Hydraulic system for a tube end forming apparatus

Abstract

The utility model relates to the technical field of pipe orifice processing, concretely to a kind of hydraulic system of pipe orifice forming equipment, including the clamping oil cylinder and the pressing oil cylinder being fixed by connecting piece. The clamping piston of clamping oil cylinder is connected with the U-shaped inner cylinder body in pressing oil cylinder through transmission rod, and inner cylinder body is fixed with clamping jaw;Pressing piston is set to inner cylinder body inside and is connected pressing head, forms "cylinder in cylinder" nested structure. System is driven by independent control oil circuit, and hydraulic oil is respectively supplied to clamping electromagnetic reversing valve and pressing electromagnetic reversing valve by hydraulic distributor, to independently control clamping oil cylinder drive clamping jaw complete quick clamping and loosening, and control the relative motion of the inner cylinder body of pressing oil cylinder and pressing piston, complete high-pressure slow extrusion forming. Through structural innovation, the complete separation and integration of clamping and extrusion function are realized, the problems of existing technology, such as heavy equipment, high energy consumption and low efficiency, are solved, and the utility model has the advantages of compact structure, accurate control, rapid response and energy saving and high efficiency.

Description

Technical Field

[0001] This utility model mainly relates to the field of pipe end processing technology, specifically a hydraulic system for a pipe end forming equipment. Background Technology

[0002] In steel pipe manufacturing, the pipe ends often need to undergo plastic forming. In existing technologies, hydraulic equipment is often used to drive molds to extrude and form the pipe ends. Typical equipment usually uses only one large hydraulic cylinder to simultaneously complete two key actions: first, clamping and fixing the steel pipe, and second, extruding and forming the pipe ends.

[0003] This single-cylinder design has certain drawbacks. The clamping force (e.g., 125KN) and the extrusion force (e.g., 1000KN) need to be provided by the same cylinder. This requires that the cylinder and its associated pumps, valves and other hydraulic components must be able to output a total thrust of up to 1125KN. This results in a large system size and high manufacturing cost. Furthermore, when only a small clamping force is required, the system needs to supply oil to the huge extrusion mechanism, causing unnecessary energy loss.

[0004] Therefore, a hydraulic system is needed that can separate and independently control the clamping and extrusion actions, thereby achieving rapid clamping and high-pressure, slow-speed extrusion molding. Utility Model Content

[0005] The purpose of this invention is to provide a hydraulic system for a pipe forming device to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, this utility model adopts the following technical solution: a hydraulic system for a pipe forming device, comprising a clamping cylinder with a clamping piston inside, and a pressing cylinder with a pressing piston inside. The clamping cylinder and the pressing cylinder are connected to a control oil circuit to control the clamping piston and the pressing piston to move in the same axial direction. A connecting member is provided between the clamping cylinder and the pressing cylinder. A transmission rod is provided at one end of the clamping piston. The transmission rod passes through the connecting member and enters the pressing cylinder. An inner cylinder body is movably arranged axially inside the pressing cylinder. The transmission rod is connected to the inner cylinder body. A gripper is fixed on the inner cylinder body. The pressing piston is located inside the inner cylinder body, and a pressing head is connected to the outward end of the pressing piston. The control oil circuit includes an oil tank, a servo motor, a hydraulic distributor, a clamping solenoid directional valve, a pressing solenoid directional valve, a pressure relief directional valve, and a hydraulic oil pump. The input end of the hydraulic oil pump is connected to the oil tank. The servo motor is connected to and drives the hydraulic oil pump. The output end of the hydraulic oil pump is connected to the hydraulic distributor. The hydraulic distributor connects to the clamping solenoid directional valve and the pressing solenoid directional valve respectively. The clamping solenoid directional valve is connected to the clamping cylinder, and the pressing solenoid directional valve is connected to the inner cylinder body.

[0007] Preferably, the clamping cylinder is divided into a clamping zone and a loosening zone by a clamping piston. A first oil nozzle is provided on the side wall of the clamping cylinder at a position corresponding to the clamping zone, and a second oil nozzle is provided at a position corresponding to the loosening zone. The clamping solenoid directional valve includes two control terminals. The first oil nozzle is connected to one of the control terminals to input hydraulic oil from the oil tank into the clamping zone, and the second oil nozzle is connected to the other control terminal to input hydraulic oil from the oil tank into the loosening zone.

