CN111350721A - Testing arrangement of velocity of propagation of pressure wave in fluid - Google Patents

Testing arrangement of velocity of propagation of pressure wave in fluid Download PDF

Info

Publication number
CN111350721A
CN111350721A CN202010311762.9A CN202010311762A CN111350721A CN 111350721 A CN111350721 A CN 111350721A CN 202010311762 A CN202010311762 A CN 202010311762A CN 111350721 A CN111350721 A CN 111350721A
Authority
CN
China
Prior art keywords
oil
valve
hydraulic
tank
oil tank
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202010311762.9A
Other languages
Chinese (zh)
Inventor
李志丰
陈红军
胡思玉
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hunan Quality Supervision And Inspection Institute Commodities
Original Assignee
Hunan Quality Supervision And Inspection Institute Commodities
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hunan Quality Supervision And Inspection Institute Commodities filed Critical Hunan Quality Supervision And Inspection Institute Commodities
Priority to CN202010311762.9A priority Critical patent/CN111350721A/en
Publication of CN111350721A publication Critical patent/CN111350721A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • 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
    • F15B1/00—Installations or systems with accumulators; Supply reservoir or sump assemblies
    • F15B1/26—Supply reservoir or sump assemblies
    • 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
    • F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/08—Servomotor systems without provision for follow-up action; Circuits therefor with only one servomotor
    • 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
    • F15B13/04—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor
    • 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
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/04—Special measures taken in connection with the properties of the fluid
    • F15B21/041—Removal or measurement of solid or liquid contamination, e.g. filtering
    • 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
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/04—Special measures taken in connection with the properties of the fluid
    • F15B21/042—Controlling the temperature of the fluid
    • F15B21/0423—Cooling
    • 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
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/04—Special measures taken in connection with the properties of the fluid
    • F15B21/042—Controlling the temperature of the fluid
    • F15B21/0427—Heating
    • 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
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/04—Special measures taken in connection with the properties of the fluid
    • F15B21/044—Removal or measurement of undissolved gas, e.g. de-aeration, venting or bleeding
    • 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
    • F15B3/00—Intensifiers or fluid-pressure converters, e.g. pressure exchangers; Conveying pressure from one fluid system to another, without contact between the fluids
    • 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

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Fluid-Pressure Circuits (AREA)

Abstract

The invention provides a device for testing the propagation speed of pressure waves in oil. The device comprises a hydraulic pressurization oil way, a test oil way, a closed pressurization unit, a cooling unit and a heating unit; the hydraulic pressure boost oil circuit comprises a system oil tank, a main pump, a remote control unloading valve, a proportional servo valve, an electromagnetic directional valve, an energy accumulator, a first heat exchanger and a hydraulic pressure booster and is used for generating pulse waves. The test loop comprises a medium oil tank, an oil supplementing pump, a hydraulic steel pipe, a hydraulic control one-way valve and a second heat exchanger; the closed pressurizing unit comprises an auxiliary oil tank communicated with the medium oil tank, a vacuumizing degassing assembly arranged on the oil tank and a first stop valve; the heating unit is arranged in the medium oil tank. According to the invention, the heating unit and the cooling unit are designed, the temperature of the hydraulic oil is accurately controlled to +/-1 ℃, the interaction between the oil in the tested hydraulic steel pipe and the oil in the medium oil tank is carried out in the pulse process, and meanwhile, the temperature of the oil in the tested hydraulic steel pipe is controlled.

