CN107917123B - Hydraulic valve fatigue and high pressure resistant test stand - Google Patents
Hydraulic valve fatigue and high pressure resistant test stand Download PDFInfo
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- CN107917123B CN107917123B CN201711380909.4A CN201711380909A CN107917123B CN 107917123 B CN107917123 B CN 107917123B CN 201711380909 A CN201711380909 A CN 201711380909A CN 107917123 B CN107917123 B CN 107917123B
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- 238000012360 testing method Methods 0.000 title claims abstract description 70
- 230000035485 pulse pressure Effects 0.000 claims abstract description 6
- 239000007788 liquid Substances 0.000 claims description 5
- 238000010521 absorption reaction Methods 0.000 claims description 3
- 238000010998 test method Methods 0.000 claims description 3
- 238000000034 method Methods 0.000 claims description 2
- 238000004134 energy conservation Methods 0.000 abstract description 4
- 238000009661 fatigue test Methods 0.000 description 3
- 230000002929 anti-fatigue Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B19/00—Testing; Calibrating; Fault detection or monitoring; Simulation or modelling of fluid-pressure systems or apparatus not otherwise provided for
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B1/00—Installations or systems with accumulators; Supply reservoir or sump assemblies
- F15B1/02—Installations or systems with accumulators
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
- F15B2211/205—Systems with pumps
- F15B2211/20507—Type of prime mover
- F15B2211/20515—Electric motor
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
The invention discloses a hydraulic valve fatigue and high pressure resistance test bed, and relates to the field of hydraulic valve fatigue and high pressure resistance tests. The motor (2) drives the hydraulic pump (1) to provide a power source for the test system. The overflow valve group (4) is used for setting the highest pressure and unloading of the system. The proportional relief valve (6) is used for setting the actual required test pressure. The servo valve (9) can realize high-speed oil circuit switching and is used for controlling the movement direction and speed of the booster cylinder and providing pulse pressure signals and pressurizing signals for the booster cylinder. The pressure cylinder (10) has a pressure amplifying function and generates high-pressure test pressure pulses under the action of a servo valve pulse pressure signal. The pressure sensor b (13) is used for collecting pressure pulse signals and transmitting the pressure pulse signals to the industrial personal computer. The time at which the valve under test is damaged is the pressure life data of the valve. The device is suitable for multi-channel valve cavity fatigue and high pressure resistance tests, and has the advantages of stability, reliability, energy conservation, simplicity and convenience in operation and the like.
Description
Technical Field
The invention relates to the field of hydraulic tests, in particular to the field of fatigue and high pressure resistance tests of hydraulic valves.
Background
The anti-fatigue and high pressure resistant performance of the hydraulic valve is an important technical index of the reliability of the hydraulic valve. The hydraulic valve fatigue and high pressure resistance test bed is mainly used for the fatigue test of a hydraulic valve body and the high pressure resistance test of the hydraulic valve, and is used for testing the high pressure resistance degree and the fatigue failure loading stress of various hydraulic elements by loading alternating high pressure oil liquid on the valve for a long time. The element failure factor and mechanism can be further analyzed, and a basis is provided for the improvement of the element reliability. The testing technique is closely related to the reliability of the hydraulic components. The fatigue and high pressure resistance test of the hydraulic valve has the problems of high pressure, high requirement on energy conservation and reliability, and high-frequency hydraulic pulse to be provided.
Disclosure of Invention
The invention aims to provide a hydraulic valve fatigue and high pressure resistance test bed. The high-frequency hydraulic pulse energy-saving device aims at achieving the purposes of high-frequency hydraulic pulse, energy conservation and high reliability.
In order to achieve the above purpose, the technical scheme adopted by the invention is that the hydraulic valve fatigue and high pressure resistant test stand comprises a hydraulic pump 1, a motor 2, a one-way valve a3, an overflow valve group 4, a pressure gauge a5, a proportional overflow valve 6, a high pressure filter 7, an energy accumulator 8, a servo valve 9, a booster cylinder 10, a one-way valve b11, a pressure gauge b12, a pressure sensor a13, a safety valve 14, a pressure sensor b15, a liquid level meter 16, an oil absorption filter 17, an air filter 18 and a temperature sensor 19.
The hydraulic pump 1 is connected with an oil tank through an oil suction filter 17, and a liquid level meter 16, an air filter 18 and a temperature sensor 19 are arranged in the oil tank;
The hydraulic pump 1 is driven by a motor 2, a hydraulic pipeline enters a parallel valve bank through an oil tank and a one-way valve a3, the parallel valve bank comprises an overflow valve bank 4 and a proportional overflow valve 6, and the overflow valve bank 4 and the proportional overflow valve 6 are arranged in parallel between an oil inlet pipeline and an oil return pipeline; the oil inlet pipeline of the parallel valve group is provided with a pressure gauge a5 and a pressure sensor 15.
