace the metal pipe fittings. This is troublesome, inconvenient, inefficient, and has high work intensity. Although some water expansion machines have added cylinders and other mechanisms to enable the lower mold barrel to open and close automatically, in order to ensure that the lower mold barrel can be opened in the shortest time after the upper mold barrel is lifted, saving time for replacing metal pipe fittings, it is necessary to add a CNC system to coordinate the cylinder and the mold barrel. The coordination and debugging process is relatively complicated and the cost of use is high. Summary of the Invention

[0004] The present invention provides a water expansion machine for metal pipes, aiming to solve the problems in related technologies such as manual opening of a lower mold barrel is troublesome, inconvenient, inefficient, and labor-intensive, and the cost of using a numerical control system to control the opening of the lower mold barrel is high.

[0005] The water expansion machine for metal pipes of the present invention comprises a base and a workbench. The workbench is arranged on the base and provided with a module for placing and shaping the metal pipes. The base is also provided with a water expansion unit for performing water expansion treatment on the metal pipes in the module.

[0006] The die set includes a base, a lower die barrel and an upper die barrel. The base is set on the top of the workbench. The lower die barrel is composed of two half-barrels, and both half-barrels can rotate relative to the base. The upper die barrel is located directly above the lower die barrel and can be raised and lowered relative to the lower die barrel.

[0007] The two half cylinders are fixedly connected to a first traction rope, the top end of which is fixedly connected to the upper mold cylinder, so that the upper mold cylinder can pull the half cylinders to rotate and open the mold after it is lifted and separated from the lower mold cylinder;

[0008] A connecting shaft rotating in the pedestal is fixedly mounted on the half cylinder, and a torsion component is provided between the connecting shaft and the pedestal, which can drive the connecting shaft to rotate and reset after the half cylinder loses the pulling force of the first traction rope.

[0009] Preferably, an arc-shaped guide groove is provided on the outer side of the half cylinder, a guide ring is provided on the top of the workbench, and the first traction rope passes through the guide ring and is mounted inside the guide groove.

[0010] Preferably, a protection box is fixedly installed on the top of the base, a support platform is provided in the middle of the protection box, a plurality of columns are fixed on the top of the support platform in the form of a rectangular array, and a water tank is provided on the base below the protection box.

[0011] Preferably, a water expansion pipe is vertically fixed in the middle of the base, and the bottom end of the water expansion pipe is connected to the water outlet, and a plug that is adapted to the top pipe opening of the lower mold barrel is fixedly installed inside the upper mold barrel.

[0012] Preferably, a hydraulic cylinder is fixedly installed on the top of the column, a lifting platform is provided at the telescopic end of the hydraulic cylinder, and the upper mold cylinder is provided at the bottom of the lifting platform.

[0013] Preferably, the workbench is arranged on the top of the support platform and is located between multiple columns. A water injection hole is opened on the side wall of the workbench, and a water outlet hole is opened on the top of the workbench, and the water outlet hole is connected to the water injection hole.

[0014] Preferably, the water expansion unit includes a water cylinder, a piston, an oil cylinder and a water pump. The water cylinder is fixedly mounted on a base and connected to a workbench. The oil cylinder is fixedly mounted directly above the water cylinder. The piston is fixedly mounted at the output end of the oil cylinder, and the bottom end of the piston extends into the water cylinder.

[0015] Preferably, an inner cavity is provided inside the water cylinder, a connecting hole connected to the inner cavity is provided on the side wall of the water cylinder, and the connecting hole and the water injection hole are connected by a first water pipe, the piston is slidably assembled inside the inner cavity, an L-shaped water replenishment groove is provided inside the piston, the bottom end of the water replenishment groove is connected to the inner cavity, the top end of the water replenishment groove is connected to the output end of the water pump through the second water pipe, and the input end of the water pump is connected to the water tank through the third water pipe.

[0016] Preferably, a storage cylinder is fixedly installed on one side of the workbench close to the feed port, a mounting shaft is coaxially fixed inside the storage cylinder, a water-blocking cloth is wrapped around the outside of the mounting shaft, and the end of the water-blocking cloth extends to the outside of the storage cylinder and is fixed to the upper mold cylinder.