[0008] Preferably, the first nozzle is also connected to a pressure relief directional valve, which is connected back to the oil tank by the first bypass directional valve.

[0009] Preferably, the clamping cylinder has an internal movable cavity, in which the inner cylinder moves axially. The radial cross-section of the inner cylinder is U-shaped, and the gripper is located at the end of the U-shape of the inner cylinder. A spring is provided on the side of the gripper facing the clamping piston, and the clamping piston is connected to the spring. A pressure control zone is formed between the clamping piston and the bottom of the U-shape of the inner cylinder. The side wall of the inner cylinder has interconnected radial annular oil passage grooves and axial annular oil passage grooves. The radial annular oil passage grooves are connected to the pressure control zone. A third oil nozzle is provided on the side wall of the clamping cylinder. One end of the third oil nozzle is connected to the radial annular oil passage groove during the movement of the inner cylinder, and the other end of the third oil nozzle is connected to a clamping solenoid directional valve to input hydraulic oil from the oil tank into the pressure control zone.

[0010] Preferably, the third oil nozzle is connected back to the oil tank via the second bypass directional valve. After the pressure solenoid directional valve is de-energized, the spring elastically resets and drives the pressure piston to move inward, and the hydraulic oil in the pressure control zone returns to the oil tank via the second bypass directional valve.

[0011] Preferably, at least two first sealing rings are provided on the outer wall of the inner cylinder, and the first sealing rings are symmetrically distributed on both sides of the axial annular oil passage groove.

[0012] Preferably, two vents are provided on the side wall of the pressing cylinder at positions corresponding to the movable cavity, and there are also two third oil nozzles. The circumferential angle between the two vents is 90 degrees, and the circumferential angle between the two third oil nozzles is also 90 degrees.

[0013] Preferably, the connector is a welded part, one end of the clamping cylinder is the first welded part, one end of the pressing cylinder is the second welded part, and both ends of the connector are welded and fixed to the first welded part and the second welded part respectively. A second sealing ring is provided at the position through which the transmission rod penetrates the first welded part and the second welded part respectively.

[0014] Preferably, the bottom of the clamping cylinder is provided with a support seat.

[0015] Preferably, an oil temperature sensor is connected to the control oil circuit, and a cooling fan electrically connected to the oil temperature sensor is provided on one side of the control oil circuit.

[0016] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0017] 1. By setting up independent clamping cylinders and pressing cylinders, and rigidly connecting them into one unit using connectors, and nesting the U-shaped inner cylinder with grippers for clamping with the pressing piston for extrusion, a high degree of physical integration and complete functional separation of the clamping and extrusion mechanisms is achieved. This makes driving the grippers to perform rapid clamping actions and driving the pressing head to perform powerful extrusion molding two independent and controllable processes. This separation design makes the equipment structure compact and avoids the problems of large inertia, slow action, and energy waste caused by having to move a large extrusion mechanism to complete clamping in a single-cylinder solution, effectively improving response speed and energy utilization efficiency.

[0018] 2. By configuring independent solenoid directional valves for the clamping and pressing oil circuits, and adding bypass and pressure relief directional valves to the clamping oil circuit, a rapid pressure relief and return channel is provided for the clamping action, shortening the return time of the clamping mechanism. Simultaneously, the pressing oil circuit utilizes springs to achieve automatic reset of the pressing head and forced return of hydraulic oil, simplifying the control logic. The annular oil groove designed on the inner cylinder ensures continuous oil circuit connectivity during reciprocating motion. The symmetrically arranged multiple sealing rings, welded connectors, and cooling fan linked by an oil temperature sensor together constitute a highly stable system with reliable sealing and effective temperature control, ensuring the accuracy, speed, and long-term reliability of the equipment's operation.

[0019] The present invention will be explained in detail below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0020] The accompanying drawings are only used to illustrate the principles, implementation methods, applications, features, and effects of the present invention and other related contents, and should not be considered as limitations on the present invention.

