A method for testing the spring rate of a bellows and apparatus therefor

Abstract

The present application belongs to the technical field of pipeline resilience detection, and particularly relates to a method for testing the resilience of a corrugated pipe and a device thereof, the device comprising a base and a frame-shaped support seat fixed on the upper surface of the base, the side wall of the frame-shaped support seat being fixed with a controller, further comprising two side plates fixed on the top of the frame-shaped support seat on both sides, a clamping plate being arranged between the two side plates, a detachable mounting ring being mounted on the side wall of the side of the clamping plate and one of the side plates, and a compression adjusting mechanism being mounted on the side wall of the clamping plate. The present application can automatically complete the reciprocating compression test of the corrugated pipe, accurately calculate the resilience, make the test result more in line with the actual situation, be flexible to use, have a large test range, reduce the error caused by temperature on the test, and simultaneously detect the air tightness of the corrugated pipe, avoid the problem of inconsistent working conditions and data disconnection, and one-time verify the elastic recovery capability and sealing reliability.

Description

Technical Field

[0001] This invention belongs to the field of pipeline springback testing technology, and in particular relates to a method and apparatus for testing the springback rate of corrugated pipes. Background Technology

[0002] Corrugated pipes are widely used in automotive exhaust systems, chemical pipelines, hydraulic systems, and other fields due to their advantages such as elastic deformation to compensate for displacement, vibration reduction, and sealing. Their resilience rate directly determines their stability and lifespan, and accurate testing is the key to ensuring product performance.

[0003] Currently, when conducting springback rate tests on bellows, several sections of bellows are typically cut and then sequentially installed in a fixture. The fixture is then used to test the bellows, as illustrated by a tension-compression test fixture for coupler bellows disclosed in patent publication number CN218674509U. Existing bellows springback rate tests often employ a long-term stable pressure application followed by releasing the fixture, and then calculating the springback length to obtain the result. However, in actual applications, the stress on bellows is not a single stable state. For example, the turbulence generated during fluid transport in chemical pipelines can subject them to high-frequency alternating pressure impacts. This long-term stable pressure test cannot simulate real reciprocating working conditions and is difficult to reflect the springback attenuation law, fatigue damage, and long-term reliability of bellows under high-frequency cyclic loads. Consequently, the test results do not match the actual results and cannot provide accurate support for the safe use of products. Summary of the Invention

[0004] The purpose of this invention is to address the above-mentioned problems by providing a method and apparatus for testing the resilience of bellows.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a device for testing the resilience of bellows, comprising a base and a frame-shaped support fixed to the upper surface of the base, wherein a controller is fixed to the side wall of the frame-shaped support, and further comprising:

[0006] Two side plates are fixed to the top two sides of the frame support base respectively. A clamping plate is provided between the two side plates. A detachable mounting ring is installed on the side wall of the clamping plate and one of the side plates facing each other. A compression adjustment mechanism is installed on the side wall of the clamping plate.

[0007] A drive unit is installed inside the frame-shaped support base, and the drive unit is used to drive the clamping plate to move;

[0008] The temperature control unit is located above the frame support base, and the side plate and clamping plate are both located inside the temperature control unit.

[0009] Preferably, the compression adjustment mechanism includes an electric push rod fixedly inserted into the side wall of the clamping plate. The movable end of the electric push rod is located on the side of the clamping plate away from the mounting ring, and an adjustment plate is fixed to the movable end of the electric push rod. The electric push rod is electrically connected to the controller.

[0010] Preferably, a plurality of detachable side stops are installed between the two side plates, and the side walls of the adjusting plate and the clamping plate are provided with clearance grooves that match the side stops, and the side stops slide through the corresponding clearance grooves.

[0011] Preferably, the drive unit includes mounting seats fixed on both sides inside the frame support base, a chain drive assembly is installed between the two mounting seats, and a drive bar is fixed on the outer surface of the chain of the chain drive assembly. A set of stop bars is fixed on the upper surface of the drive bar, and the top of the stop bars is higher than the bottom of the adjusting plate. The chain drive assembly is electrically connected to the controller. Guide wheel assemblies are fixed on both side walls of the clamping plate, and a support guide rail matching the guide wheel assembly is fixed on the top of the mounting seat.