[0017] Preferably, the end of the water retaining cloth is fixedly installed with a connecting rod slidably assembled on the column, the bottom of the upper mold cylinder is fixedly installed with a second traction rope, and a ring sleeve is fixedly installed on the column, and the height of the ring sleeve is higher than the top of the lower mold cylinder, and the bottom end of the second traction rope passes through the ring sleeve and is fixed to the connecting rod.

[0018] Beneficial effects:

[0019] 1. When the present invention is in use, through the mutual cooperation of the first traction rope and the torsion component, the lower mold cylinder can be automatically opened when the upper mold cylinder is lifted, and the lower mold cylinder can be automatically closed when the upper mold cylinder is lowered, so that the opening and closing of the lower mold cylinder are both controlled by the upper mold cylinder. There is no need to separately add a mold opening and closing unit to automatically open and close the lower mold cylinder, which reduces equipment costs and saves the trouble of manual mold opening and closing for staff, making the replacement and placement of metal tubes more convenient and quick, and improving the efficiency of metal tube processing.

[0020] 2. When the present invention is in use, the water-blocking cloth is rolled up and stretched when the upper mold cylinder is raised and lowered, so that the upper mold cylinder and the lower mold cylinder can be shielded when the water is pressurized, and then the water column sprayed when the water is pressurized is blocked to prevent the water solution from spraying to the outside of the equipment. The shielding of the upper mold cylinder and the lower mold cylinder can be released when the mold is opened to facilitate the replacement of the metal tube. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a perspective view of the present invention.

[0022] Figure 2 It is a three-dimensional diagram from another angle of the present invention.

[0023] Figure 3 This invention Figure 2 Schematic diagram of the enlarged structure at point A in the middle.

[0024] Figure 4 This invention Figure 2 Schematic diagram of the enlarged structure at point B in the middle.

[0025] Figure 5 This invention Figure 2 Front view of .

[0026] Figure 6 It is a schematic diagram of the structure inside the protective box of the present invention.

[0027] Figure 7 This invention Figure 6 Schematic diagram of the enlarged structure at point C in the middle.

[0028] Figure 8 It is a sectional view of a water tank of the present invention.

[0029] Figure 9 It is a cross-sectional view of the upper mold cylinder and the lower mold cylinder of the present invention.

[0030] Figure 10 This invention Figure 9 Schematic diagram of the enlarged structure at point D in the middle.

[0031] Figure 11 It is a schematic structural diagram of the lower mold cylinder and the interior of the installation cylinder of the present invention.

[0032] Reference numerals:

[0033] 10. Base; 11. Protective box; 12. Support platform; 13. Column; 131. Ring; 14. Water tank; 20. Workbench; 21. Water injection hole; 22. Water outlet hole; 30. Module; 31. Base; 311. Water expansion pipe; 32. Lower mold cylinder; 321. Guide groove; 33. Upper mold cylinder; 331. Plug; 332. Second traction rope; 40. Lifting mechanism; 41. Hydraulic cylinder; 42. Lifting platform; 5 0. Mold opening mechanism; 51. First traction rope; 52. Guide ring; 60. Mold closing mechanism; 61. Mounting cylinder; 62. Connecting shaft; 63. Torsion component; 70. Water expansion unit; 71. Water cylinder; 711. Inner cavity; 712. Connecting hole; 72. Piston; 721. Water supply tank; 73. Oil cylinder; 74. Water pump; 80. Splash-proof mechanism; 81. Storage cylinder; 82. Mounting shaft; 83. Water retaining cloth; 831. Connecting rod. DETAILED DESCRIPTION

[0034] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0035] like Figures 1 to 11 As shown, the water swelling machine for metal pipes of the present invention includes a base 10, a workbench 20, a module 30, a lifting mechanism 40, a mold opening mechanism 50, a mold closing mechanism 60, a water swelling unit 70 and a splash-proof mechanism 80. The workbench 20 is arranged in the base 10 for supporting and injecting water into the module 30 to facilitate the placement and water swelling processing of the metal pipe. The lifting mechanism 40 is arranged above the module 30. The mold opening mechanism 50 and the mold closing mechanism 60 are arranged on one side of the module 30 and can cooperate with the lifting mechanism 40 to open and close the module 30. The water swelling unit 70 is located on one side of the workbench 20 for conveying water swelling solution into the workbench 20. The splash-proof mechanism 80 is located on one side of the module 30 to prevent the water swelling solution from being sprayed to the outside of the equipment under high pressure during water swelling.