[0021] In the accompanying drawings of the instruction manual:

[0022] Figure 1 This is a schematic diagram of the hydraulic system of this utility model;

[0023] Figure 2 This is a schematic diagram of the internal structure of all pistons in the extended state of this utility model;

[0024] Figure 3 This is a schematic diagram of the structure of the present invention after the removal of the mold and mold seat and the retraction of all pistons;

[0025] Figure 4 For the present utility model Figure 3 Schematic diagram of the end face structure where the intermediate clamping cylinder is located;

[0026] Figure 5For the present utility model Figure 3 Schematic diagram of the end face structure where the clamping cylinder is located;

[0027] Figure label:

[0028] 100. Clamping cylinder; 101. First welded part; 102. First oil nozzle; 103. Second oil nozzle; 104. Clamping piston; 105. Loosening area; 106. Clamping area; 107. Transmission rod; 200. Pressing cylinder; 201. Second welded part; 203. Vent; 204. Third oil nozzle; 205. Inner cylinder body; 206. Axial annular oil passage groove; 207. Pressing piston; 208. Gripper; 209. Pressing head; 210. Spring; 211. Pressure control area; 212. Movable cavity; 213. Radial annular oil passage groove 214. Slot; 215. Mold base; 300. Connector; 400. Support base; 500. Second sealing ring; 600. First sealing ring; 700. Control oil circuit; 701. Oil tank; 702. Oil suction filter; 703. Servo motor; 704. Hydraulic distributor; 705. Clamping solenoid directional valve; 706. Pressing solenoid directional valve; 707. Pressure relief directional valve; 708. First bypass directional valve; 709. Second bypass directional valve; 710. Hydraulic oil pump; 800. Oil temperature sensor; 900. Cooling fan. Detailed Implementation

[0029] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0030] The technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments.

[0031] like Figures 1 to 3 As shown, the hydraulic system of the pipe forming equipment provided by this utility model comprises a clamping cylinder 100, a pressing cylinder 200, and a connecting member 300 connecting the two. The connecting member 300 is preferably a cylindrical welded part, with its two ends welded and fixed to the first welded portion 101 of the clamping cylinder 100 and the second welded portion 201 of the pressing cylinder 200, respectively, forming a rigid integral structure. This ensures the coaxiality and structural strength between the clamping cylinder 100 and the pressing cylinder 200, providing a stable mechanical foundation for subsequent precise actions. A support base 400 is provided at the bottom of the pressing cylinder 200 for the installation and fixation of the entire equipment.

[0032] like Figures 2 to 3As shown, a clamping piston 104 is provided inside the clamping cylinder 100, dividing its inner cavity into a loosening area 105 on the left and a clamping area 106 on the right. A transmission rod 107 is connected to the left end of the clamping piston 104. The transmission rod 107 passes through the first welded part 101, the connecting piece 300, and the second welded part 201 in sequence, and extends into the clamping cylinder 200 to perform axial extension and retraction. A second sealing ring 500 is provided at the through holes of the first welded part 101 and the second welded part 201 to prevent oil leakage, effectively isolating the oil chambers of the clamping cylinder and the clamping cylinder, and preventing internal leakage from interfering with their respective actions.

[0033] like Figures 2 to 3 As shown, a movable cavity 212 is formed inside the clamping cylinder 200. An inner cylinder 205 with a U-shaped radial cross-section is disposed within the movable cavity 212 and can slide axially. The left end of the transmission rod 107 is fixedly connected to the bottom of the inner cylinder 205, so that the action of the clamping piston 104 can directly drive the inner cylinder 205 to move synchronously. Multiple grippers 208 for clamping the mold 215 are fixed on the outer side of the open end of the inner cylinder 205. The mold 215 is installed inside the external mold seat 214. In the prior art, the mold and mold seat are generally tubular. The mold seat 214 has a clamping part to accommodate the grippers 208 extending in, and the grippers 208 clamp the mold seat 214 in the circumferential direction, thereby restricting the movement of the mold 215 and the mold seat 214. A clamping piston 207 is disposed in the U-shaped cavity of the inner cylinder 205, and a clamping head 209 is connected to the left end of the clamping piston 207. A closed pressure control zone 211 is formed between the clamping piston 207 and the bottom of the inner cylinder 205. The clamping piston 207 is connected to the gripper 208 by a spring 210, which is mainly used to assist the clamping piston 207 in quickly resetting after the clamping head 209 finishes its extrusion molding action on the mold 215.