[0012] Preferably, an infrared ranging probe is fixed to the side wall of the side plate away from the mounting ring, and the infrared ranging probe is used to detect the position of the adjustment plate. Two proximity switches for detecting the position of the drive bar are fixed to the side wall of one of the mounting bases, and the proximity switches are respectively set on the upper side of the head end and the tail end of the chain drive assembly. The controller controls the infrared ranging probe to work according to the electrical signal fed back by the proximity switches.

[0013] Preferably, the temperature control unit includes hydraulic cylinders fixedly inserted at the four corners of the base end face, and the movable ends of the four hydraulic cylinders are jointly fixed with a heat insulation cover. The side plates and clamping plates are all located inside the heat insulation cover. An air pump, a heater, and a cooler are fixed on the inner wall of the frame-shaped support. An air intake tee is fixed to the suction end of the air pump. The two suction ends of the air intake tee are respectively connected to the interior of the heater and the cooler. An electric control valve is installed inside the two suction ends of the air intake tee. A temperature measuring component is installed at the air inlet ends of the heater and the cooler. An exhaust pipe located inside the heat insulation cover is fixedly connected to the air outlet end of the air pump. An air tightness detection component is installed on the exhaust pipe. The air pump, heater, cooler, and electric control valve are all electrically connected to the controller.

[0014] Preferably, the temperature measuring component includes an air inlet tee pipe disposed inside the frame support base, and the two air outlets of the air inlet tee pipe are respectively connected to the interior of the heater and the cooler. The air inlet end of the air inlet tee pipe is fixedly connected to a temperature measuring box, and the side wall of the temperature measuring box is provided with an air inlet hole. The temperature measuring box is fixedly equipped with a temperature probe electrically connected to the controller.

[0015] Preferably, the airtightness detection component includes a diverter pipe fixedly connected to the wall of the exhaust pipe, the diverter pipe being fixedly connected to a pressure measuring box, and a pressure measuring probe electrically connected to the controller being installed inside the pressure measuring box. The pressure measuring box is fixedly connected to a pressure measuring tube coaxial with the mounting ring, and the outlet end of the pressure measuring tube passes through a side plate on the same side. A normally closed solenoid valve is fixed inside the diverter pipe, and a normally open solenoid valve is fixed inside the exhaust pipe at a position above the diverter pipe. Both the normally closed and normally open solenoid valves are electrically connected to the controller.

[0016] A method for testing the springback rate of a bellows, which uses the apparatus for testing the springback rate of a bellows as described above, includes the following steps:

[0017] Step 1: Prepare the bellows to be tested and the testing device for testing the resilience of the bellows;

[0018] Step 2: Fix the corrugated pipe to be tested using the clamping structure of the testing device to ensure that the corrugated pipe is installed stably and in a naturally extended state;

[0019] Step 3: Activate the temperature control function of the testing device, detect the current test environment temperature, and adjust the test environment temperature to the set temperature range based on the detected temperature.

[0020] Step 4: Activate the position detection function of the test device and record the initial reference position of the bellows under test in its natural extended state. Then, activate the reciprocating compression drive function to drive one end of the bellows to move to the other end to achieve compression. When the bellows is compressed to the preset stroke, record the compression limit position of the bellows at this time. Then, release the driving force to allow the bellows to rebound under its own elasticity. After the rebound stabilizes, record the rebound recovery position of the bellows. Repeat the compression and rebound action to complete the reciprocating compression test for a preset number of times, and record the compression limit position and rebound recovery position of the bellows each time.

[0021] Step 5: Based on the initial reference position, compression limit position and springback recovery position recorded in Step 4, and combined with the pre-calibrated system error correction value, calculate the springback rate of the bellows.

[0022] Preferably, in step four, after the bellows has recovered from its compressed state, a fixed amount of gas is introduced into the bellows, and the sealing performance of the bellows is determined based on the gas pressure value.