Description

Testing arrangement of velocity of propagation of pressure wave in fluid
Technical Field
The invention relates to the technical field of hydraulic detection devices, in particular to a device for testing the propagation speed of pressure waves in oil.
Background
The existing device for measuring the propagation speed of pressure waves in oil has the following problems:
(1) the resulting waveform and frequency cannot be adjusted and controlled and the results of the cumulative measurements cannot be averaged to improve detection accuracy.
(2) The generated pressure wave has echo after reflection, and the echo interferes with the measured pressure wave, so that the accuracy of a detection result is reduced.
(3) The pressure wave propagation speed of the oil liquid at different gas contents, temperatures and pressures cannot be tested.
In view of the above, there is a need for a device for measuring the propagation velocity of pressure waves in oil to solve the problems in the prior art.
Disclosure of Invention
The invention aims to provide a device for testing the propagation speed of a pressure wave in oil so as to solve the problem of measurement of the propagation speed of the pressure wave in the oil.
In order to achieve the aim, the invention provides a device for testing the propagation speed of pressure waves in oil, which comprises a hydraulic pressurizing oil way, a testing oil way, a closed pressurizing unit, a cooling unit and a heating unit, wherein the hydraulic pressurizing oil way is connected with the testing oil way;
the hydraulic pressure boost oil circuit comprises a system oil tank, a main pump, a remote control unloading valve, a proportional servo valve, an electromagnetic directional valve, an energy accumulator, a first heat exchanger and a hydraulic pressure booster; an oil outlet of the main pump is connected with an oil inlet of the proportional servo valve through a remote control unloading valve; two working oil ports of the proportional servo valve are respectively connected with a pressure oil port and an oil return port of the electromagnetic directional valve; two working oil ports of the electromagnetic directional valve are respectively connected with corresponding oil ports on the hydraulic pressure booster; the energy accumulator is arranged on the remote control unloading valve; the first heat exchanger is arranged on an oil return pipeline of the proportional servo valve; the first heat exchanger is connected with the cooling unit;
the test loop comprises a medium oil tank, an oil supplementing pump, a hydraulic steel pipe, a hydraulic control one-way valve and a second heat exchanger; two ends of the hydraulic steel pipe are respectively connected with an oil supplementing pump and a hydraulic pressure booster, and the hydraulic pressure booster returns oil to the medium oil tank through a hydraulic one-way valve; the second heat exchanger is arranged on an oil return pipeline of the hydraulic control one-way valve; the second heat exchanger is connected with the cooling unit;
the closed pressurizing unit comprises an auxiliary oil tank communicated with the medium oil tank, a vacuumizing degassing assembly arranged at the top of the oil tank and a first stop valve arranged at the bottom of the system oil tank;
the heating unit is arranged in the medium oil tank.
Preferably, pressure sensors are fixedly arranged at two ends of the hydraulic steel pipe, and the distance between the two pressure sensors is a fixed value and is smaller than the length of the hydraulic steel pipe.
Preferably, a first temperature sensor is arranged at the joint of the hydraulic steel pipe and the hydraulic pressure booster.
Preferably, two ends of the hydraulic steel pipe are respectively connected with the oil replenishing pump and the hydraulic pressure booster by adopting a hydraulic hose.
Preferably, a second temperature sensor and a liquid level sensor are arranged in the system oil tank and the medium oil tank.
Preferably, the medium oil tank pressing force container is designed to be of a fully-closed cylindrical structure.
Preferably, the middle upper part of the medium oil tank is provided with a viewing window for monitoring the liquid level and bubbles in the oil.
Preferably, a first safety valve is arranged on the medium oil tank to prevent the oil tank from being overpressurized.
Preferably, the vacuum pumping and degassing assembly comprises a vacuum pump, a filter and an electric ball valve which are connected in sequence; the vacuum pump is connected with the external atmosphere, and the electric ball valve is connected with the medium oil tank.
Preferably, the heating unit includes a heating oil pump, a first solenoid valve, and a second relief valve; an oil outlet of the heating oil pump is communicated with an oil inlet of the first electromagnetic valve; an oil outlet of the first electromagnetic valve returns oil to the medium oil tank; the second relief valve is disposed between the heating oil pump and the first solenoid valve.
Preferably, the cooling unit comprises a cooling water pump, a second stop valve, a second electromagnetic valve, a third electromagnetic valve and a one-way valve; the water outlet of the cooling water pump is communicated with the water inlet of the second stop valve; the water outlet of the second stop valve is respectively communicated with the water inlets of the second electromagnetic valve and the third electromagnetic valve, the water outlet of the second electromagnetic valve is communicated with the first heat exchanger or the second heat exchanger, and the water outlet of the third electromagnetic valve returns water to the cooling water tank; the one-way valve is arranged between the water outlets of the second electromagnetic valve and the third electromagnetic valve.
