An active telescopic exhaust pipe for a steel pipe hydrostatic testing machine

Abstract

This invention relates to an active telescopic exhaust pipe for a steel pipe hydrostatic testing machine. The exhaust pipe is installed at the exhaust end of the hydrostatic testing machine and is hydraulically driven for lifting. Its structure consists of multiple sleeves with inner annular cavities connected in sequence. A central shaft runs through the telescopic sleeves to guide air. By supplying pressure within the sleeves with inner annular cavities, the multiple sections of the telescopic sleeve extend, achieving lifting and exhaust. This hydraulic active telescopic air guiding overcomes the drawbacks of uncontrollable floating lifting. The air guide tube is unaffected by water level, the hydraulic lifting has good balance, and the air guide pipe is unaffected by floating. A displacement sensor can be easily installed to monitor the lifting process. It offers advantages such as strong controllability, good safety, high efficiency, and small size.

Description

Technical Field

[0001] This invention relates to a steel pipe hydrostatic testing machine, specifically an active telescopic exhaust pipe for a steel pipe hydrostatic testing machine. Background Technology

[0002] A hydrostatic testing machine is a device used to conduct pressure tests on steel pipes, spiral welded pipes, cast iron pipes, etc. The purpose is to inspect the quality of the steel pipes and determine whether they meet relevant standards and user needs. It is a quality inspection device suitable for various steel pipe manufacturing enterprises.

[0003] When testing steel pipes with a hydrostatic testing machine, both ends must be sealed. Low-pressure water is filled into the steel pipe through a filling valve, followed by a high-pressure test. During this process, air is present inside the pipe, requiring an exhaust channel to expel it. Since air is less dense than water, it accumulates inside the steel pipe. As water is added, the gas gathers at the top of the pipe, necessitating an exhaust pipe to guide the air out from the top. The required exhaust pipe length varies depending on the pipe diameter, and must be adjusted when changing pipe specifications. However, in fully automatic hydrostatic testing, the exhaust pipe cannot be manually replaced or adjusted, significantly reducing testing efficiency. Patent ZL2019 2 2067540.2 uses a float-type structure, automatically extending and retracting based on water level to adjust the exhaust pipe length. However, this design is limited by space constraints, restricting the buoyancy and limiting the travel of the telescopic sleeve. This approach cannot accommodate a wider range of pipe sizes. Summary of the Invention

[0004] In order to solve the problem of controllable exhaust pipe of steel pipe hydraulic test machine, the present invention provides an active telescopic exhaust pipe for steel pipe hydraulic test machine.

[0005] The present invention adopts the following technical solution:

[0006] An active telescopic exhaust pipe for a steel pipe hydrostatic testing machine includes a horizontally interconnected left frame and a right frame. A water filling valve and an exhaust valve are installed on the outer side of the left frame. An end seat is installed on the inner side of the left frame, and a multi-section telescopic sleeve is installed on the end seat. The multi-section telescopic sleeve is hydraulically driven to extend and retract. The telescopic sleeve includes a primary sleeve, an intermediate sleeve, and a final sleeve. The primary sleeve has the smallest diameter and is fixed to the end seat opening with connecting feet. The intermediate sleeve includes an intermediate outer sleeve and an intermediate inner sleeve, which are coaxially sleeved to form a closed intermediate annular cavity. The inner annular wall of the intermediate outer sleeve and the outer annular wall of the intermediate inner sleeve at the entrance of the intermediate annular cavity are respectively provided with… The intermediate annular cavity has a limiting platform and a sealing groove. The lower opening of the intermediate annular cavity is adapted to accommodate the entry of the primary annular body. The final stage sleeve is composed of a final stage outer cylinder and a final stage inner cylinder coaxially fitted together. The final stage outer cylinder and the final stage inner cylinder are fitted together to form a final stage annular cavity with a closed upper end. The lower opening of the final stage annular cavity is adapted to accommodate the entry of the intermediate stage sleeve. The inner annular wall of the final stage outer cylinder and the outer annular wall of the final stage inner cylinder at the entrance of the final stage annular cavity are respectively provided with limiting platforms and sealing grooves. Each sealing groove is provided with a seal. The primary annular body is provided with a wall channel for external pressure input. The upper end of the wall channel is connected to the intermediate annular cavity. The upper end of the intermediate stage sleeve is provided with an oil passage connecting the final stage annular cavity and the intermediate annular cavity. The upper end of the final stage inner cylinder is provided with a gas guide hole for the inner ring.