[0023] Compared with existing technologies, the advantages of a method and apparatus for testing the resilience of bellows are:

[0024] 1. Through the testing methods in steps one through five, the instantaneous and high-frequency compressive forces encountered by the bellows during actual use can be simulated through reciprocating compression, making the test results more realistic. Furthermore, with the cooperation of the base, frame support, controller, side plate, clamping plate, mounting ring, and drive unit in the testing device, the bellows can be reciprocated after clamping and installation. Combined with the infrared ranging probe and proximity switch, the length of the bellows during the reciprocating compression process can be automatically recorded, allowing for the calculation of the bellows' rebound rate. Using reciprocating compression, not only can continuous and stable pressure testing be performed, but the instantaneous and high-frequency compressive forces encountered by the bellows during actual use can also be simulated, improving the flexibility of the testing device.

[0025] 2. The compression adjustment mechanism can be flexibly adjusted according to different bellows compression requirements, while the temperature control unit can ensure that the bellows is tested at a stable temperature before and during the test, reducing the impact of temperature on the bellows rebound rate test error.

[0026] 3. By using the airtightness testing component, the air source of the temperature control unit can be used to test the airtightness of the bellows. This not only tests the rebound rate of the bellows, but also simultaneously detects the airtightness of the bellows, avoiding the problems of inconsistent working conditions and data disconnect caused by traditional separate testing. It verifies the elastic recovery ability and sealing reliability of the bellows in one go. Attached Figure Description

[0027] Figure 1 This is a flowchart of a method for testing the springback rate of a bellows provided by the present invention;

[0028] Figure 2 This is a three-dimensional structural schematic diagram of a device for testing the resilience of bellows provided by the present invention;

[0029] Figure 3 This is a schematic diagram of the internal structure of the heat insulation cover of a device for testing the resilience of bellows provided by the present invention.

[0030] Figure 4 This is a schematic diagram of the back structure of a frame support base for a device for testing the resilience of bellows provided by the present invention.

[0031] Figure 5 This is a schematic diagram of the connection structure between the side plate and the clamping plate of a device for testing the resilience of a bellows provided by the present invention.

[0032] Figure 6 This is a schematic diagram of the internal structure of a frame-shaped support base for a device used to test the resilience of bellows, provided by the present invention.

[0033] Figure 7 This invention provides a device for testing the springback rate of bellows. Figure 6 Enlarged view of the structure of section A;

[0034] Figure 8 This invention provides a device for testing the springback rate of bellows. Figure 3 Enlarged view of the structure of section B.

[0035] In the diagram: 1. Base; 2. Frame-shaped support; 3. Controller; 4. Side plate; 5. Clamping plate; 6. Mounting ring; 7. Compression adjustment mechanism; 71. Electric push rod; 72. Adjustment plate; 8. Drive unit; 81. Mounting base; 82. Chain drive assembly; 83. Drive bar; 84. Stop bar; 9. Temperature control unit; 91. Hydraulic cylinder; 92. Insulation cover; 93. Air pump; 94. Heater; 95. Refrigerator; 96. Suction tee; 97. 98. Electric control valve; 10. Exhaust pipe; 11. Side baffle; 12. Guide rail wheel assembly; 13. Support guide rail; 14. Temperature measuring assembly; 15. Intake tee pipe; 16. Temperature measuring box; 17. Temperature probe; 18. Air tightness detection assembly; 19. Diverter pipe; 10. Pressure measuring box; 11. Pressure measuring probe; 12. Pressure measuring tube; 13. Normally closed solenoid valve; 14. Normally open solenoid valve; 15. Infrared ranging probe; 16. Proximity switch. Detailed Implementation

[0036] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0037] like Figure 1 As shown, a method for testing the springback rate of a bellows includes the following steps:

[0038] Step 1: Prepare the bellows to be tested and the testing device for testing the resilience of the bellows;

[0039] Step 2: Fix the corrugated pipe to be tested using the clamping structure of the testing device to ensure that the corrugated pipe is installed stably and in a naturally extended state;

[0040] Step 3: Activate the temperature control function of the testing device, detect the current test environment temperature, and adjust the test environment temperature to the set temperature range based on the detected temperature.