[0036] refer to Figure 1 、 Figure 2 as well as Figure 6 A protective box 11 is fixedly installed on the top of the base 10, and a feed port is provided on one side of the protective box 11 to facilitate the taking and placing of metal pipes. A support platform 12 is provided in the middle of the protective box 11, and a plurality of columns 13 are fixed on the top of the support platform 12 in the form of a rectangular array for supporting the lifting mechanism 40. A water tank 14 is provided on the base 10 below the protective box 11 for storing the water solution. The water tank 14 is connected to the protective box 11 and can recover the water solution in the protective box 11.

[0037] refer to Figure 1 and Figure 2 The workbench 20 is arranged on the top of the support platform 12 and is located between multiple columns 13. A water injection hole 21 is opened on the side wall of the workbench 20, and a water outlet hole 22 is opened on the top of the workbench 20. The water outlet hole 22 is connected to the water injection hole 21. Water can be injected into the workbench 20 through the water injection hole 21, and then the water is discharged from the water outlet hole 22 to perform water swelling treatment on the metal pipe.

[0038] refer to Figure 2 and Figure 5 The mold assembly 30 includes a base 31, a lower mold cylinder 32 and an upper mold cylinder 33. The base 31 is arranged on the top of the workbench 20. The lower mold cylinder 32 is composed of two half cylinders, and the two half cylinders can rotate relative to the base 31. The upper mold cylinder 33 is located directly above the lower mold cylinder 32 and can be raised and lowered relative to the lower mold cylinder 32. The upper mold cylinder 33 can be inserted into the outside of the lower mold cylinder 32 during the descent, pressing the two half cylinders to prevent them from separating during the swelling process of the metal tube. The upper mold cylinder 33 can be detached from the outside of the lower mold cylinder 32 during the lifting, so that the two half cylinders can be separated, and the lower mold cylinder 32 can be opened to take, place and replace the metal tube.

[0039] refer to Figure 9 A water rising tube 311 is vertically fixed in the middle of the base 31, and the bottom end of the water rising tube 311 is connected to the water outlet 22, which is used to support the bottom end of the metal tube so that the water rising solution can be injected into the lower mold cylinder 32 from the water rising tube 311. A plug 331 that is compatible with the top pipe opening of the lower mold cylinder 32 is fixedly installed inside the upper mold cylinder 33. After the upper mold cylinder 33 is inserted into the outside of the lower mold cylinder 32, the plug 331 can be inserted into the lower mold cylinder 32 to seal the upper end pipe opening of the metal tube, thereby ensuring the sealing of the inside of the metal tube during the water rising operation.

[0040] refer to Figure 2 The lifting mechanism 40 includes a hydraulic cylinder 41 and a lifting platform 42. The hydraulic cylinder 41 is fixedly installed at the top of the column 13. The lifting platform 42 is set at the telescopic end of the hydraulic cylinder 41, and the lifting platform 42 is slidably assembled on the column 13. The upper mold cylinder 33 is fixedly installed at the bottom of the lifting platform 42. When the hydraulic cylinder 41 drives the lifting platform 42 to rise and fall, the upper mold cylinder 33 can rise and fall with the lifting platform 42.

[0041] refer to Figure 6 and Figure 7The mold opening mechanism 50 has two groups respectively arranged on the two half cylinders, which can drive the half cylinders to rotate on the base 31 after the upper mold cylinder 33 is lifted to a certain height, so that the two half cylinders are separated from each other and the lower mold cylinder 32 is opened. The two groups of mold opening mechanisms 50 include a first traction rope 51 and a guide ring 52. The top end of the first traction rope 51 is fixedly connected to the upper mold cylinder 33, and the bottom end of the first traction rope 51 is fixed to the half cylinder. The guide ring 52 is fixedly installed on the base 31. The outer wall of the half cylinder is provided with an arc. shaped guide groove 321, and the first traction rope 51 passes through the guide ring 52 and is carried inside the guide groove 321. The guide rings 52 in the two sets of mold opening mechanisms 50 are arranged relatively to each other, and the first traction ropes 51 in the two sets of mold opening mechanisms 50 are respectively fixed to the two half-cylinders, so that after the upper mold cylinder 33 is lifted and separated from the lower mold cylinder 32, the first traction rope 51 pulls the half-cylinder to rotate, so that the two half-cylinders are rotated and separated, realizing automatic mold opening of the lower mold cylinder 32 so that the metal tube can be taken in and replaced.