[0007] The primary cylinder entering the intermediate annular cavity is provided with a boss. When the primary cylinder extends out of the intermediate annular cavity by axial displacement, it is matched and limited by the limiting platform provided at the entrance of the intermediate annular cavity. The intermediate sleeve entering the final annular cavity is provided with a boss. When the intermediate sleeve extends out of the final annular cavity by axial displacement, it is matched and limited by the limiting platform provided at the entrance of the final annular cavity.

[0008] A flexible hose is connected to the lower end of the wall channel, and a pressure input port is provided on the end seat for connecting the flexible hose.

[0009] A pull rope sensor is also installed at the connection foot of the primary cylinder, and the pull rope end of the pull rope sensor is fixed to the body of the final stage sleeve.

[0010] The intermediate stage sleeve is a single intermediate stage sleeve or a multi-stage ring-type intermediate stage sleeve.

[0011] The intermediate stage outer cylinder and intermediate stage inner cylinder are fitted together and fixed with screws; the final stage outer cylinder and final stage inner cylinder are fitted together and fixed with screws, and grooves and seals are provided at the fitting joints.

[0012] The sealing grooves on the inner and outer ring walls of the intermediate stage outer cylinder are adjacent upper and lower sealing grooves. The upper sealing groove near the middle ring cylinder cavity is provided with a first outer ring positive seal and a first inner ring positive seal with the lip facing inward. The lower sealing groove is provided with a first outer ring reverse seal and a first inner ring reverse seal with the lip facing outward. The sealing grooves on the inner and outer ring walls of the final stage outer cylinder are adjacent upper and lower sealing grooves. The upper sealing groove near the final stage ring cylinder cavity is provided with a second outer ring positive seal and a second inner ring positive seal with the lip facing inward. The lower sealing groove is provided with a second outer ring reverse seal and a second inner ring reverse seal with the lip facing outward.

[0013] A rubber jacking pipe is also vulcanized at the upper end of the final stage inner cylinder. The rubber jacking pipe is coaxially and closedly connected with the air guide hole. The top of the rubber jacking pipe is an arc shape with a notch.

[0014] Compared with the prior art, the present invention can achieve the following technical effects: the hydraulic control actively extends and retracts the air guide, which overcomes the disadvantage of the difficulty in controlling floating and lifting. The air guide cylinder is not affected by the water level, the hydraulic lifting balance is good, the air guide pipe is not affected by floating and its offset is not affected, and the displacement sensor can be easily installed to monitor the lifting.

[0015] This invention enables the hydraulic press to actively extend and retract to release air, which is highly controllable, safe, efficient, and has improved position sensing capabilities while being small in size. Attached Figure Description

[0016] Figure 1 This is a diagram showing the device structure and installation of the present invention;

[0017] Figure 2 This is a schematic diagram of the retracted state of the telescopic sleeve 3 of the present invention;

[0018] Figure 3 This is a schematic diagram of the telescopic sleeve 3 of the present invention in the raised state;

[0019] Figure 4 This is the present invention. Figure 2 AA magnified image.