[0041] Step 4: Activate the position detection function of the test device and record the initial reference position of the bellows under test in its natural extended state. Then, activate the reciprocating compression drive function to drive one end of the bellows to move to the other end to achieve compression. When the bellows is compressed to the preset stroke, record the compression limit position of the bellows at this time. Then, release the driving force to allow the bellows to rebound under its own elasticity. After the rebound stabilizes, record the rebound recovery position of the bellows. Repeat the compression and rebound action to complete the preset number of reciprocating compression tests. Simultaneously record the compression limit position and rebound recovery position of the bellows each time. According to the test requirements, after the bellows rebounds from the compressed state, a certain amount of gas can be injected into the bellows, and the sealing performance of the bellows can be judged based on the gas pressure value.

[0042] Step 5: Based on the initial reference position, compression limit position and springback recovery position recorded in Step 4, and combined with the pre-calibrated system error correction value, calculate the springback rate of the bellows.

[0043] like Figure 2-8 As shown, a device for testing the rebound rate of a bellows includes a base 1 and a frame-shaped support 2 fixed to the upper surface of the base 1. A controller 3 is fixed to the side wall of the frame-shaped support 2. The device also includes two side plates 4, which are respectively fixed to the top two sides of the frame-shaped support 2. A clamping plate 5 is provided between the two side plates 4. A detachable mounting ring 6 is installed on the side wall of the clamping plate 5 and one of the side plates 4 facing each other. A compression adjustment mechanism 7 is installed on the side wall of the clamping plate 5. The compression adjustment mechanism 7 includes an electric push rod 71 fixedly inserted into the side wall of the clamping plate 5. The movable end of the electric push rod 71 is located on the side of the clamping plate 5 away from the mounting ring 6, and an adjustment plate 72 is fixed to the movable end of the electric push rod 71. The electric push rod 71 is electrically connected to the controller 3. The housings of the adjustment plate 72, the electric push rod 71, and the clamping plate 5 are all made of lightweight materials to minimize the impact of movement resistance on the rebound of the bellows.

[0044] Multiple detachable side stops 10 are installed between the two side plates 4. The side walls of the adjusting plate 72 and the clamping plate 5 are provided with clearance grooves that match the side stops 10, and the side stops 10 slide through the corresponding clearance grooves.

[0045] The drive unit 8 is installed inside the frame support 2 and is used to drive the clamping plate 5 to move. The drive unit 8 includes mounting seats 81 fixed on both sides inside the frame support 2. A chain drive assembly 82 is installed between the two mounting seats 81. A drive bar 83 is fixed on the outer surface of the chain of the chain drive assembly 82. A set of stop bars 84 is fixed on the upper surface of the drive bar 83. The top of the stop bars 84 is higher than the bottom of the adjusting plate 72. The chain drive assembly 82 is electrically connected to the controller 3. The chain drive assembly 82 includes components such as sprockets, bearings, drive shafts, chains, and motors.

[0046] The clamping plate 5 is fixed with guide wheel assemblies 11 on both side walls. The top of the mounting base 81 is fixed with a support guide rail 12 that matches the guide wheel assembly 11. The guide wheel assembly 11 and the support guide rail 12 can ensure stable support for the clamping plate 5 and minimize the friction force when the clamping plate 5 moves.

[0047] The temperature control unit 9 is located above the frame-shaped support base 2. The side plates 4 and clamping plates 5 are both located inside the temperature control unit 9. The temperature control unit 9 includes hydraulic cylinders 91 fixedly inserted into the four corners of the end face of the base 1, and the movable ends of the four hydraulic cylinders 91 are jointly fixed with a heat insulation cover 92. The side plates 4 and clamping plates 5 are both located inside the heat insulation cover 92. An air pump 93, a heater 94, and a cooler 95 are fixed to the inner wall of the frame-shaped support base 2. An air intake tee 96 is fixed to the suction end of the air pump 93, and the two suction ends of the air intake tee 96 are respectively... The air pump 93 is not connected to the heater 94 and the cooler 95. Both intake ends of the air intake tee 96 are equipped with an electric control valve 97. The exhaust end of the air pump 93 is fixedly connected to the exhaust pipe 98 located inside the heat insulation cover 92. The air pump 93, heater 94, cooler 95 and electric control valve 97 are all electrically connected to the controller 3. The heater 94 uses an electric heating plate for heating. The cooler 95 uses a semiconductor refrigeration device. The heat dissipation end of the semiconductor refrigeration device is located on the outside of the frame support 2, and a cooling fan is installed on the heat dissipation end.