[0042] refer to Figure 7 and Figure 11 , the two combined mold mechanisms 60 include a mounting cylinder 61, a connecting shaft 62 and a torsion component 63. The mounting cylinder 61 is fixedly mounted inside the base 31, and the connecting shaft 62 is vertically rotatably assembled in the mounting cylinder 61. The two half cylinders are respectively fixedly mounted on the top ends of the connecting shafts 62 in the two combined mold mechanisms 60, and the torsion component 63 is arranged on the outside of the connecting shaft 62, which can drive the connecting shaft 62 to rotate and reset after the half cylinder loses the tension of the first traction rope 51. In this solution, the torsion component 63 is specifically a torsion spring, which is sleeved on the outside of the connecting shaft 62, and its two ends are respectively fixed to the mounting cylinder 61 and the connecting shaft 62. When the two half cylinders rotate to open the mold, the torsion spring can apply a torsional force to the connecting shaft 62, and then drive the two half cylinders to rotate and reset on the top of the base 31 after losing the tension of the first traction rope 51, thereby realizing the mold closing of the lower mold cylinder 32, so as to facilitate the water swelling operation of the metal tube.

[0043] refer to Figure 1 and Figure 6 The water swelling unit 70 includes a water cylinder 71, a piston 72, an oil cylinder 73 and a water pump 74. The water cylinder 71 is fixedly mounted on the base 10 and is connected to the workbench 20. The oil cylinder 73 is fixedly mounted directly above the water cylinder 71. The piston 72 is fixedly mounted at the output end of the oil cylinder 73, and the bottom end of the piston 72 extends into the water cylinder 71. It can be raised and lowered in the water cylinder 71 under the drive of the oil cylinder 73. The water pump 74 is arranged between the water tank 14 and the water cylinder 71, and can transport the water swelling solution in the water tank 14 to the water cylinder 71, so that the water swelling solution is transported to the workbench 20 through the water cylinder 71 and enters the metal pipe through the water outlet 22. The piston 72 descends to pressurize the water swelling solution being transported, and then water swelling processing is performed on the metal pipe.

[0044] refer to Figure 6 and Figure 8 The water cylinder 71 has an inner cavity 711, and a connecting hole 712 communicating with the inner cavity 711 is provided on the side wall of the water cylinder 71. The connecting hole 712 is connected to the water injection hole 21 through a first water pipe (not shown in the figure), so that the water solution in the inner cavity 711 can be transported into the workbench 20. The piston 72 is slidably assembled in the inner cavity 711. An L-shaped water replenishment groove 721 is provided in the piston 72. The bottom end of the water replenishment groove 721 is connected to the inner cavity 711, and the top end of the water replenishment groove 721 is connected to the water tank 20 through a second water pipe. The output end of the pump 74 is connected (not shown in the figure), and the input end of the water pump 74 is connected to the water tank 14 through a third water pipe (not shown in the figure), so that the water pump 74 can extract the water-swelling solution in the water tank 14 and inject it into the inner cavity 711 of the water cylinder 71 through the water replenishment groove 721 in the piston 72. Then, the water-swelling solution in the inner cavity 711 is injected into the interior of the workbench 20 through the water injection hole 21. As the piston 72 descends and compresses the space in the inner cavity 711, the water-swelling solution being transported can be pressurized, thereby realizing the water-swelling operation of the metal pipe.

[0045] refer to Figure 10 When the upper mold cylinder 33 rises, the water-blocking cloth 83 can be rolled up into the storage cylinder 81 by the coil spring to avoid blocking and affecting the replacement of the metal tube.