[0020] Among them, 1-left frame, 2-end seat, 3-telescopic sleeve, 4-tested steel pipe, 5-right frame, 6-primary cylinder, 7-intermediate stage outer cylinder, 8-intermediate stage inner cylinder, 9-final stage outer cylinder, 10-final stage inner cylinder, 11-wall channel, 12-hose, 13-first outer ring reverse seal, 14-first inner ring reverse seal, 15-first inner ring forward seal, 16-first outer ring forward seal, 17-intermediate annular cylinder cavity, 18-oil passage, 19-final stage annular cylinder cavity, 20-screw one, 21-O-ring, 22-screw two, 23-pull rope sensor, 24-pull rope fixing point, 25-exhaust valve, 26-water filling valve, 27-rubber jacking pipe, 28-vent hole, 29-second outer ring reverse seal, 30-second inner ring reverse seal, 31-second inner ring forward seal, 32-second outer ring forward seal. Detailed Implementation

[0021] like Figure 1-4 As shown, the technical solution adopted by the present invention is as follows: An active telescopic exhaust pipe for a steel pipe hydrostatic testing machine is provided. This active telescopic exhaust pipe is installed at the exhaust end of the left frame 1 of the hydrostatic testing machine. Its structure is a telescopic sleeve 3 with a central axis, which is a segmented structure. The central axis allows for air conduction. The telescopic sleeve 3 is composed of a primary sleeve 6, intermediate sleeves, and a final sleeve connected together. The diameter of each of the three sleeves is larger than the previous one. The primary sleeve 6 has the smallest diameter and is equipped with a connecting foot. The bottom end of the primary sleeve 6 is fixed to the upper hole end of the end seat 2 by bolts connecting the foot. The intermediate sleeve is composed of an intermediate outer sleeve 7 and an intermediate inner sleeve 8 coaxially fitted together. An inner ring platform is provided at the upper end of the intermediate outer sleeve 7, and a positioning stop is provided on the inner ring platform. A positioning platform is provided at the upper end of the intermediate inner sleeve 8, which is adapted to the positioning stop of the intermediate outer sleeve 7. A screw 20 is provided at the positioning platform to connect and fix the intermediate outer sleeve 7 and the intermediate inner sleeve 8, thereby forming an upper closed intermediate ring cylinder cavity 17. The lower opening of the intermediate annular cavity 17 is adapted to accommodate the entry of the primary cylinder 6. The inner ring wall of the intermediate outer cylinder 7 and the outer ring wall of the intermediate inner cylinder 8 at the entrance of the intermediate annular cavity 17 are respectively provided with limiting platforms and adjacent upper and lower sealing grooves. The upper sealing groove near the intermediate annular cavity 17 is provided with a first outer ring positive seal 16 and a first inner ring positive seal 15 with the lip facing inward, which seals the intermediate annular cavity 17 and prevents its pressure from leaking out. The lower sealing groove is provided with a first outer ring reverse seal 13 and a first inner ring reverse seal 14 with the lip facing outward, which prevents external water pressure from leaking into the intermediate annular cavity 17. The primary cylinder 6 entering the intermediate annular cavity 17 is provided with a boss. When the primary cylinder 6 extends outward in the axial displacement of the intermediate annular cavity 17, it is adapted to the limiting platform provided at the entrance to limit and prevent the primary cylinder 6 from slipping out of the intermediate annular cavity 17. When the primary cylinder 6 retracts in the axial displacement of the intermediate annular cavity 17, it is limited by the inner ring platform provided at the upper end of the intermediate outer cylinder 7.