[0048] A temperature measuring component 13 is installed at the air inlet of both the heater 94 and the cooler 95. The temperature measuring component 13 includes an air inlet tee pipe 131 located inside the frame support 2. The two air outlets of the air inlet tee pipe 131 are respectively connected to the interior of the heater 94 and the cooler 95. A temperature measuring box 132 is fixedly connected to the air inlet of the air inlet tee pipe 131. An air inlet hole is provided on the side wall of the temperature measuring box 132. A temperature probe 133 electrically connected to the controller 3 is fixedly installed in the temperature measuring box 132. The temperature probe 133 can convert the temperature into an electrical signal and feed it back to the controller 3.

[0049] The exhaust pipe 98 is equipped with an airtightness detection component 14. The airtightness detection component 14 includes a diverter pipe 141 fixedly connected to the wall of the exhaust pipe 98. The diverter pipe 141 is fixedly connected to a pressure measuring box 142, and a pressure measuring probe 143 electrically connected to the controller 3 is installed inside the pressure measuring box 142. The pressure measuring box 142 is fixedly connected to a pressure measuring tube 144 coaxial with the mounting ring 6, and the outlet end of the pressure measuring tube 144 passes through the side plate 4 on the same side. A normally closed solenoid valve 145 is fixedly installed inside the diverter pipe 141. A normally open solenoid valve 146 is fixedly installed inside the exhaust pipe 98 at a position above the diverter pipe 141. Both the normally closed solenoid valve 145 and the normally open solenoid valve 146 are electrically connected to the controller 3. The pressure measuring probe 143 can convert the air pressure into an electrical signal and feed it back to the controller 3.

[0050] An infrared ranging probe 15 is fixed to the side wall of the side plate 4 away from the mounting ring 6, and the infrared ranging probe 15 is used to detect the position of the adjustment plate 72. Two proximity switches 16 for detecting the position of the drive bar 83 are fixed to the side wall of one of the mounting bases 81, and the proximity switches 16 are respectively set on the upper side of the head end and the tail end of the chain drive assembly 82. The controller 3 controls the infrared ranging probe 15 to work according to the electrical signal fed back by the proximity switch 16. The proximity switch 16 can immediately feed back an electrical signal to the controller 3 when it detects the drive bar 83 passing by.

[0051] The operating principle of the present invention is explained as follows: Before the test, the uppermost side stop post 10 is removed, and then the two ends of the corrugated pipe to be tested are respectively put on the outside of the corresponding mounting ring 6. Then, clamps such as clamps are used to stably clamp the corrugated pipe on the outside of the two mounting rings 6 and keep the corrugated pipe in a naturally extended state. Then, the side stop post 10 is installed back in its original position, and the controller 3 is started to start the test.

[0052] Controller 3 immediately controls hydraulic cylinder 91 to operate on a timed basis. Hydraulic cylinder 91 drives the insulation cover 92 to move downwards. After hydraulic cylinder 91 stops operating, the bottom of the insulation cover 92 is stably abutted against the top of the frame support 2. Subsequently, controller 3 controls temperature probe 133 to operate. Temperature probe 133 detects the current temperature inside the insulation cover 92. When the temperature is lower than a set threshold (this threshold is set to the standard test temperature of 23℃±0.5℃), controller 3 controls the heater 94 to operate and controls the electric control valve 97 on one side of the heater 94 to open. Conversely, when the temperature is higher than the set threshold, controller 3... The controller 3 controls the operation of the cooler 95 and opens the electric valve 97 on one side of the cooler 95. Then, the controller 3 controls the air pump 93 to operate. The air pump 93 draws in air that has been heated by the heater 94 or cooled by the cooler 95 through the air intake three-way pipe 96 and discharges it through the exhaust pipe 98. The operation of the air pump 93 can make the air inside the heat insulation cover 92 flow. The flowing air is heated by the heater 94 or cooled by the cooler 95, so that the temperature inside the heat insulation cover 92 is kept near the set threshold. After the temperature probe 133 detects that the temperature has reached the threshold, the controller 3 will immediately start the test operation.