The technical scheme of the invention has the following beneficial effects:
(1) according to the invention, the heating unit and the cooling unit are designed, the temperature of the hydraulic oil is accurately controlled to +/-1 ℃, the interaction between the oil in the tested hydraulic steel pipe and the oil in the medium oil tank is carried out in the pulse process, and meanwhile, the temperature of the oil in the tested hydraulic steel pipe is controlled.
(2) The pressure wave generated in the oil circuit is a pulse wave, the frequency, the waveform and the experimental time of the pulse wave can be accurately controlled, the propagation speed of the pressure wave can be cumulatively and repeatedly measured, and then the average value is obtained, so that the accuracy of the measurement result is improved.
(3) The invention is provided with a plurality of pressure sensors and temperature sensors, the temperature and the pressure in the tested hydraulic steel pipe can be accurately measured, and the propagation speed of pressure waves in oil under different temperatures and pressures can be calculated.
(4) According to the invention, the two ends of the tested hydraulic steel pipe are connected into the device through the flexible high-pressure-resistant hydraulic hoses, and the hydraulic steel pipe is fixed on the device frame, so that the echo phenomenon generated after pressure wave reflection is reduced, and the accuracy of the test result is improved.
(5) In the invention, the medium oil tank adopts a sealing structure and is provided with the vacuumizing degassing assembly, thereby greatly reducing the influence of the external atmospheric environment on the test structure. The propagation speed of the pressure wave in the oil can be tested at different gas contents.
(6) The device reads the pressure value by externally connecting a high-frequency data acquisition system, the precision level reaches 0.1ms, and the requirement of the test is completely met. The device can also be used for durability pulse tests of partial hydraulic valves, hydraulic cylinders, hydraulic rubber pipes, hydraulic pumps and hydraulic motors.
In addition to the objects, features and advantages described above, other objects, features and advantages of the present invention are also provided. The present invention will be described in further detail below with reference to the drawings.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:
FIG. 1 is a schematic structural diagram of a testing device for the propagation speed of a pressure wave in oil;
FIG. 2 is a schematic structural view of a closed type pressurizing unit;
FIG. 3 is a time pressure graph;
the system comprises a system oil tank 1, a system oil tank 2, a main pump 3, a remote control unloading valve 4, a proportional servo valve 5, an electromagnetic directional valve 6, an energy accumulator 7, a first heat exchanger 8, a hydraulic pressure booster 9, a medium oil tank 10, an oil supplementing pump 11, a hydraulic steel pipe 12, a hydraulic control one-way valve 13, a second heat exchanger 14, an auxiliary oil tank 15, a first stop valve 16, a pressure sensor 17, a first temperature sensor 18, a second temperature sensor 19, a liquid level sensor 20, a safety valve 21, a vacuum pump 22, a filter 23, an electric ball valve 24, a heating oil pump 25, a first electromagnetic valve 26, a second safety valve 27, a cooling water pump 28, a second stop valve 29, a second electromagnetic valve 30, a third electromagnetic valve 31, a one-way valve 32, a cooling water tank 33 and a hydraulic hose.
Detailed Description
Embodiments of the invention will be described in detail below with reference to the drawings, but the invention can be implemented in many different ways, which are defined and covered by the claims.
Example 1:
referring to fig. 1 to 3, a device for testing the propagation speed of a pressure wave in oil comprises a hydraulic pressurizing oil path, a testing oil path, a closed pressurizing unit, a cooling unit and a heating unit;
the hydraulic pressure boost oil circuit comprises a system oil tank 1, a main pump 2, a remote control unloading valve 3, a proportional servo valve 4, an electromagnetic directional valve 5, an energy accumulator 6, a first heat exchanger 7 and a hydraulic pressure booster 8; an oil outlet of the main pump 2 is connected with an oil inlet of the proportional servo valve 4 through the remote control unloading valve 3; two working oil ports of the proportional servo valve 4 are respectively connected with a pressure oil port and an oil return port of the electromagnetic directional valve 5; two working oil ports of the electromagnetic directional valve 5 are respectively connected with corresponding oil ports on the hydraulic pressure booster 8; the energy accumulator 6 is arranged on the remote control unloading valve 3; the first heat exchanger 7 is arranged on an oil return pipeline of the proportional servo valve 4; the first heat exchanger 7 is connected with the cooling unit;
the test loop comprises a medium oil tank 9, an oil supplementing pump 10, a hydraulic steel pipe 11, a hydraulic control one-way valve 12 and a second heat exchanger 13; two ends of the hydraulic steel pipe 11 are respectively connected with an oil supplementing pump 10 and a hydraulic pressure booster 8 through a hydraulic hose 33, and the hydraulic pressure booster 8 returns oil to the medium oil tank 9 through a hydraulic one-way valve; the second heat exchanger 13 is arranged on an oil return pipeline of the hydraulic control one-way valve 12; the second heat exchanger 13 is connected to the cooling unit;