[0022] The final-stage sleeve is composed of a final-stage outer cylinder 9 and a final-stage inner cylinder 10 coaxially fitted together. An inner ring platform is provided at the upper end of the final-stage outer cylinder 9, with a positioning stop and a sealing groove. A positioning platform is provided on the upper outer ring of the final-stage inner cylinder 10, which is adapted to the positioning stop of the final-stage outer cylinder 9. Screws 22 are used at the positioning platform to connect and fix the final-stage outer cylinder 9 and the final-stage inner cylinder 10, thus forming a closed final-stage annular cavity 19. An O-ring 21 is provided in the sealing groove to prevent pressure leakage from the final-stage annular cavity 19. The lower opening of the final-stage annular cavity 19 is adapted to accommodate the intermediate-stage sleeve body. Limiting platforms and adjacent upper and lower sealing grooves are respectively provided on the inner ring wall of the final-stage outer cylinder 9 and the outer ring wall of the final-stage inner cylinder 10 at the entrance of the final-stage annular cavity 19. A second outer ring positive seal 32 and a second inner ring positive seal 31 with inward-facing lips are provided in the upper sealing groove near the final-stage annular cavity 19. To seal the final stage annular cavity 19 and prevent pressure leakage, the lower sealing groove is equipped with a second outer ring reverse seal 29 with the lip facing outward and a second inner ring reverse seal 30 to prevent external water pressure from leaking into the final stage annular cavity 19. The intermediate stage sleeve entering the final stage annular cavity 19 is equipped with a boss. When the intermediate stage sleeve extends axially in the final stage annular cavity 19, it is matched and limited by the limiting platform set at the inlet to prevent the intermediate stage sleeve from slipping out of the final stage annular cavity 19. When the intermediate stage sleeve retracts axially in the final stage annular cavity 19, it is limited by the inner ring platform set at the upper end of the final stage outer cylinder 9. The upper end of the final stage inner cylinder 10 is provided with an air guide hole in the inner ring. The upper end of the final stage inner cylinder 10 is also vulcanized with a rubber jacking pipe 27. The rubber jacking pipe 27 is coaxially closed and connected with the air guide hole. The top end of the rubber jacking pipe 27 is an arc shape with a notch, which is conducive to the discharge of more gas from the top of the tested steel pipe 4.

[0023] An oil passage 18 is provided on the inner ring platform at the upper end of the intermediate stage outer cylinder 7 to connect the final stage ring cylinder cavity 19 and the intermediate ring cylinder cavity 17.

[0024] like Figure 3-4 The primary cylinder 6 is provided with a wall channel 11 for external pressure input. The upper end of the wall channel 11 is connected to the intermediate annular cylinder cavity 17, and the lower end is connected to the hose 12. The end seat 2 is provided with a pressure input port and connected to the hose 12. When pressure is input, the pressure medium enters the intermediate annular cylinder cavity 17 and the final annular cylinder cavity 19, and the gas-conducting telescopic sleeve 3 rises. When the pressure is released, the telescopic sleeve 3 descends. The beneficial effect of the sleeve installation method where the coarser sleeve is higher than the finer sleeve is to increase the upper load weight, which is conducive to achieving stable and rapid descent and reset.

[0025] The telescopic sleeve 3, with its segmented structure, is based on the intermediate-stage sleeve structure. A single intermediate-stage sleeve can be adapted to be composed of multiple intermediate-stage sleeves of different diameters that are nested together, thereby meeting the air guiding requirements at different heights.

[0026] like Figure 3-4A pull rope sensor 23 is also installed at the connection foot of the primary cylinder 6, with its pull rope end fixed to the pull rope fixing point 24 outside the final sleeve body, so as to realize precise control and measurement of displacement.

[0027] The segmented structure of the telescopic sleeve 3 used for exhaust has been shown and described, highlighting the key technical points of the present invention. For those skilled in the art, it will be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. For example, in the embodiment, the hierarchical structure is three-stage, and an intermediate sleeve is added to make it four-stage, and so on. By adding multiple intermediate sleeves, the multi-stage structure can be changed. The purpose is to achieve telescopic exhaust through the multi-stage structure. The specific structure will not be described in detail here.