[0046] refer to Figure 2-Figure 4 The end of the water-retaining cloth 83 is installed with a connecting rod 831 that is slidably assembled on the column 13. A second traction rope 332 is fixedly installed on the bottom of the upper mold cylinder 33. A ring sleeve 131 is fixedly installed on the column 13, and the height of the ring sleeve 131 is higher than the top height of the lower mold cylinder 32. The bottom end of the second traction rope 332 passes through the ring sleeve 131 and is fixed to the connecting rod 831, so that the water-retaining cloth 83 can be pulled out when the upper mold cylinder 33 descends and be rolled up when the upper mold cylinder 33 rises.

[0047] Working principle: The hydraulic cylinder 41 drives the lifting platform 42 to rise, so that the upper mold cylinder 33 is raised and separated from the lower mold cylinder 32. The first traction rope 51 pulls the half cylinder to rotate, so that the two half cylinders move away from each other to open the mold of the lower mold cylinder 32. Then, the metal tube is inserted into the water-rising tube 311 in the base 31, so that the lifting platform 42 drives the upper mold cylinder 33 to descend. The half cylinder gradually loses the pulling force of the first traction rope 51 and rotates and resets under the action of the torsion component 63, so that the two half cylinders move closer to each other to complete the mold closing of the lower mold cylinder 32. Then, the upper mold cylinder 33 is inserted into the outside of the lower mold cylinder 32 to fix it during the descent, so that the plug 331 enters the lower mold cylinder 32 to seal the top of the metal tube.

[0048] The water pump 74 pumps the water solution from the water storage tank 14 into the inner cavity 711 of the water cylinder 71 through the water supply groove 721 in the piston 72. The water solution is then injected into the workbench 20 through the water injection hole 21 and fed into the metal pipe through the water expansion pipe 311. As the piston 72 descends, the space in the inner cavity 711 is compressed, thereby increasing the pressure of the water solution being transported, thereby achieving the water expansion operation of the metal pipe. The upper mold cylinder 33 is then lifted, and the lower mold cylinder 32 is opened to remove the formed metal pipe.

[0049] As the upper mold cylinder 33 descends and enters the outside of the lower mold cylinder 32, the water-blocking cloth 83 can be pulled out of the storage cylinder 81 through the second traction rope 332 to cover the upper mold cylinder 33 and the lower mold cylinder 32, thereby blocking the water-blocking solution splashed out during the water-blocking process for easy recovery.

[0050] The present invention cooperates with the first traction rope 51 and the torsional component 63 to automatically open the lower mold cylinder 32 when the upper mold cylinder 33 is lifted, and automatically close the lower mold cylinder 32 when the upper mold cylinder 33 is lowered, so that the opening and closing of the lower mold cylinder 32 are both controlled by the upper mold cylinder 33, and the lower mold cylinder 32 can be opened and closed automatically without the need to separately add a mold opening and closing unit, thereby reducing equipment costs and eliminating the trouble of manual mold opening and closing for staff, making the replacement and placement of metal tubes more convenient and quick, and improving the processing efficiency of metal tubes; the water-blocking cloth 83 is wound and stretched when the upper mold cylinder 33 is raised and lowered, so that the upper mold cylinder 33 and the lower mold cylinder 32 can be shielded when the pressurized water rises, and then the water column sprayed when the water rises and pressurizes can be blocked to prevent the water-rising solution from spraying to the outside of the equipment, and the shielding of the upper mold cylinder 33 and the lower mold cylinder 32 can be removed when the mold is opened to facilitate the replacement of the metal tube.

[0051] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A water expansion machine for a metal pipe, comprising a base (10) and a workbench (20), wherein the workbench (20) is arranged on the base (10), and is characterized in that: A module (30) is provided on the workbench (20) for placing and shaping the metal pipes, and a water swelling unit (70) is provided on the base (10) for performing water swelling treatment on the metal pipes in the module (30); The die set (30) includes a pedestal (31), a lower die barrel (32) and an upper die barrel (33). The pedestal (31) is arranged on the top of the workbench (20). The lower die barrel (32) is composed of two half barrels spliced ​​together, and both half barrels can rotate relative to the pedestal (31). The upper die barrel (33) is located directly above the lower die barrel (32) and can be raised and lowered relative to the lower die barrel (32). The two half cylinders are fixedly connected to a first traction rope (51), the top end of which is fixedly connected to the upper mold cylinder (33), so that the upper mold cylinder (33) can pull the half cylinders to rotate and open the mold after being lifted and separated from the lower mold cylinder (32); A connecting shaft (62) is fixedly mounted on the half cylinder and rotates in the pedestal (31), and a torsion component (63) is provided between the connecting shaft (62) and the pedestal (31), which can drive the connecting shaft (62) to rotate and reset after the half cylinder loses the pulling force of the first traction rope (51).