the closed pressurizing unit comprises an auxiliary oil tank 14 communicated with the medium oil tank 9, a vacuumizing degassing assembly arranged at the top of the oil tank and a first stop valve 15 arranged at the bottom of the system oil tank 1; the heating unit is arranged in the medium tank 9.
The two ends of the hydraulic steel pipe 11 are fixedly provided with pressure sensors 16, and the distance between the two pressure sensors 16 is a fixed value and is smaller than the length of the hydraulic steel pipe 11. A first temperature sensor 17 is arranged at the joint of the hydraulic steel pipe 11 and the hydraulic pressure booster 8.
A second temperature sensor 18 and a liquid level sensor 19 are arranged in the system oil tank 1 and the medium oil tank 9.
The cooling unit comprises a cooling water pump 27, a second stop valve 28, a second electromagnetic valve 29, a third electromagnetic valve 30 and a one-way valve 31; the water outlet of the cooling water pump 27 is communicated with the water inlet of the second stop valve 28; the water outlet of the second stop valve 28 is respectively communicated with the water inlets of a second electromagnetic valve 29 and a third electromagnetic valve 30, the water outlet of the second electromagnetic valve 29 is communicated with the first heat exchanger 7 or the second heat exchanger 13, and the water outlet of the third electromagnetic valve 30 returns water to the cooling water tank 32; a check valve 31 is provided between the outlets of the second and third solenoid valves 29, 30.
The heating unit includes a heating oil pump 24, a first electromagnetic valve 25, and a second relief valve 26; an oil outlet of the heating oil pump 24 is communicated with an oil inlet of the first electromagnetic valve 25; the oil outlet of the first electromagnetic valve 25 returns oil to the medium oil tank 9; a second relief valve 26 is provided between the heating oil pump 24 and the first solenoid valve 25.
The embodiment is used for measuring the propagation speed of the pulse pressure wave in oil. The principle is shown in fig. 1.
The length of the tested hydraulic steel pipe is 5.2m, the wall thickness is 3mm, the inner diameter is 12mm, and the distance between the pressure sensors fixed at the two ends is 5 m. The temperature of the medium oil tank can be adjusted and controlled through the heating unit and the cooling unit, and the precision can be controlled to +/-1 ℃. Through oil supplementing pump, check valve and hydraulic control check valve, the interaction of the oil in the tested hydraulic steel pipe and the oil in the medium oil tank in the pulse process is realized, thereby realizing the control of the temperature of the oil in the tested hydraulic steel pipe. The pressure value and the temperature value can be read by externally connecting a high-frequency data acquisition system.
The pressure wave is a pulse wave, and the specific principle of generating the pressure wave is as follows: first, the main oil pump is started and pressurized to a working pressure specified in the test. At this stage, the energy accumulator is charged, the proportional servo valve works at the left position, the electromagnetic directional valve is in a closed state, the flow output by the pump does not flow into the hydraulic pressure booster and the test piece, the pressure of a pipeline from the energy accumulator to the electromagnetic directional valve is equal to the pressure of accumulated output, and the flow is zero; and the pressure and the flow of the section of the pipeline from the electromagnetic directional valve to the tail end of the test piece are zero. And then, a computer sends out a control signal, the frequency of the control signal is set according to the test specification, the electromagnetic directional valve is controlled to act, and the control valve works at the left position, so that the pressure in the energy accumulator is oil, the oil rapidly flows into a low-pressure cavity of the supercharger through the proportional servo valve, and the piston of the hydraulic supercharger is pushed to rapidly move. Thereby generating a pressure wave in the hydraulic steel pipe to be tested. The trace of the hydraulic pulse wave can be tested at the pressure test point. At the moment, because the electromagnetic reversing valve is not closed, meanwhile, because a hydraulic pressure booster piston has a certain damping coefficient and static friction, hydraulic oil has viscosity, so that a pulse waveform is attenuated and then can be maintained under a certain pressure, the pressure is called as steady-state working pressure, when the falling edge of a control signal is reached, the electromagnetic reversing valve works at the right position, a low-pressure cavity of the hydraulic pressure booster is communicated with an oil return circuit, so that the piston is retracted to the original position, and the pressure of a test piece is rapidly reduced to be close to zero, so that the operation is repeated. The waveform of the pulse adopts a square wave, as shown in fig. 3:
as shown in fig. 2, the medium tank 9 is a closed tank, which is used as a normal tank when the hydraulic system is in operation, and is connected to an oil pump and a system return oil, and is used as a vacuum container when vacuum-pumping is performed, and is connected to a vacuum degassing device. The pressing force container design of the medium oil tank 9 adopts a fully-closed cylindrical structure.