[0028] The working method is as follows:

[0029] like Figure 1-2 The active telescopic exhaust pipe is installed at the exhaust end of the left frame 1 of the hydraulic pressure testing machine, and the right frame 5 is equipped with the clamping and sealing mechanism of the test steel pipe 4. When the test steel pipe 4 is tested, the test steel pipe 4 is first filled with low-pressure water. During this process, the water filling valve 26 is opened, and low-pressure water is poured into the test steel pipe 4. The exhaust valve 25 is opened, and the air inside the test steel pipe 4 enters the end seat 2 through the internal channel of the telescopic sleeve 3 and is discharged from the exhaust valve 25 through the vent hole 28.

[0030] like Figure 2-4 During water injection and venting, the telescopic sleeve 3 rises, and pressure is input through the pressure inlet on the end seat 2. The pressure medium enters the intermediate annular cavity 17 and the final annular cavity 19 through the hose 12 and wall channel 11. Pressure is established, and the gas-conducting telescopic sleeve 3 rises. The rubber jack 27 presses against the top of the inner cavity of the tested steel pipe 4, which facilitates gas venting. When the pressure inlet is depressurized or under negative pressure, the telescopic sleeve 3 descends by its own weight. Simultaneously, when the tested steel pipe 4 is filled with water, the increased pressure inside the pipe also promotes the descent of the telescopic sleeve 3, thereby quickly releasing the pressure inside the intermediate annular cavity 17 and the final annular cavity 19. Water is allowed to enter the telescopic sleeve 3. The medium filled in the intermediate annular cavity 17 and the final annular cavity 19 of the telescopic sleeve 3 can be oil or water, preferably oil. When the medium is oil, the first outer ring reverse seal 13 and the first inner ring reverse seal 14 prevent water or air pressure in the inner cavity of the tested steel pipe 4 from entering the intermediate annular cavity 17, causing leakage, pressure loss, or contamination; the second outer ring reverse seal 29 and the second inner ring reverse seal 30 prevent water or air pressure in the inner cavity of the tested steel pipe 4 from entering the final annular cavity 19, causing leakage, pressure loss, or contamination; the first inner ring forward seal 15 and the first outer ring forward seal 16 prevent oil / water in the intermediate annular cavity 17 from entering the tested steel pipe 4, causing leakage; the second inner ring forward seal 31 and the second outer ring forward seal 32 prevent oil / water in the final annular cavity 19 from entering the tested steel pipe 4, causing leakage.

[0031] While the test steel pipe 4 is being pressurized, the telescopic sleeve 3 can be extended or retracted by supplying high / low pressure.

[0032] The raising / lowering of the telescopic sleeve 3, along with the raising / lowering of the pull rope end of the traction rope sensor 23, enables the detection of the telescopic sleeve 3 reaching a higher position.