[0034] like Figures 2 to 5As shown, the inner cylinder 205 has interconnected radial annular oil passage grooves 213 and axial annular oil passage grooves 206 machined on its side wall. The radial annular oil passage groove 213 communicates with the pressure control zone 211. A third oil nozzle 204 is provided on the cylinder wall of the pressing cylinder 200. Regardless of how the inner cylinder 205 slides, the third oil nozzle 204 always maintains communication with the pressure control zone 211 through the radial annular oil passage groove 213 and the axial annular oil passage groove 206, thus solving the problem of continuous oil supply to the movable inner cylinder 205. The purpose of both oil passage grooves being annular is to ensure rapid and uniform oil supply to all parts of the pressure control zone 211, making the extrusion action fast and stable. Four first sealing rings 600 are provided on the outer wall of the inner cylinder 205. They are symmetrically distributed in pairs on the left and right sides of the axial annular oil passage groove 206, ensuring the dynamic sealing of the pressure control zone 211 under high pressure and preventing hydraulic oil leakage into the movable cavity 212. To further ensure smooth movement and sufficient oil supply, two vents 203 are provided on the side wall of the pressing cylinder 200 at positions corresponding to the movable cavity 212. There are also two third oil nozzles 204. The circumferential angles between the vents 203 and between the third oil nozzles 204 are both 90°. This layout helps to evenly deliver oil into the pressure control zone 211 and allows for ventilation of the movable cavity 212 to prevent excessive air pressure in the movable cavity 212 from affecting the movement of the inner cylinder 205.

[0035] like Figures 1 to 3 As shown, the control oil circuit 700 is the core of the system's control. The input end of the hydraulic oil pump 710 is connected to the oil tank 701 through an oil suction filter 702, which filters the hydraulic oil in the oil tank 701. The servo motor 703 is connected to and drives the hydraulic oil pump 710, and the hydraulic oil output by the hydraulic oil pump 710 is delivered to the hydraulic distributor 704. The hydraulic distributor 704 divides the oil circuit into two paths: one path is connected to the clamping control circuit of the clamping solenoid directional valve 705, and the other path is connected to the clamping control circuit of the clamping solenoid directional valve 706, realizing the hydraulic distribution from a single power source to two independent actuators.

[0036] The clamping control circuit consists of two working ports of the clamping solenoid directional valve 705 connected via oil pipes to the first oil nozzle 102 (corresponding to the clamping zone 106) and the second oil nozzle 103 (corresponding to the loosening zone 105) of the clamping cylinder 100. By controlling the energized state (DT01 or DT02) of the clamping solenoid directional valve 705, hydraulic oil can be controlled to enter the clamping zone 106 or the loosening zone 105, thereby driving the clamping piston 104 and its fixed transmission rod 107, inner cylinder 205, and gripper 208 to move left and right together, realizing the clamping and loosening action of the gripper 208, and completing the function of rapid clamping and releasing of the workpiece. A pressure relief directional valve 707 and a first bypass directional valve 708 are also connected in parallel on the pipeline of the first oil nozzle 102, used to quickly release the pressure in the clamping zone 106 after the clamping action. This design shortens the return time of the clamping mechanism and improves the cycle time of the equipment.

[0037] The clamping control circuit is connected to the third oil nozzle 204 of the clamping cylinder 200 via an oil pipe through a clamping solenoid valve 706. When the clamping solenoid valve 706 is energized, hydraulic oil enters the pressure control zone 211. At this time, the inner cylinder 205 and the gripper 208 are restricted by the mold 215 and the mold base 214. The hydraulic oil in the pressure control zone 211 pushes the clamping piston 207 and the clamping head 209 fixed thereon to move to the left, performing tube-shaped extrusion molding inside the mold 215. When the clamping solenoid valve 706 is de-energized, the spring force of the spring 210 pushes the clamping piston 207 to reset to the right, draining the hydraulic oil in the pressure control zone 211 back to the oil tank 701 through the second bypass valve 709, thus achieving rapid and automatic reset of the clamping head.