The bottom of the medium oil tank 9 is provided with a stop valve for filling oil and discharging oil of the hydraulic system and providing oil samples for a gas content detecting instrument, and the top is provided with a stop valve for discharging gas of the system. And the middle upper part of the medium oil tank 9 is provided with an observation window for monitoring liquid level and bubbles in oil.
At the same time, a first safety valve 20 is provided to prevent an overpressure in the medium tank. The hydraulic system is additionally provided with an auxiliary oil tank which is communicated with the closed oil tank, is used for adjusting the oil quantity balance of the system in the working process of the hydraulic system and is used for storing redundant oil in the closed oil tank in the vacuum-pumping treatment. The auxiliary oil tank is loaded by an electric loading device and mainly comprises a motor, a gear set and a lead screw, certain pressure can be applied to internal oil when the piston is in a free state, and the oil is isolated from the atmosphere by sealing the outer ring of the piston.
The vacuumizing and degassing assembly comprises a vacuum pump 21, a filter 22 and an electric ball valve 23 which are connected in sequence; the vacuum pump 21 is connected to the outside atmosphere, and the electric ball valve 23 is connected to the medium tank 9.
The closed medium reservoir acts as a vacuum vessel. After the preparation such as temperature adjustment, system switching and the like is finished, the vacuum-pumping treatment can be carried out, and the method comprises the following steps:
(1) generating a negative pressure environment
And closing a stop valve between the closed oil tank and the auxiliary oil tank, and pumping oil in the closed oil tank into the auxiliary oil tank by using an electric pump. Then the piston of the auxiliary oil tank is limited at the current position, and a stop valve between the oil tanks is opened, and the pressure of the two oil tanks is in a negative pressure environment. Because the oil pressure is reduced, the air is dissolved and supersaturated, and redundant gas in the oil is gradually released.
(2) Vacuumizing and degassing
And starting the vacuum pump, operating the electric ball valve to open, communicating the oil tank with the vacuum pump, and discharging gas in the oil tank to further reduce the pressure of the oil tank. When the pressure in the oil tank is lower than the oil-gas separation pressure, the dissolved gas is gradually separated out, and the gas is immediately sucked away by the vacuum pump after being released. Different vacuumizing time can be controlled during the period, so that the gas content in the oil is different.
(3) Standing the oil liquid in a vacuum environment
Because the speed that oil-gas separation and bubble totally appear the liquid level is less than the speed of bleeding of vacuum pump, if the oil tank internal pressure is less than the saturated vapor pressure of fluid moreover will lead to fluid atomizing, consequently when detecting the pressure value of vacuum sensor and crossing low, operate the electronic ball valve immediately and close, cut off the return circuit of bleeding, close the vacuum pump simultaneously. At the moment, the oil is allowed to stand in a vacuum environment for a period of time, gas is continuously released from the oil, and the pressure of the oil tank is gradually increased.
(4) Restoring the liquid level and pressure of the oil tank
And after the vacuum pumping treatment is finished, keeping the closing state of the electric ball valve. And the position limitation of a piston in the auxiliary oil tank is cancelled, the piston slowly returns to the initial position under the action of atmospheric pressure, and the liquid level and the pressure in the closed oil tank are recovered. During the period, the gas content is detected through an external gas content detector, so that the pressure wave propagation speed detection under different gas contents is realized.
The specific test process of the propagation speed of the pressure wave in the oil is as follows: the maximum pressure value and the frequency of the pulse in the tested hydraulic steel pipe can be adjusted. The pressure values of the two points during the generation of the pulse wave are measured by setting the pressure pulse wave generated in a period of time, and a time-pressure curve graph is drawn (a part of the curve is omitted).
As shown in FIG. 3, when A, B, C, D, E, F, G, H are the same pressure values, the time values of the time points corresponding to the two curves are TA, TB, TC, TD, TE, TF, TG, TH, T, respectively1＝TB-TA，T2＝TD-TC，T3＝TF-TE，T4TH-TG. Finally, taking the average value T ═ T (T)1+T2+T3+T4) And 4 (more values can be taken according to needs to be calculated again, and the result is more accurate by repeatedly measuring and averaging), and the propagation distance is 5m (the length of the tested hydraulic steel pipe), so that the propagation speed c of the pressure wave can be obtained.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. A testing device for the propagation speed of pressure waves in oil is characterized by comprising a hydraulic pressurizing oil way, a testing oil way, a closed pressurizing unit, a cooling unit and a heating unit;