[0053] In the initial stage of the controller 3's start-up test, the controller 3 immediately controls the infrared ranging probe 15 to operate once. The infrared ranging probe 15 emits an infrared beam, which is reflected back to the infrared ranging probe 15 by the adjustment plate 72. The infrared ranging probe 15 can calculate the position of the adjustment plate 72 at this time by calculating the time from the emission of the infrared beam to the receipt of the infrared beam. Meanwhile, the controller 3 controls the chain drive assembly 82 to work according to a preset program. The chain drive assembly 82 drives the drive bar 83 to move. When the drive bar 83 moves the stop bar 84 to the position of the adjustment plate 72, the stop bar 84 will push the adjustment plate 72 to move. The adjustment plate 72 will then drive one end of the bellows to the other end through the electric push rod 71 and the clamping plate 5, thereby enabling the bellows to be adjusted. Compression occurs when the stop lever 84 moves to the tail end of the chain drive assembly 82. The stop lever 84 rotates from the upper to the lower side of the chain drive assembly 82. At this time, the proximity switch 16 at the tail end of the chain drive assembly 82 detects the passing of the drive bar 83 and immediately sends an electrical signal to the controller 3. The controller 3 then immediately controls the infrared ranging probe 15 to operate once and detects the current position of the adjusting plate 72. This distance represents the compression amount of the bellows length. Simultaneously, the stop lever 84 disengages from the adjusting plate 72 due to rotation, thus eliminating the stop lever 84's resistance to the adjusting plate 72. Under its own elastic expansion and contraction, the bellows immediately pushes the clamping plate 5, causing the adjusting plate 72 to move back. When the stop lever 84 moves to the proximity switch 1 at the head end of the chain drive assembly 82... At position 6, the proximity switch 16 sends an electrical signal to the controller 3. The controller 3 then controls the infrared ranging probe 15 to detect the position of the adjusting plate 72 again. Subsequently, the stop lever 84 continues to move and abuts against the side wall of the adjusting plate 72 again, thereby compressing the bellows again. Through the continuous reciprocating movement of the stop lever 84, the bellows is repeatedly compressed. During the reciprocating compression process, the infrared ranging probe 15 records the position of the adjusting plate 72 sequentially. The rebound rate of the bellows can be calculated based on the position of the adjusting plate 72. However, due to the resistance encountered when the adjusting plate 72, the electric push rod 71, and the clamping plate 5 move, the adjusting plate 72 usually cannot return to its initial position after the initial compression and rebound of the bellows. To avoid errors caused by this phenomenon, a 3 Five corrugated pipes with qualified rebound rates and identical specifications were used as standard parts. Under the same constant temperature environment, compression rate, and fixture conditions, the position of the adjusting plate 72 after initial compression and rebound was measured. The distance difference between the current position of the adjusting plate 72 and its initial original position was calculated and averaged as a system error correction value. During actual testing, the rebound rate of the corrugated pipe was calculated based on this correction value. For example, the difference between the position of the corrugated pipe after compression and the position of the adjusting plate 72 after rebound was first recorded, and then the average distance difference of the standard parts was subtracted. The result was the actual rebound distance of the corrugated pipe, and the rebound rate of the corrugated pipe was finally calculated. (When calculating the rebound rate, the initial original position of the adjusting plate 72 was recorded first, and then the position of the adjusting plate 72 after compression was recorded. The difference between the two is the total length of the corrugated pipe compressed. After the corrugated pipe rebounds...)Record the springback position of the adjusting plate 72. Subtract the average distance difference of the standard parts from the difference between the compressed position and the springback position to obtain the actual springback length of the bellows. Finally, calculate the percentage of the actual springback length to the total compressed length to obtain the springback rate of the bellows.