[0038] In addition, the system is equipped with an oil temperature sensor 800 and a cooling fan 900 linked to it. The oil temperature sensor 800 is installed on the pipeline of the control oil circuit 700. The oil temperature sensor 800 and the cooling fan 900 are electrically connected through a controller. When the oil temperature is too high, the fan is automatically started to cool the oil, which ensures the stability of the hydraulic oil viscosity and the life of the components, and ensures the reliability of the equipment under long-term continuous operation.

[0039] The working principle of this system is as follows:

[0040] S1. Clamping: When the servo motor 703 and the DT01 of the clamping solenoid directional valve 705 are energized, the hydraulic oil in the oil tank 701 is sequentially fed into the clamping area 106 through the oil suction filter 702, hydraulic oil pump 710, hydraulic distributor 704, DT01 and pressure relief directional valve 707. This pushes the clamping piston 104, transmission rod 107, inner cylinder 205 and clamping jaw 208 to move to the left together until the clamping jaw 208 clamps the mold seat 214. After the predetermined clamping force is reached, DT01 maintains pressure in the clamping area 106 to keep the clamping jaw 208 clamped.

[0041] S2, Extrusion: When the clamping solenoid directional valve 706 is energized, a portion of the hydraulic oil distributed by the hydraulic distributor 704 is input into the pressure control zone 211 through the clamping solenoid directional valve 706. The hydraulic oil pushes the clamping piston 207, causing it to carry the clamping head 209 to move to the left, extruding and forming the inside of the mold 215.

[0042] S3. Pressure relief of the clamping cylinder: After the compression is completed, the clamping solenoid directional valve 706 is de-energized, and the pressure control zone 211 is relieved. The spring 210 quickly pushes the clamping piston 207 to the right to reset, and the clamping head 209 retracts. During the reset process, the hydraulic oil in the pressure control zone 211 flows back to the oil tank 701 through the radial annular oil groove 213, the axial annular oil groove 206, the third oil nozzle 204, the pressure relief directional valve 707, and the first bypass directional valve 708.

[0043] S4. Clamping cylinder depressurization: The DT01 of the clamping solenoid directional valve 705 is de-energized, depressurizing the clamping area 106. The DT02 of the clamping solenoid directional valve 705 is simultaneously energized, and part of the hydraulic oil distributed by the hydraulic distributor 704 is input into the loosening area 105 through the DT02 and the second oil nozzle 103, driving the clamping piston 104 to quickly reset and retract, thereby demolding the mold 215. During the reset process, the hydraulic oil in the clamping area 106 flows back to the oil tank 701 along the second bypass directional valve 709 of the first oil nozzle 102.

[0044] S5. Cyclic operation: The formed tubes in the mold 215 are removed by external top mold equipment or manually. After the mold 215 is reloaded, the above steps are repeated.

[0045] It will be apparent to those skilled in the art that this application is not limited to the details of the exemplary embodiments described above, and that this application can be implemented in other specific forms without departing from its essential characteristics. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of this application is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this application. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A hydraulic system for a pipe forming apparatus, comprising a clamping cylinder (100) internally equipped with a clamping piston (104) and a clamping cylinder (200) internally equipped with a pressing piston (207), wherein the clamping cylinder (100) and the pressing cylinder (200) are connected to a control oil circuit (700) to control the clamping piston (104) and the pressing piston (207) to move in the same axial direction, characterized in that: A connecting member (300) is provided between the clamping cylinder (100) and the pressing cylinder (200). A transmission rod (107) is provided at one end of the clamping piston (104). The transmission rod (107) penetrates the connecting member (300) and enters the pressing cylinder (200). An inner cylinder body (205) is axially movable inside the pressing cylinder (200). The transmission rod (107) is connected to the inner cylinder body (205). A clamping claw (208) is fixed on the inner cylinder body (205). The pressing piston (207) is located inside the inner cylinder body (205), and a pressing head (209) is connected to the outward end of the pressing piston (207). The control oil circuit (700) includes an oil tank (701), a servo motor (703), a hydraulic distributor (704), a clamping solenoid directional valve (705), a pressing solenoid directional valve (706), a pressure relief directional valve (707), and a hydraulic oil pump (710). The input end of the hydraulic oil pump (710) is connected to the oil tank (701). The servo motor (703) is connected to and drives the hydraulic oil pump (710). The output end of the hydraulic oil pump (710) is connected to the hydraulic distributor (704). The clamping solenoid directional valve (705) and the pressing solenoid directional valve (706) are connected by the hydraulic distributor (704). The clamping solenoid directional valve (705) is connected to the clamping cylinder (100), and the pressing solenoid directional valve (706) is connected to the inner cylinder body (205).