The oil inlet pipeline of the parallel valve bank is connected with the booster cylinder 10 after passing through the high-pressure filter 7 and the servo valve 9; the servo valve 9 is connected with the accumulator 8, and a piston oil return port of the booster cylinder 10 is connected with the servo valve 9 through a one-way valve b11 to form a hydraulic circuit; the booster cylinder 10 is connected with a tested valve; a pressure gauge b12 and a pressure sensor a13 are arranged between the booster cylinder 10 and the tested valve, and the pressure sensor a13 is connected with a safety valve 14.
The beneficial effects of the invention are as follows: the device is suitable for multi-channel valve cavity fatigue and high pressure resistance tests, and has the advantages of stability, reliability, energy conservation, simplicity and convenience in operation and the like.
Drawings
Fig. 1 is a block diagram of a hydraulic system of the present invention.
In the figure: 1-hydraulic pump, 2-motor, 3-check valve a, 4-overflow valves, 5-manometer a, 6-proportional overflow valve, 7-high pressure filter, 8-accumulator, 9-servo valve, 10-booster cylinder, 11-check valve b, 12-manometer b, 13-pressure sensor, 14-relief valve, 15-pressure sensor, 16-level gauge, 17-oil absorption filter, 18-air filter, 19-temperature sensor.
Detailed Description
A specific embodiment will be further described with reference to fig. 1.
1. Function of the main elements
The motor (2) drives the hydraulic pump (1) to provide a power source for the test system. The overflow valve group (4) is used for setting the highest pressure and unloading of the system. The proportional relief valve (6) is used for setting the actual required test pressure. The servo valve (9) can realize high-speed oil circuit switching and is used for controlling the movement direction and speed of the booster cylinder and providing pulse pressure signals and pressurizing signals for the booster cylinder. The pressure cylinder (10) has a pressure amplifying function and generates high-pressure test pressure pulses under the action of a servo valve pulse pressure signal. The pressure sensor b (13) is used for collecting pressure pulse signals and transmitting the pressure pulse signals to the industrial personal computer.
2. Test method
1) Pulse testing
The test hydraulic system is as shown in fig. 1, and an oil circuit at a pressure sensor b (13) is connected into a cavity of the tested multi-way valve.
The pressure signal is set through the pulse testing main interface of the industrial personal computer and is transmitted to the proportional overflow valve (6), and the test pressure required by the system is set.
Pulse signals are set through the pulse testing main interface of the industrial personal computer and transmitted to the servo valve (9), and the pulse frequency required by the test is set.
After the power-on, clicking a testing button on a pulse testing main interface of the industrial personal computer, starting the testing, and continuously applying high-voltage pulses to the cavity of the tested multi-way valve.
The industrial personal computer records and stores the pressure pulse signal number acquired by the pressure sensor b (13).
The number of pulses at which damage to the valve under test occurs is the fatigue life data for the valve.
2) Withstand voltage test
The test hydraulic system is as shown in fig. 1, and an oil circuit at a pressure sensor b (13) is connected into a cavity of the tested multi-way valve.
Pressure signals are set through a pressure-resistant testing main interface of the industrial personal computer and are transmitted to a proportional overflow valve (6), and test pressure required by the system is set.
A switch signal is arranged on a main interface of the withstand voltage test of the industrial personal computer, the signal is transmitted to a servo valve (9), and the pressurizing time required by the test is set.
After the power-on, clicking a testing button on a pressure-resistant testing main interface of the industrial personal computer, starting the testing, and applying high pressure to a cavity of the tested multi-way valve.
The industrial personal computer records and stores the time of the pressure signal acquired by the pressure sensor b (13).
The time at which the valve under test is damaged is the pressure life data of the valve.
The technical scheme adopted by the invention is as follows:
1 alternating stress loading fatigue test function setting
Pump working flow rate: maximum 80L/min;
The system outputs the highest pressure: 60Mpa;
the system outputs an alternating pressure frequency: 1-3 Hz;
The system outputs alternating pressure amplitude: the maximum pressure amplitude is 40Mpa, and is adjustable;
The waveform of the output alternating pressure is: triangular wave, sine wave and square wave, wherein the duty cycle of the square wave is adjustable.
2 High pressure test function setting
The system outputs working pressure: 50-90 MPa, adjustable;
High-pressure small flow rate output by the system: 0.1-1L/min is adjustable;
3 technical measures
The hydraulic source adopts a frequency converter to control the plunger pump, thus realizing stepless stable regulation and control of the flow rate of 0.1-80L/min.
And a proportional overflow valve is arranged to realize accurate control of pressure.
The two-stage supercharging is realized by adopting a supercharging cylinder so as to reach the ultrahigh pressure of 90 MPa.
The industrial personal computer is provided with a servo valve to respectively realize the frequency (1-3 Hz) control, the amplitude (40 Mpa) control and the waveform (triangular wave, sine wave and square wave) control of the pressure.
4 Technical characteristics
A novel hydraulic valve fatigue and high pressure resistant test bed,
1) The hydraulic source adopts a frequency converter to control the plunger pump, so that the large-span stepless stable regulation and control of the flow rate of 0.1-80L/min is realized.
2) The two-stage supercharging is realized by adopting a supercharging cylinder so as to reach the ultrahigh pressure of 90 MPa.