2. The water expansion machine for metal pipes according to claim 1, characterized in that: An arc-shaped guide groove (321) is provided on the outer side of the half cylinder, a guide ring (52) is provided on the top of the workbench (20), and the first traction rope (51) passes through the guide ring (52) and is mounted inside the guide groove (321).

3. The water expansion machine for metal pipes according to claim 2, characterized in that: A protection box (11) is fixedly mounted on the top of the base (10), a support platform (12) is provided in the middle of the protection box (11), a plurality of columns (13) are fixed on the top of the support platform (12) in the form of a rectangular array, and a water storage tank (14) is provided on the base (10) and is located below the protection box (11).

4. The water expansion machine for metal pipes according to claim 3, characterized in that: A water rising pipe (311) is vertically fixed in the middle of the pedestal (31), and the bottom end of the water rising pipe (311) is connected to the water outlet (22). A plug (331) adapted to the top pipe opening of the lower mold cylinder (32) is fixedly installed inside the upper mold cylinder (33).

5. The water expansion machine for metal pipes according to claim 3, characterized in that: A hydraulic cylinder (41) is fixedly mounted on the top of the column (13), a lifting platform (42) is provided at the telescopic end of the hydraulic cylinder (41), and an upper mold cylinder (33) is provided at the bottom of the lifting platform (42).

6. The water expansion machine for metal pipes according to claim 5, characterized in that: The workbench (20) is arranged on the top of the support platform (12) and is located between the plurality of columns (13). A water injection hole (21) is provided on the side wall of the workbench (20). A water outlet hole (22) is provided on the top of the workbench (20), and the water outlet hole (22) is connected to the water injection hole (21).

7. The water expansion machine for metal pipes according to claim 6, characterized in that: The water expansion unit (70) comprises a water cylinder (71), a piston (72), an oil cylinder (73) and a water pump (74). The water cylinder (71) is fixedly mounted on the base (10) and is connected to the workbench (20). The oil cylinder (73) is fixedly mounted directly above the water cylinder (71). The piston (72) is fixedly mounted at the output end of the oil cylinder (73), and the bottom end of the piston (72) extends into the water cylinder (71).

8. The water expansion machine for metal pipes according to claim 7, characterized in that: The water cylinder (71) has an inner cavity (711) formed therein, a connecting hole (712) communicating with the inner cavity (711) formed on a side wall of the water cylinder (71), and the connecting hole (712) is connected to the water injection hole (21) via a first water pipe. The piston (72) is slidably assembled inside the inner cavity (711), and an L-shaped water replenishment groove (721) is formed inside the piston (72). The bottom end of the water replenishment groove (721) is connected to the inner cavity (711), and the top end of the water replenishment groove (721) is connected to the output end of the water pump (74) via a second water pipe. The input end of the water pump (74) is connected to the water storage tank (14) via a third water pipe.

9. The water expansion machine for metal pipes according to claim 3, characterized in that: A storage cylinder (81) is fixedly installed on one side of the workbench (20) close to the feed port, a mounting shaft (82) is coaxially fixed inside the storage cylinder (81), a water-blocking cloth (83) is wound around the outside of the mounting shaft (82), and an end of the water-blocking cloth (83) extends to the outside of the storage cylinder (81) and is fixed to the upper mold cylinder (33).

10. The water expansion machine for metal pipes according to claim 9, characterized in that: A connecting rod (831) slidably mounted on the column (13) is fixedly mounted on the end of the water retaining cloth (83); a second traction rope (332) is fixedly mounted on the bottom of the upper mold cylinder (33); a ring sleeve (131) is fixedly mounted on the column (13), and the height of the ring sleeve (131) is higher than the top of the lower mold cylinder (32); the bottom end of the second traction rope (332) passes through the ring sleeve (131) and is fixed to the connecting rod (831).

Images