the hydraulic pressure boost oil circuit comprises a system oil tank (1), a main pump (2), a remote control unloading valve (3), a proportional servo valve (4), an electromagnetic directional valve (5), an energy accumulator (6), a first heat exchanger (7) and a hydraulic pressure booster (8); an oil outlet of the main pump (2) is connected with an oil inlet of the proportional servo valve (4) through the remote control unloading valve (3); two working oil ports of the proportional servo valve (4) are respectively connected with a pressure oil port and an oil return port of the electromagnetic directional valve (5); two working oil ports of the electromagnetic directional valve (5) are respectively connected with corresponding oil ports on the hydraulic pressure booster (8); the energy accumulator (6) is arranged on the remote control unloading valve (3); the first heat exchanger (7) is arranged on an oil return pipeline of the proportional servo valve (4); the first heat exchanger (7) is connected with the cooling unit;
the test loop comprises a medium oil tank (9), an oil supplementing pump (10), a hydraulic steel pipe (11), a hydraulic control one-way valve (12) and a second heat exchanger (13); two ends of the hydraulic steel pipe (11) are respectively connected with an oil supplementing pump (10) and a hydraulic pressure booster (8), and the hydraulic pressure booster (8) returns oil to the medium oil tank (9) through a hydraulic one-way valve; the second heat exchanger (13) is arranged on an oil return pipeline of the hydraulic control one-way valve (12); the second heat exchanger (13) is connected with the cooling unit;
the closed pressurizing unit comprises an auxiliary oil tank (14) communicated with the medium oil tank (9), a vacuumizing degassing assembly arranged at the top of the oil tank and a first stop valve (15) arranged at the bottom of the system oil tank (1);
the heating unit is arranged in the medium oil tank (9).
2. The device for testing the propagation speed of the pressure wave in the oil according to claim 1, wherein the two ends of the hydraulic steel pipe (11) are fixedly provided with the pressure sensors (16), and the distance between the two pressure sensors (16) is a fixed value and is smaller than the length of the hydraulic steel pipe (11).
3. The device for testing the propagation speed of the pressure wave in the oil according to the claim 2, characterized in that the first temperature sensor (17) is arranged at the joint of the hydraulic steel pipe (11) and the hydraulic pressure booster (8).
4. The device for testing the propagation speed of the pressure wave in the oil according to claim 3, wherein two ends of the hydraulic steel pipe (11) are respectively connected with the oil supplementing pump (10) and the hydraulic pressure booster (8) by using hydraulic hoses (33).
5. A device for measuring the propagation velocity of a pressure wave in oil according to claim 1, characterized in that a second temperature sensor (18) and a level sensor (19) are provided in both the system tank (1) and the medium tank (9).
6. The device for testing the propagation speed of the pressure wave in the oil according to the claim 5, characterized in that the pressing force container design of the medium oil tank (9) adopts a fully-closed cylindrical structure; and the middle upper part of the medium oil tank (9) is provided with an observation window for monitoring the liquid level and bubbles in the oil liquid.
7. A device for testing the propagation speed of a pressure wave in an oil according to claim 6, characterized in that a first relief valve (20) is provided in the tank (9) to prevent overpressure in the tank.
8. The device for testing the propagation speed of the pressure wave in the oil according to the claim 1, characterized in that the vacuum degassing assembly comprises a vacuum pump (21), a filter (22) and an electric ball valve (23) which are connected in sequence; the vacuum pump (21) is connected with the external atmosphere, and the electric ball valve (23) is connected with the medium oil tank (9).
9. The device for testing the propagation speed of a pressure wave in oil according to any one of claims 1 to 8, wherein the heating unit comprises a heating oil pump (24), a first electromagnetic valve (25) and a second safety valve (26); an oil outlet of the heating oil pump (24) is communicated with an oil inlet of the first electromagnetic valve (25); an oil outlet of the first electromagnetic valve (25) returns oil to the medium oil tank (9); a second relief valve (26) is provided between the heating oil pump (24) and the first electromagnetic valve (25).
10. The device for testing the propagation speed of a pressure wave in oil according to claim 9, wherein the cooling unit comprises a cooling water pump (27), a second stop valve (28), a second electromagnetic valve (29), a third electromagnetic valve (30) and a check valve (31); the water outlet of the cooling water pump (27) is communicated with the water inlet of the second stop valve (28); the water outlet of the second stop valve (28) is respectively communicated with the water inlets of a second electromagnetic valve (29) and a third electromagnetic valve (30), the water outlet of the second electromagnetic valve (29) is communicated with the first heat exchanger (7) or the second heat exchanger (13), and the water outlet of the third electromagnetic valve (30) returns water to the cooling water tank (32); the one-way valve (31) is arranged between the water outlets of the second electromagnetic valve (29) and the third electromagnetic valve (30).
CN202010311762.9A 2020-04-20 2020-04-20 Testing arrangement of velocity of propagation of pressure wave in fluid Pending CN111350721A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010311762.9A CN111350721A (en) 2020-04-20 2020-04-20 Testing arrangement of velocity of propagation of pressure wave in fluid