[0054] The above test is mainly aimed at the rebound rate test of high frequency reciprocating compression bellows. In actual testing, it can also be pre-programmed so that the controller 3 controls the stop lever 84 to stop moving after moving to a certain position, and after a certain period of stable pressure, the stop lever 84 is driven to disengage from the adjustment plate 72, and the position of the adjustment plate 72 after the return is calculated. This method is suitable for long-term stable pressure test and can be selected according to test requirements.

[0055] Simultaneously, during the test, according to the test requirements, the normally closed solenoid valve 145 and the normally open solenoid valve 146 are controlled by the controller 3 through pre-programming. At this time, the air delivered by the air pump 93 will enter the bellows through the pressure measuring box 142 and the pressure measuring tube 144, thereby inflating the bellows. The pressure measuring probe 143 inside the pressure measuring box 142 can detect the air pressure inside the bellows. The pressure measuring probe 143 can convert the air pressure into an electrical signal and feed it back to the controller 3. After the air pressure reaches the threshold (this threshold can be preset based on the type and specifications of the bellows being tested), the pressure measuring probe 143 will send a signal to the controller. 3. When the feedback signal meets the standard, the controller 3 will control the normally closed solenoid valve 145 to close and the normally open solenoid valve 146 to open. After waiting for a certain period of time, the pressure probe 143 will again feed back an electrical signal representing the air pressure to the controller 3. By calculating the difference between the electrical signals before and after, the sealing performance of the bellows after multiple compressions can be reflected. For example, if the bellows has poor pressure resistance, the bellows may experience pipe wall rupture during compression and expansion. At this time, the gas filled in will leak, resulting in a large deviation between the electrical signals fed back to the controller 3 by the pressure probe 143 before and after.

[0056] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A device for testing the resilience of a corrugated pipe, comprising a base (1) and a frame-shaped support seat (2) fixed to the upper surface of the base (1), the side walls of the frame-shaped support seat (2) being fixed with a controller (3), characterized in that, Also includes: Two side plates (4) are fixed on the top two sides of the frame support base (2), and a clamping plate (5) is provided between the two side plates (4). The clamping plate (5) and the side wall of one of the side plates (4) facing each other are equipped with a detachable mounting ring (6). The side wall of the clamping plate (5) is equipped with a compression adjustment mechanism (7). The drive unit (8) is installed inside the frame support (2) and is used to drive the clamping plate (5) to move. Temperature control unit (9) is located above the frame support base (2), and the side plate (4) and clamping plate (5) are both located inside the temperature control unit (9); The compression adjustment mechanism (7) includes an electric push rod (71) fixedly inserted into the side wall of the clamping plate (5). The movable end of the electric push rod (71) is located on the side of the clamping plate (5) away from the mounting ring (6), and the movable end of the electric push rod (71) is fixed with an adjustment plate (72). The electric push rod (71) is electrically connected to the controller (3). The drive unit (8) includes mounting seats (81) fixed on both sides inside the frame support base (2), a chain drive assembly (82) is installed between the two mounting seats (81), and a drive bar (83) is fixed on the outer surface of the chain of the chain drive assembly (82). A set of stop bars (84) is fixed on the upper surface of the drive bar (83), and the top of the stop bars (84) is higher than the bottom of the adjustment plate (72). The chain drive assembly (82) is electrically connected to the controller (3). Guide wheel assemblies (11) are fixed on both side walls of the clamping plate (5), and a support guide rail (12) matching the guide wheel assembly (11) is fixed on the top of the mounting seat (81). An infrared ranging probe (15) is fixed on the side wall of the side plate (4) away from the mounting ring (6), and the infrared ranging probe (15) is used to detect the position of the adjustment plate (72). Two proximity switches (16) for detecting the position of the drive bar (83) are fixed on the side wall of one of the mounting bases (81), and the proximity switches (16) are respectively set on the upper side of the head end and the tail end of the chain drive assembly (82). The controller (3) controls the infrared ranging probe (15) to work according to the electrical signal fed back by the proximity switch (16).

2. A device for testing the spring rate of a bellows according to claim 1, characterized in that Multiple detachable side posts (10) are installed between the two side plates (4). The side walls of the adjusting plate (72) and the clamping plate (5) are provided with relief grooves that match the side posts (10), and the side posts (10) slide through the corresponding relief grooves.