Claims

1. An active telescopic exhaust pipe for a steel pipe hydrostatic testing machine, comprising a left frame (1) and a right frame (5) horizontally connected to each other, wherein a water filling valve (26) and an exhaust valve (25) are provided on the outer side of the left frame (1), and an end seat (2) is provided on the inner side of the left frame (1), wherein a multi-section telescopic sleeve (3) is provided on the end seat (2), characterized in that: The multi-section telescopic sleeve (3) is hydraulically driven to extend and retract. The telescopic sleeve (3) includes a primary sleeve (6), an intermediate sleeve, and a final sleeve. The primary sleeve (6) has the smallest sleeve diameter and is fixed to the end seat (2) with connecting feet. The intermediate sleeve includes an intermediate outer sleeve (7) and an intermediate inner sleeve (8). The intermediate outer sleeve (7) and the intermediate inner sleeve (8) are coaxially sleeved to form an upper closed intermediate annular cavity (17). The inner annular wall of the intermediate outer sleeve (7) and the outer annular wall of the intermediate inner sleeve (8) at the entrance of the intermediate annular cavity (17) are respectively provided with a limiting platform and a sealing groove. The lower opening of the intermediate annular cavity (17) is adapted to accommodate the primary sleeve. The final sleeve consists of a final outer sleeve (9) and a final inner sleeve (9). The cylinder (10) is coaxially fitted together. The final stage outer cylinder (9) and the final stage inner cylinder (10) are fitted together to form a final stage annular cavity (19) with the upper end closed. The lower end of the final stage annular cavity (19) is open to accommodate the intermediate stage sleeve body. The inner annular wall of the final stage outer cylinder (9) and the outer annular wall of the final stage inner cylinder (10) at the entrance of the final stage annular cavity (19) are respectively provided with a limiting platform and a sealing groove. Each sealing groove is respectively provided with a seal. The primary cylinder is provided with a wall channel (11) for external pressure input. The upper end of the wall channel (11) is connected to the intermediate annular cavity (17). The upper end of the intermediate stage sleeve is provided with an oil passage (18) to communicate between the final stage annular cavity (19) and the intermediate annular cavity (17). The upper end of the final stage inner cylinder (10) is provided with a gas guide hole to the inner ring. A pull rope sensor (23) is also provided at the connection foot of the primary cylinder (6), and the pull rope end of the pull rope sensor (23) is fixed to the body of the final sleeve. The upper end of the final inner cylinder (10) is also vulcanized with a rubber jacking pipe (27). The rubber jacking pipe (27) is coaxially closed and connected with the air guide hole. The top end of the rubber jacking pipe (27) is an arc shape with a notch.

2. The active telescopic exhaust pipe of a steel pipe hydrostatic testing machine according to claim 1, characterized in that: The primary cylinder (6) that enters the intermediate annular cavity (17) is provided with a boss. When the primary cylinder (6) extends out of the intermediate annular cavity (17) by axial displacement, it is adapted to and limited by the limiting platform provided at the entrance of the intermediate annular cavity (17). The intermediate sleeve that enters the final annular cavity (19) is provided with a boss. When the intermediate sleeve extends out of the final annular cavity (19) by axial displacement, it is adapted to and limited by the limiting platform provided at the entrance of the final annular cavity (19).

3. The active telescopic exhaust pipe of a steel pipe hydrostatic testing machine according to claim 1, characterized in that: The lower end of the wall channel (11) is connected to a hose (12), and the end seat (2) is provided with a pressure input port connected to the hose (12).

4. The active telescopic exhaust pipe of a steel pipe hydrostatic testing machine according to claim 1, characterized in that: The intermediate sleeve is a single intermediate sleeve or a multi-ring intermediate sleeve.

5. The active telescopic exhaust pipe of a steel pipe hydrostatic testing machine according to claim 1, characterized in that: The intermediate stage outer cylinder (7) and intermediate stage inner cylinder (8) are fitted together and fixed with screws; the final stage outer cylinder (9) and final stage inner cylinder (10) are fitted together and fixed with screws, and grooves and seals are provided at the fitting joint.

6. The active telescopic exhaust pipe of a steel pipe hydrostatic testing machine according to claim 1, characterized in that: The sealing grooves provided on the inner ring wall of the intermediate stage outer cylinder (7) and the outer ring wall of the intermediate stage inner cylinder (8) are two adjacent upper and lower sealing grooves. The upper sealing groove near the cavity of the intermediate ring cylinder (17) is provided with a first outer ring positive seal (16) and a first inner ring positive seal (15) with the lip facing inward. The lower sealing groove is provided with a first outer ring reverse seal (13) and a first inner ring reverse seal (14) with the lip facing outward. The sealing grooves provided on the inner ring wall of the final stage outer cylinder (9) and the outer ring wall of the final stage inner cylinder (10) are two adjacent upper and lower sealing grooves. The upper sealing groove near the cavity of the final stage ring cylinder (19) is provided with a second outer ring positive seal (32) and a second inner ring positive seal (31) with the lip facing inward. The lower sealing groove is provided with a second outer ring reverse seal (29) and a second inner ring reverse seal (30) with the lip facing outward.

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