2. The hydraulic system of the pipe forming equipment according to claim 1, characterized in that: The clamping cylinder (100) is divided into a clamping area (106) and a loosening area (105) by a clamping piston (104). A first oil nozzle (102) is provided on the side wall of the clamping cylinder (100) at a position corresponding to the clamping area (106). A second oil nozzle (103) is provided on the side wall of the clamping cylinder (100) at a position corresponding to the loosening area (105). The clamping solenoid reversing valve (705) includes two control terminals, DT01 and DT02. The first oil nozzle (102) is connected to DT01 to input hydraulic oil from the oil tank (701) into the clamping area (106). The second oil nozzle (103) is connected to DT02 to input hydraulic oil from the oil tank (701) into the loosening area (105).

3. The hydraulic system of the pipe forming equipment according to claim 2, characterized in that: The first nozzle (102) is also connected to a pressure relief directional valve (707), which is connected back to the oil tank (701) by a first bypass directional valve (708).

4. The hydraulic system of the pipe forming equipment according to claim 1, characterized in that: The clamping cylinder (200) forms a movable cavity (212) inside, and the inner cylinder (205) moves axially within the movable cavity (212). The radial cross-section of the inner cylinder (205) is U-shaped. The gripper (208) is located at the U-shaped end of the inner cylinder (205). A spring (210) is provided on the side of the gripper (208) facing the clamping piston (207). The clamping piston (207) is connected to the spring (210). A pressure control zone (211) is formed between the clamping piston (207) and the U-shaped bottom of the inner cylinder (205). The side wall of the 05) has a radial annular oil passage groove (213) and an axial annular oil passage groove (206) that are interconnected. The radial annular oil passage groove (213) is connected to the pressure control area (211). The side wall of the clamping cylinder (200) is provided with a third oil nozzle (204). One end of the third oil nozzle (204) is connected to the radial annular oil passage groove (213) during the movement of the inner cylinder (205). The other end of the third oil nozzle (204) is connected to the clamping solenoid reversing valve (706) to input the hydraulic oil in the oil tank (701) into the pressure control area (211).

5. The hydraulic system of the pipe forming equipment according to claim 4, characterized in that: The third oil nozzle (204) is connected back to the oil tank (701) by the second bypass directional valve (709). After the pressure solenoid directional valve (706) is de-energized, the spring (210) elastically resets and drives the pressure piston (207) to move inward. The hydraulic oil in the pressure control zone (211) returns to the oil tank (701) through the second bypass directional valve (709).

6. The hydraulic system of the pipe forming equipment according to claim 4, characterized in that: At least two first sealing rings (600) are provided on the outer wall of the inner cylinder (205), and the first sealing rings (600) are symmetrically distributed on both sides of the axial annular oil passage groove (206).

7. The hydraulic system of the pipe forming equipment according to claim 4, characterized in that: Two vents (203) are provided on the side wall of the clamping cylinder (200) at positions corresponding to the movable cavity (212). There are also two third oil nozzles (204). The circumferential angle between the two vents (203) is 90°, and the circumferential angle between the two third oil nozzles (204) is also 90°.

8. The hydraulic system of the pipe forming equipment according to claim 1, characterized in that: The connector (300) is a welded part. One end of the clamping cylinder (100) is a first welded part (101), and one end of the pressing cylinder (200) is a second welded part (201). The two ends of the connector (300) are welded and fixed to the first welded part (101) and the second welded part (201) respectively. A second sealing ring (500) is provided at the penetration position of the first welded part (101) and the second welded part (201) by the transmission rod (107).

9. The hydraulic system of the pipe forming equipment according to claim 1, characterized in that: The bottom of the clamping cylinder (200) is provided with a support base (400).

10. The hydraulic system of the pipe forming equipment according to claim 1, characterized in that: An oil temperature sensor (800) is connected to the control oil circuit (700), and a cooling fan (900) electrically connected to the oil temperature sensor (800) is provided on one side of the control oil circuit (700).

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