3. A device for testing the spring rate of a bellows according to claim 1, wherein The temperature control unit (9) includes hydraulic cylinders (91) fixedly inserted into the four corners of the end face of the base (1), and the movable ends of the four hydraulic cylinders (91) are jointly fixed with a heat insulation cover (92). The side plate (4) and the clamping plate (5) are both located inside the heat insulation cover (92). The inner wall of the frame support base (2) is fixed with an air pump (93), a heater (94) and a cooler (95). The suction end of the air pump (93) is fixed with a suction tee pipe (96), and the two suction ends of the suction tee pipe (96) are respectively connected to the heater (94). The air pump (93) is connected to the inside of the refrigeration unit (95), and both suction ends of the suction three-way pipe (96) are equipped with electric control valves (97). The air inlet ends of the heater (94) and the refrigeration unit (95) are jointly equipped with temperature measuring components (13). The air outlet end of the air pump (93) is fixedly connected to the exhaust pipe (98) located inside the heat insulation cover (92), and the exhaust pipe (98) is equipped with an airtightness detection component (14). The air pump (93), the heater (94), the refrigeration unit (95) and the electric control valves (97) are all electrically connected to the controller (3).

4. A device for testing the spring rate of a bellows according to claim 3, wherein The temperature measuring component (13) includes an air inlet tee pipe (131) disposed inside the frame support base (2), and the two air outlets of the air inlet tee pipe (131) are respectively connected to the interior of the heater (94) and the cooler (95). The air inlet end of the air inlet tee pipe (131) is fixedly connected to a temperature measuring box (132), and the side wall of the temperature measuring box (132) is provided with an air inlet hole. The temperature measuring box (132) is fixedly equipped with a temperature probe (133) electrically connected to the controller (3).

5. A device for testing the spring rate of a bellows according to claim 3, wherein The airtightness detection component (14) includes a shunt pipe (141) fixedly connected to the wall of the exhaust pipe (98). The shunt pipe (141) is fixedly connected to a pressure measuring box (142), and a pressure measuring probe (143) electrically connected to the controller (3) is installed inside the pressure measuring box (142). The pressure measuring box (142) is fixedly connected to a pressure measuring tube (144) coaxial with the mounting ring (6), and the outlet end of the pressure measuring tube (144) passes through the side plate (4) on the same side. A normally closed solenoid valve (145) is fixed inside the shunt pipe (141), and a normally open solenoid valve (146) is fixed inside the exhaust pipe (98) at a position above the shunt pipe (141). Both the normally closed solenoid valve (145) and the normally open solenoid valve (146) are electrically connected to the controller (3).

6. A method for testing the spring rate of a bellows, which refers to the device for testing the spring rate of a bellows as claimed in claim 1, characterized in that, The method includes the following steps: Step 1: Prepare the bellows to be tested and the testing device for testing the resilience of the bellows; Step 2: Fix the corrugated pipe to be tested using the clamping structure of the testing device to ensure that the corrugated pipe is installed stably and in a naturally extended state; Step 3: Activate the temperature control function of the testing device, detect the current test environment temperature, and adjust the test environment temperature to the set temperature range based on the detected temperature. Step 4: Activate the position detection function of the test device and record the initial reference position of the bellows under test in its natural extended state. Then, activate the reciprocating compression drive function to drive one end of the bellows to move to the other end to achieve compression. When the bellows is compressed to the preset stroke, record the compression limit position of the bellows at this time. Then, release the driving force to allow the bellows to rebound under its own elasticity. After the rebound stabilizes, record the rebound recovery position of the bellows. Repeat the compression and rebound action to complete the reciprocating compression test for a preset number of times, and record the compression limit position and rebound recovery position of the bellows each time. Step 5: Based on the initial reference position, compression limit position and springback recovery position recorded in Step 4, and combined with the pre-calibrated system error correction value, calculate the springback rate of the bellows.

7. A method for testing the spring rate of a bellows according to claim 6, wherein, In step four, after the bellows has recovered from its compressed state, a fixed amount of gas is introduced into the bellows, and the sealing performance of the bellows is judged based on the gas pressure value.

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