3) The upper computer is provided with a servo valve and a proportional pressure valve to respectively realize the control of the pressure frequency (1-3 Hz), the control of the amplitude (40 Mpa) and the control of the waveform (triangular wave, sine wave and square wave) of the hydraulic system required by the test.
4) Based on the three characteristics, the test bed can bear the fatigue test of the hydraulic valve and the high-pressure resistance test of the hydraulic valve.
Claims (1)
1. The test method of the hydraulic valve fatigue and high pressure resistance test bed comprises a hydraulic pump (1), a motor (2), a one-way valve a (3), an overflow valve group (4), a pressure gauge a (5), a proportional overflow valve (6), a high pressure filter (7), an energy accumulator (8), a servo valve (9), a booster cylinder (10), a one-way valve b (11), a pressure gauge b (12), a pressure sensor a (13), a safety valve (14), a pressure sensor b (15), a liquid level meter (16), an oil absorption filter (17), an air filter (18) and a temperature sensor (19);
the hydraulic pump (1) is connected with an oil tank through an oil suction filter (17), and a liquid level meter (16), an air filter (18) and a temperature sensor (19) are arranged in the oil tank;
The hydraulic pump (1) is driven by a motor (2), a hydraulic pipeline enters a parallel valve bank through an oil tank and a one-way valve a (3), the parallel valve bank comprises an overflow valve bank (4) and a proportional overflow valve (6), and the overflow valve bank (4) and the proportional overflow valve (6) are arranged in parallel between an oil inlet pipeline and an oil return pipeline; a pressure gauge a (5) and a pressure sensor b (15) are arranged on an oil inlet pipeline of the parallel valve bank;
An oil inlet pipeline through a parallel valve bank is connected with a booster cylinder (10) after passing through a high-pressure filter (7) and a servo valve (9); the servo valve (9) is connected with the accumulator (8), and a piston oil return port of the booster cylinder (10) is connected with the servo valve (9) through the one-way valve b (11) to form a hydraulic circuit; the pressurizing cylinder (10) is connected with the tested multi-way valve; a pressure gauge b (12) and a pressure sensor a (13) are arranged between the pressure cylinder (10) and the tested multi-way valve, and the pressure sensor a (13) is connected with a safety valve (14);
The motor (2) drives the hydraulic pump (1) to provide a power source for the test system; the overflow valve group (4) is used for setting the highest pressure and unloading of the system; the proportional overflow valve (6) is used for setting the actually required test pressure; the servo valve (9) can realize high-speed oil circuit switching and is used for controlling the movement direction and speed of the booster cylinder and providing pulse pressure signals and pressurizing signals for the booster cylinder; the pressure cylinder (10) has a pressure amplifying function and generates high-pressure test pressure pulses under the action of a servo valve pulse pressure signal; the pressure sensor b (15) is used for collecting a pressure pulse signal and transmitting the pressure pulse signal to the industrial personal computer; the time of the damage of the tested multi-way valve is the pressure-resistant life data of the valve;
the method is characterized in that: the test method of the test stand is as follows:
1) Pulse testing;
the oil way of the test hydraulic system at the pressure sensor b (15) is connected with the cavity of the tested multi-way valve;
setting a pressure signal through an industrial personal computer pulse test main interface, transmitting the pressure signal to a proportional overflow valve (6), and setting the test pressure required by the system;
Setting a pulse signal through a pulse testing main interface of an industrial personal computer, transmitting the pulse signal to a servo valve (9), and setting a pulse frequency required by a test;
After the power-on, clicking a testing button on a pulse testing main interface of the industrial personal computer, starting the testing, and continuously applying high-voltage pulses to a cavity of the tested multi-way valve;
The industrial personal computer records and stores the number of pressure pulse signals acquired by the pressure sensor b (15);
the pulse number when the tested multi-way valve is damaged is the fatigue life data of the valve;
2) Withstand voltage test;
the oil way of the test hydraulic system at the pressure sensor b (15) is connected with the cavity of the tested multi-way valve;
setting a pressure signal through a pressure-resistant testing main interface of the industrial personal computer, transmitting the pressure signal to a proportional overflow valve (6), and setting the test pressure required by the system;
Setting a switch signal through a main interface of the withstand voltage test of the industrial personal computer, transmitting the signal to a servo valve (9), and setting the pressurizing time required by the test;
after the power-on, clicking a testing button on a pressure-resistant testing main interface of the industrial personal computer, starting the testing, and applying high pressure to a cavity of the tested multi-way valve;
The industrial personal computer records and stores the time of the pressure signal acquired by the pressure sensor b (15).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711380909.4A CN107917123B (en) | 2017-12-20 | 2017-12-20 | Hydraulic valve fatigue and high pressure resistant test stand |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711380909.4A CN107917123B (en) | 2017-12-20 | 2017-12-20 | Hydraulic valve fatigue and high pressure resistant test stand |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107917123A CN107917123A (en) | 2018-04-17 |
| CN107917123B true CN107917123B (en) | 2024-05-24 |
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| CN201711380909.4A Active CN107917123B (en) | 2017-12-20 | 2017-12-20 | Hydraulic valve fatigue and high pressure resistant test stand |
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