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010311762.9A CN111350721A (en) 2020-04-20 2020-04-20 Testing arrangement of velocity of propagation of pressure wave in fluid

Publications (1)

Publication Number Publication Date
CN111350721A true CN111350721A (en) 2020-06-30

Family

ID=71193263

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010311762.9A Pending CN111350721A (en) 2020-04-20 2020-04-20 Testing arrangement of velocity of propagation of pressure wave in fluid

Country Status (1)

Country Link
CN (1) CN111350721A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112483511A (en) * 2020-12-08 2021-03-12 四川凌峰航空液压机械有限公司 Variable pressure ratio hydraulic pressure boost test system
CN112664516A (en) * 2020-11-25 2021-04-16 河南航天液压气动技术有限公司 Fuzzy control theory-based high-lift-rate water hammer generator and working method thereof

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112664516A (en) * 2020-11-25 2021-04-16 河南航天液压气动技术有限公司 Fuzzy control theory-based high-lift-rate water hammer generator and working method thereof
CN112483511A (en) * 2020-12-08 2021-03-12 四川凌峰航空液压机械有限公司 Variable pressure ratio hydraulic pressure boost test system

Similar Documents

Publication Publication Date Title
CN107014721B (en) Device and method for evaluating sand carrying performance of carbon dioxide dry fracturing fluid
CN111350721A (en) Testing arrangement of velocity of propagation of pressure wave in fluid
CN208443568U (en) A kind of multifunctional pulse multi-function test stand
NO854539L (en) PROCEDURE FOR DETERMINING PUMP CHARACTERISTICS, AND PUMP FOR EXECUTING THE PROCEDURE.
CN1906378A (en) Measuring fluid volumes in a container using pressure
CN104395712A (en) Measuring the volume of fluid in a vessel
CN101435712B (en) Device for measuring air volume flow
CN212202711U (en) Testing arrangement of velocity of propagation of pressure wave in fluid
CN109708896B (en) Quantitative filling device and method for attitude control power system
CN108730266A (en) Discharge measuring device and method in a kind of hydraulic cylinder
CN113465931A (en) Variable cross-section shock wave induced ultra-low pressure self-ignition experimental device and method
NO305850B1 (en) Flow measurement method and apparatus
EP2363669A2 (en) Maintenance device for conditioning systems
CN108627437B (en) Gas micro-flow measuring device and method under reservoir conditions for experiment
CN102951589B (en) Apparatus for filling conducting medium into single-hole closed small container
CN105842138B (en) A kind of mercury column interface automatic regulating system and rock core pore structure analyzer
CN210465170U (en) Tensile test device for strain rate in hydraulic and pneumatic motion
CN210401098U (en) Hydraulic and pneumatic stress in motion strain rate stretching and compressing universal test device
CN103231815B (en) System and method for automatically filling working medium for water sublimator
US11802827B2 (en) Single stage MICP measurement method and apparatus
RU2204118C2 (en) Process testing tightness of articles
CN2453426Y (en) Water pressure testing devicefor pressure container
CN214374490U (en) High-precision hydraulic oil effective volume elastic modulus detection device
JPH07318401A (en) Method and device for testing expansion
CN112525500B (en) Comprehensive calibration system for hydraulic harpoon device

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination