A calibration system and working method for a high-pressure oil flowmeter

Abstract

The present invention discloses a verification and calibration system for a high-pressure oil flowmeter and its working method, including an adjustable stepless variable high-pressure liquid supply device, a working liquid parameter guarantee system, a working liquid transportation control and the tested flowmeter clamping system, a working liquid weighing and metering system, and a process control system. The present invention has great direct economic benefits in the field of oil product transportation metering and settlement. The present invention can accurately verify and calibrate the high-pressure oil flowmeter, so that in a hydraulic test system using the in-use high-pressure oil flowmeter as a standard source, it can accurately reflect the quality level of the tested hydraulic components or systems, and at the same time provide accurate data support for the production and manufacturing of hydraulic components and systems. The present invention can provide accurate data support for production enterprises and provide data basis in links such as product R & D, production and manufacturing, factory inspection, debugging and calibration.

Description

Technical Field

[0001] The present invention relates to the field of verification and calibration of high-pressure oil flowmeters, and particularly to a verification and calibration system for high-pressure oil flowmeters and a method for using the same. Background Art

[0002] Existing verification and calibration devices for flowmeters cannot fully simulate the verification or calibration of high-pressure oil flowmeters under actual use conditions in a verification and calibration laboratory, and can only perform verification and calibration under normal pressure. Common methods include the standard flowmeter method and the weighing method. The standard flowmeter method is to use a flowmeter with higher accuracy as a standard source to verify a flowmeter with lower accuracy, also known as the comparison method. There are two ways of the weighing method. For a flowmeter with a flow rate display value, it is to use a weighing device to weigh the weight of the liquid passing through the flowmeter to be tested within a certain period of time, and calculate its standard flow rate through calculation, and compare it with the displayed flow rate value of the flowmeter to be tested for verification or calibration; the second is for the flowmeter to be tested with pulse metering or cumulative counting. After passing a certain amount of liquid through the flowmeter to be tested, and then weighing it and calculating the volume to compare with the metering value of the flowmeter to be tested, the accuracy or coefficient of the flowmeter to be tested is obtained.

[0003] When a high-pressure oil flowmeter is in use, it works in a high-pressure environment and is accompanied by high temperature. Using the existing devices and test methods for verification and calibration, the following problems mainly exist:

[0004] First, it is impossible to evaluate the influence of the coefficient change caused by the deformation of components of the high-pressure flowmeter under the pressure-bearing environment on the measurement accuracy; second, it is impossible to evaluate the influence of liquid turbulence on the measurement accuracy when the fluid passes through the flowmeter under high-pressure conditions. Third, it is impossible to evaluate the influence of the solubility of the gas contained in the working liquid at different pressures on the actual measurement accuracy; fourth, existing flow calibration devices generally use water-based or diesel as the working liquid, while the general working liquid of high-pressure oil flowmeters is hydraulic oil. Using water-based or diesel to verify and calibrate high-pressure oil flowmeters, due to the different viscosities and lubricities of the working liquids, the resistance and driving force when the metering components inside the high-pressure oil flowmeter rotate are different, and it is impossible to accurately verify and calibrate the accurate parameters and accuracy of the oil flowmeter during actual operation. Fifth, existing flow calibration devices generally operate in a constant temperature room of a flow laboratory, and the temperature is generally a constant 20 degrees Celsius. However, for the working environment of high-pressure oil flowmeters, the standard oil liquid temperature is between 30 and 80 degrees. The existing system has no working liquid temperature adaptation device, and it is impossible to evaluate the interference of temperature on parameters such as pipelines, components, and oil product density on the measurement accuracy and standard coefficient. Summary of the Invention

[0005] The purpose of the present invention is to provide a verification and calibration system for high-pressure oil flowmeters in view of the deficiencies of the prior art.

[0006] In order to achieve the above purposes, the present invention adopts the following technical solutions:

[0007] A calibration system for a high-pressure oil flowmeter, comprising an adjustable stepless variable high-pressure liquid supply device, a working liquid parameter guarantee system, a working liquid transportation control and test flowmeter clamping system, a working liquid weighing and metering system, and a process control system.

[0008] The adjustable stepless variable high-pressure liquid supply device includes a frequency conversion motor, a servo variable plunger pump, a servo flow regulator, and a coupling. The frequency conversion motor is connected to the servo variable plunger pump through the coupling. The servo flow regulator is arranged on the servo variable plunger pump. The servo variable plunger pump is connected to the working liquid parameter guarantee system through a liquid suction pipe and extracts the working liquid in the working liquid parameter guarantee system.

[0009] The working liquid transportation control and test flowmeter clamping system includes a high-pressure gas precipitation device, a high-pressure gas precipitation device, a test flowmeter, a standard high-pressure flowmeter, and a servo pressure regulator. The high-pressure gas precipitation device is connected to the front end of the test flowmeter through a front-end high-pressure telescopic straight pipe section. The rear end of the test flowmeter is connected to the standard high-pressure flowmeter through a rear-end high-pressure straight pipe section. The other end of the standard high-pressure flowmeter is connected to the servo pressure regulator. The servo pressure regulator is connected with a commutator return liquid pipe and a commutator outlet liquid pipe through a three-way servo commutator. The commutator return liquid pipe is connected to the rear part of the working liquid parameter guarantee system. The commutator outlet liquid pipe is connected to the upper part of the working liquid weighing and metering system. The lower part of the working liquid weighing and metering system is connected to the working liquid parameter guarantee system.

[0010] The servo variable plunger pump and the three-way servo commutator are connected to the process control system for control.

[0011] Furthermore, the working liquid parameter guarantee system includes an oil tank, a heating device, a magnetic filter, and an oil tank temperature sensor. The oil tank is filled with the working liquid. An oil suction filter is installed on the inner wall of the oil tank corresponding to the liquid suction pipe for extracting the working liquid through the oil suction filter. The heating device and the oil tank temperature sensor are fixed on the oil tank cover. The lower part of the heating device is immersed in the working liquid. The magnetic filter is arranged in the oil tank behind the heating device. The servo variable plunger pump is connected to the oil tank through the liquid suction pipe.

[0012] Furthermore, the oil tank is also provided with an anti-foaming net and a water-cooled cooler. The anti-foaming net is arranged on both sides of the magnetic filter. The water-cooled cooler is arranged at the lower part of the oil tank.

[0013] Furthermore, the front end of the test flowmeter is connected to the front-end high-pressure telescopic straight pipe section through a front connection device and a front connection device fixing bolt. The rear end of the test flowmeter is connected to the standard high-pressure flowmeter through a rear connection device fixing bolt and a rear connection device. The test flowmeter and the standard high-pressure flowmeter are connected to the process control system.

[0014] Further, a front pressure and temperature sensor is installed at the front end above the front high-pressure telescopic straight pipe section, and a rear pressure and temperature sensor is installed at the rear end above the rear high-pressure straight pipe section. The front pressure and temperature sensor and the rear pressure and temperature sensor are connected to the process control system for control.

[0015] Further, the working liquid weighing and metering system includes a weighing oil tank, an on-line densitometer, an electric drain valve, and a weighing tank temperature sensor. The weighing oil tank is filled with a metering liquid, which is the liquid flowing through the flowmeter under test during the verification process. The outer side of the weighing oil tank is connected to the weighing sensor below through a weighing bracket. A weighing tank temperature sensor is installed on the upper wall of the weighing oil tank, and the lower part of the weighing tank temperature sensor is immersed in the metering liquid. An on-line densitometer is also provided above the metering liquid. The electric drain valve, the weighing sensor, the on-line densitometer, the oil tank temperature sensor, and the weighing tank temperature sensor are connected to the process control system.

[0016] Further, the lower center of the weighing oil tank is inserted and connected to the working liquid parameter guarantee system through an electric drain valve and a manifold pipe, without mechanical part contact.

[0017] Further, the process control system includes a full-parameter display and control instrument, a system preparation button, a preparation completion indicator light, a test start button, and a test completion indicator light installed on a controller bracket. The full-parameter display and control instrument is used to control each device connected to it in the system.

[0018] Further, the servo variable plunger pump is fixed on the base through a pump bracket.

[0019] The present invention also includes a working method of a verification and calibration system for a high-pressure oil flowmeter, which includes the following steps:

[0020] Step 1: Installation implementation of the flowmeter under test: Select a front connection device, a rear connection device, front connection device bolts, and rear connection device bolts that match the inlet and outlet oil ports of the flowmeter under test, and fix the flowmeter under test in the verification and calibration loop.

[0021] Step 2: System preparation implementation: Keep the temperature of the oil-based working liquid constant at the standard working temperature, adjust the output flow of the servo variable plunger pump to the verification and calibration flow, position the three-way servo commutator in the return liquid state, and place the electric drain valve in the closed state after emptying the weighing oil tank.

[0022] Step 3. System calibration process: After the system is prepared, the system does not stop. When the test start button is pressed, the full-parameter display controller starts to output a loading signal to the servo pressure regulator until the return value of the front-end pressure and temperature sensor matches and remains the same as the set value of the full-parameter display controller. At this time, the return value of the secondary detection is compared with the flow value set in the full-parameter display controller to complete the parameter calibration.

[0023] Step 4. Oil discharge implementation of the weighing system: The metered liquid after weighing is returned to the fuel tank after weighing. After starting the liquid discharge process, first, the full-parameter display controller detects the return value of the weighing sensor. If it is greater than the no-load value, the electric liquid discharge valve is placed in the open position, and the metered liquid flows into the manifold through the current liquid discharge valve and returns to the fuel tank. After the return value of the weighing sensor reaches the set no-load value, the electric liquid discharge valve is placed in the switch position to complete one oil discharge process.

[0024] Adopting the technical solution of the present invention, the beneficial effects of the present invention are as follows:

[0025] First, in the field of oil product transportation metering and settlement, the accuracy of the high-pressure oil flowmeter directly affects the settlement result, which is of great significance to both parties and has relatively large direct economic benefits.

[0026] Second, when used in the testing field of hydraulic components and systems, the high-pressure oil flowmeter is used as a standard source of flow. It will directly evaluate the volumetric efficiency of the tested hydraulic components under different pressure states. Accurately calibrating the high-pressure oil flowmeter can accurately reflect the quality level of the tested hydraulic components or systems in the hydraulic test system using the in-use high-pressure oil flowmeter as a standard source. At the same time, it also provides accurate data support for the production and manufacturing of hydraulic components and systems, which is of great significance for improving the manufacturing and debugging levels of hydraulic components and systems.

[0027] Third, accurately calibrating the high-pressure oil flowmeter is also of great significance to the production enterprises of high-pressure oil flowmeters. It can provide accurate data support and provide data basis for product R & D, production and manufacturing, factory inspection, calibration and debugging, etc. Description of the Drawings

[0028] Figure 1 It is a schematic diagram of a calibration system for a high-pressure oil flowmeter provided by the present invention.

[0029] Among them, 1. variable frequency speed regulation motor, 2. servo variable displacement piston pump, 3. servo flow regulator, 4. pump support, 5. base, 6. coupling, 7. oil tank, 8. suction filter, 9. working liquid, 10. heating device, 11. magnetic filter, 12. water-cooled cooler, 13. return liquid pipe, 14. front-end high-pressure telescopic straight pipe section, 15. rear-end high-pressure telescopic straight pipe section, 16. front-end pressure and temperature sensor, 17. rear-end pressure and temperature sensor, 18. high-pressure gas precipitation device, 19. standard high-pressure flow meter, 20. servo pressure regulator, 21. three-way servo commutator, 22. commutator return liquid pipe, 23. commutator liquid outlet pipe, 24. flow meter under test, 25. front connection device bolt, 26. rear connection device bolt, 27. front connection device, 28. rear connection device, 29. suction liquid pipe, 30. defoaming net, 31. weighing oil tank, 32. on-line densitometer, 33. electric drain valve, 34. manifold pipe, 35. load cell, 36. weighing support, 37. metering liquid, 38. oil tank cover plate, 39. oil tank temperature sensor, 40. weighing tank temperature sensor, 41. controller support, 42. full-parameter display and control instrument, 43. system preparation button, 44. preparation completed indicator light, 45. test start button, 46. test completed indicator light. Specific implementation manner

[0030] The specific embodiments of the specific solutions of the present invention will be further described in conjunction with the accompanying drawings.

[0031] As shown in the figure, a verification and calibration system for a high-pressure oil flow meter includes an adjustable stepless variable high-pressure liquid supply device, a working liquid parameter guarantee system, a working liquid transportation control and flow meter under test clamping system, a working liquid weighing and metering system, and a process control system.

[0032] I. Adjustable stepless variable high-pressure liquid supply device: It includes a variable frequency motor 1, a servo variable displacement piston pump 2, a servo flow regulator 3, a pump support 4, a base 5, and a coupling 6 as shown in the figure. The variable frequency motor 1 is connected to the servo variable displacement piston pump 2 through the coupling 6. The servo flow regulator 3 is arranged on the servo variable displacement piston pump 2. The servo variable displacement piston pump 2 is connected to the oil tank 7 of the working liquid parameter guarantee system through the suction liquid pipe 29. Its function is to provide a stable oil source with adjustable pressure and flow for the high-pressure oil flow meter to be verified and calibrated.

[0033] Main functions and implementation of each component of this system: The variable-frequency motor 1 serves as the power source of this system and drives the servo variable plunger pump 2 to work through the coupling 6. The servo variable plunger pump 2 is fixed on the base 5 through the pump bracket 4. The servo variable plunger pump 2 serves as the high-pressure working liquid output device of this system. Driven by the variable-frequency motor 1, it extracts the working liquid 9 from the oil tank 7 through the suction pipe 29 via the oil suction filter 8, and under the control of the full-parameter controller 42, by controlling the servo flow regulator 3, it outputs the working liquid flow rate set by the full-parameter controller 42.

[0034] II. Working liquid parameter guarantee system: mainly includes the oil tank 7 and the oil suction filter 8, working liquid 9, heating device 10, magnetic filter 11, water-cooled cooler 12, defoaming net 30, and oil tank temperature sensor 39 installed inside. The oil tank 7 contains the working liquid 9. The oil suction filter 8 is installed on the inner wall of the oil tank 7 corresponding to the suction pipe 29 and is used to extract the working liquid 9 through the oil suction filter 8. The heating device 10 and the oil tank temperature sensor 39 are fixed on the oil tank cover 38. The lower part of the heating device 10 is immersed in the working liquid 9. The magnetic filter 11 is arranged in the oil tank 7 behind the heating device 10. The servo variable plunger pump 2 is connected to the oil tank 7 through the suction pipe 29. The oil tank 7 is also provided with a defoaming net 30 and a water-cooled cooler 12. The defoaming net 30 is arranged on both sides of the magnetic filter 11, and the water-cooled cooler 12 is arranged at the lower part of the oil tank 7.

[0035] The main function of this system is to provide the working liquid meeting the actual working environment temperature for the high-pressure oil flowmeter to be calibrated, provide heating and heat dissipation functions for the working liquid, and keep the oil temperature constant during the test process to eliminate the influence of temperature change on the calibration accuracy during the calibration process. The functions of the oil suction filter 8, magnetic filter 11, and defoaming net 30 in the oil tank are to ensure that the working liquid meets the requirements of the high-pressure oil flowmeter to be calibrated for the filtration accuracy of the working liquid and complete the filtration and defoaming treatment of the working liquid.

[0036] Functions and implementation of each component of this system: Oil tank 7: serves as the container of the working liquid and the installation base of each oil temperature control device, contains the working liquid 9 inside, and is internally installed with an oil suction filter 8 for filtering impurities, a magnetic filter 11 for absorbing iron-based impurities, a heating device 10 for heating the working liquid, a water-cooled cooler 12 for cooling the working liquid, a defoaming net 30 for eliminating bubbles in the reflux working liquid, and an oil tank cover 38 as the installation base for the devices on its upper part.

[0037] III. Working Liquid Delivery Control Test Flowmeter Clamping System This system mainly includes a high-pressure gas precipitation device 18 as shown in the figure, a front-end high-pressure telescopic straight pipe section 14, a front-end pressure and temperature sensor 16 installed on it, a front connection device 27, front connection device fixing bolts 25, a test flowmeter 24, rear connection device fixing bolts 26, a rear connection device 28, a rear-end high-pressure straight pipe section 15, a rear-end pressure and temperature sensor 17 installed on it, a standard high-pressure flowmeter 19, a servo pressure regulator 20, a three-way servo commutator 21, a commutator return liquid pipe 22, and a commutator liquid outlet pipe 23.

[0038] The high-pressure gas precipitation device 18 is connected to the front end of the test flowmeter 24 through the front-end high-pressure telescopic straight pipe section 14. The rear end of the test flowmeter 24 is connected to the standard high-pressure flowmeter 19 through the rear-end high-pressure straight pipe section 15. The other end of the standard high-pressure flowmeter 19 is connected to the servo pressure regulator 20. The servo pressure regulator 20 is connected with a commutator return liquid pipe 22 and a commutator liquid outlet pipe 23 through a three-way servo commutator 21. The commutator return liquid pipe 22 is connected to the rear part of the working liquid parameter guarantee system fuel tank 7. The commutator liquid outlet pipe 23 is connected to the upper part of the working liquid weighing and metering system. A front-end pressure and temperature sensor 16 is installed at the front end above the front-end high-pressure telescopic straight pipe section 14, and a rear-end pressure and temperature sensor 17 is installed at the rear end above the rear-end high-pressure straight pipe section 15.

[0039] The main functions of each component of this system:

[0040] High-pressure gas precipitation device 18: Discharge the undissolved air inside the working liquid output by the adjustable stepless variable high-pressure oil supply device;

[0041] Front-end high-pressure telescopic straight pipe section 14: Connected to the high-pressure gas precipitation device 18, its function is to introduce the working liquid after the air is precipitated by the high-pressure gas precipitation device 18 into the test flowmeter 24 through the front connection device 27. A front-end pressure and temperature sensor 16 is installed on it to measure the real-time pressure and temperature of the working liquid passing through the test flowmeter 24 during the calibration process for parameter correction during later metering;

[0042] Front connection device 27 and front connection device fixing bolts 25: Have various structural dimensions to adapt to test flowmeters 24 with different connection dimensions and pipe diameters, but the outer diameter dimension is fixed. It can be inserted into the front-end high-pressure telescopic straight pipe section 14 and can have a certain amount of expansion and contraction to adapt to the connection of test flowmeters 24 with different lengths, and is connected to the test flowmeter 24 through the front connection device fixing bolts 25;

[0043] Rear connection device 28 and rear connection device fixing bolt 26: There are various structural dimensions to adapt to different connection dimensions and diameters of the flowmeter under test 24, but the outer diameter dimension is fixed and is fixedly connected to the rear high-pressure telescopic straight pipe section 15. It is connected to the flowmeter under test 24 through the rear connection device fixing bolt 26, and the working liquid flowing out of the flowmeter under test 24 is introduced into the standard high-pressure flowmeter 19.

[0044] Standard high-pressure flowmeter 19: It monitors the flow rate of the working liquid flowing through the calibration system in real time. The servo flow regulator 3 automatically adjusts the output flow rate of the working liquid according to the feedback value of the standard high-pressure flowmeter 19 and the set value of the full-parameter display controller 42.

[0045] Servo pressure regulator 20: It loads the working liquid flowing through the flowmeter under test 24 according to the setting of the full-parameter display controller 42, so that the pressure value measured by the front-end pressure and temperature sensor 16 reaches the set value of the full-parameter display controller 42, in order to evaluate the accuracy of the flowmeter under test 24 at the set pressure or calibrate its coefficient value at the set pressure.

[0046] Three-way servo commutator 21: Its function is to control the working liquid in the calibration circuit to flow back to the fuel tank through the commutator return pipe 22 or flow to the weighing fuel tank 31 of the weighing calibration system according to the set requirements of the full-parameter display controller 42 after the pressure value measured by the front-end pressure and temperature sensor 16 and the flow rate value measured by the high-pressure flowmeter 19 are stable for the working liquid pressurized by the servo pressure regulator 20. And after the amount of liquid flowing into the weighing fuel tank 31 reaches the set value, the flow direction of the working liquid is switched back to the fuel tank.

[0047] IV. Working liquid weighing and metering system This system consists of a weighing fuel tank 31, an on-line densitometer 32, an electric drain valve 33, a weighing sensor 35, a weighing bracket 36, metering liquid 37, a fuel tank cover 38, and a weighing tank temperature sensor 40 as shown in the figure. The outside of the weighing fuel tank 31 is connected to the weighing sensor 35 below through the weighing bracket 36. A weighing tank temperature sensor 40 is installed on the upper wall of the weighing fuel tank 31. The lower part of the weighing tank temperature sensor 40 is immersed in the metering liquid 37. An on-line densitometer 32 is also provided above the metering liquid 37. The main function of the system is to measure the volume of the working liquid 9 flowing through the flowmeter under test 24 within the metering time by the weighing method.

[0048] Functions of each component of this system: Weighing fuel tank 31: The bottom is of a conical structure to facilitate the discharge of the metering liquid 37 after weighing. An on-line densitometer 32, a weighing tank temperature sensor 40, and an electric drain valve 33 are installed inside it, and it is fixed on the weighing sensor 35 through the weighing bracket 36.

[0049] V. Process control system: It includes a controller bracket 41, a full-parameter display and control instrument 42, a system preparation button 43, a preparation completion indicator light 44, a test start button 45, and a test completion indicator light 46. A three-way servo commutator 21, an electric drain valve 33, a load cell 35, an on-line densitometer 32, a fuel tank temperature sensor 39, a weighing tank temperature sensor 40, a front-end pressure and temperature sensor 16, a rear-end pressure and temperature sensor 17, a flowmeter under test 24, a standard high-pressure flowmeter 19, a variable-frequency speed-regulating motor 1, a servo flow regulator 3, and a servo pressure regulator 20 are all connected to the full-parameter display and control instrument 42.

[0050] Functions of each component:

[0051] Full-parameter display and control instrument 42: By collecting the front-end temperature and pressure of the front-end pressure and temperature sensor 16, the rear-end pressure and temperature sensor 17, the on-line densitometer 32, the fuel tank temperature sensor 39, the weighing tank temperature sensor 40, the standard high-pressure flowmeter 19, and the load cell 35, the measurement of pressure, temperature, flow rate, weight, and density can be realized. By controlling the variable-frequency speed-regulating motor 1 and the servo flow regulator 3, the adjustment and control of the output flow rate can be achieved. By controlling the servo pressure regulator 20, the control of the pressure of the calibration system can be realized; by controlling the three-way servo commutator 21 and the electric drain valve 33, the control of the flow direction of the working liquid during the test and the draining operation can be realized. By collecting the signals of the flowmeter under test 24 and combining the return values of the sensors, functions such as instantaneous flow rate collection, cumulative flow rate and pulse number collection, time measurement, data operation, and storage can be realized.

[0052] A calibration device for a high-pressure oil flowmeter, and its working method process is as follows:

[0053] Step 1. Installation implementation of the flowmeter under test: Select a front connection device 27, a rear connection device 28, front connection device bolts 25, and rear connection device bolts 26 that match the inlet and outlet of the flowmeter under test 24, and fix the flowmeter under test 24 in the calibration circuit.

[0054] Step 2. System preparation implementation: The purposes to be achieved during the system preparation process are: to keep the temperature of the oil-based working liquid 9 constant at the standard working temperature, to adjust the output flow rate of the servo variable piston pump 2 to the calibration flow rate, to position the three-way servo commutator 21 in the return liquid state, and to close the electric drain valve after emptying the weighing fuel tank 31.

[0055] The implementation process is as follows: First, after inputting the basic parameters of the flowmeter under test 24, such as verification and calibration pressure, flow rate, working liquid temperature, etc., into the full-parameter display controller 42, press the system preparation button 43. At this time, the program of the full-parameter display controller 42 first judges the return value of the fuel tank temperature sensor 39 and compares it with the set value on the parameter display controller 42. If it is greater than the set value, the water-cooled cooler 12 is automatically started for cooling until the temperature is the same as the set value. If it is lower than the set value, the heating device 10 is started to heat the oil until the return value of the fuel tank temperature sensor 39 is the same as the set value on the parameter display controller 42 and then stops.

[0056] Meanwhile, judge the opening and closing state of the electric drain valve 33. If it is in the closed state, it will be automatically opened until the return value of the load cell 35 is consistent with the no-load value set in the full-parameter display controller 42, then it is closed and the load cell value is set to zero.

[0057] Judge the position state of the three-way servo commutator 21 and set it to the return liquid state.

[0058] When the return value of the temperature sensor 39 is the same as the set value on the parameter display controller 42, the return value of the load cell 35 is consistent with the no-load value set in the full-parameter display controller 42, the electric drain valve 33 is in the closed state, and the three-way servo commutator 21 is set to the return liquid state, the full-parameter display controller 42 will start the variable-frequency speed-regulating motor 1 and limit its speed to 80% of the rated speed through the full-parameter display controller 42. Then, gradually increase the control voltage of the servo flow regulator 3 to gradually increase the output flow rate of the servo variable piston pump 2. At the same time, detect the return value of the standard high-pressure flowmeter 19 and compare it with the flow rate value set in the full-parameter display controller 42 until they are consistent. At this time, the system preparation is completed, and the preparation completion indicator light 44 is on.

[0059] The flow direction of the working liquid in this state: fuel tank 7 — suction filter 8 — suction pipe 29 — servo variable piston pump 2 — high-pressure gas precipitation device 18 — front telescopic high-pressure straight pipe section 14 — front connection device 27 — flowmeter under test 24 — rear connection device 28 — rear telescopic high-pressure straight pipe section 15 — standard high-pressure flowmeter 19 — servo pressure regulator 20 — return liquid position of the three-way servo commutator 21 — return liquid pipe 22 — fuel tank 7

[0060] Step 3. System calibration process: After the system is prepared, it does not shut down. When the test start button 45 is pressed, the full-parameter display controller 42 starts to output a loading signal to the servo pressure regulator 20 until the return value of the front-end pressure and temperature sensor 16 matches and remains the same as the set value of the full-parameter display controller 42. At this time, the return value of the secondary detection standard high-pressure flow meter 19 is compared with the flow value set in the full-parameter display controller 42. If it is lower than the set value, the speed of the variable-frequency speed-regulating motor 1 is increased; if it is higher than the set value, the speed of the variable-frequency speed-regulating motor 1 is decreased until the return value of the standard high-pressure flow meter 19 matches the flow value set in the full-parameter display controller 42.

[0061] After the return value of the front-end pressure and temperature sensor 16 matches the set value of the full-parameter display controller 42 and the return value of the standard high-pressure flow meter 19 matches the flow value set in the full-parameter display controller 42 and remains so for 1 minute, the test program is started. At this time, the full-parameter display controller 42 starts timing and starts measuring the instantaneous flow value and cumulative pulse count returned by the flow meter under test 24. At the same time, the three-way servo commutator 21 is positioned at the working position. At this time, the flow direction of the working liquid is: oil tank 7 — suction filter 8 — suction pipe 29 — servo variable piston pump 2 — high-pressure gas precipitation device 18 — front-end telescopic high-pressure straight pipe section 14 — front connection device 27 — flow meter under test 24 — rear connection device 28 — rear-end telescopic high-pressure straight pipe section 15 — standard high-pressure flow meter 19 — servo pressure regulator 20 — working position of the three-way servo commutator 21 — liquid outlet pipe 23 of the commutator — weighing oil tank 31

[0062] At this time, the working liquid enters the weighing oil tank 31 through the above channels. When the return value of the weighing sensor 35 reaches the full-load set value of the weighing tank, the recording of the instantaneous flow value and cumulative pulse count returned by the flow meter under test 24 is stopped, and the time, pressure, weight of the metering liquid 37 flowing into the weighing tank, and the return values of the weighing tank temperature sensor 40 and the on-line densitometer 32 are saved. At the same time, the three-way servo commutator 21 is positioned at the return liquid level, the variable-frequency speed-regulating motor 1 is stopped, the servo flow regulator 3 is set to zero, and the servo pressure regulator 20 is set to zero. One test is completed.

[0063] The full-parameter display controller 42 calculates the volume V of the metering liquid 37 based on the weight detected by the weighing sensor 35 and the density value returned by the on-line densitometer 32 recorded at the end point of the test, and the recorded inflow time T, and then calculates the standard real-time flow rate. By comparing it with the real-time flow rate measured by the flow meter under test 24 recorded, the measurement accuracy level of the flow meter under test 24 at the set pressure and temperature can be calculated. The pulse equivalent is calculated through the volume V and the pulse count returned by the flow meter under test 24 during the recorded test time T, and the parameter calibration is completed.

[0064] Step 4, implementation of oil drainage of the weighing system: The metered liquid 37 after metering and weighing shall be returned to the fuel tank 7 after weighing. After starting the liquid drainage process, first, the full-parameter display controller 42 detects the return value of the weighing sensor 35. If it is greater than the no-load value, the electric liquid drainage valve 33 is placed in the open position, and the metered liquid 37 flows into the manifold pipe 34 through the electric liquid drainage valve 33 and returns to the fuel tank 7. After the return value of the weighing sensor 35 reaches the set no-load value, the electric liquid drainage valve 33 is placed in the switch position to complete one oil drainage process.

[0065] Note that the above is only the preferred embodiment of the present invention and the technical principles applied. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein. Various obvious changes, re-adjustments, and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments. Without departing from the concept of the present invention, more other equivalent embodiments can be included, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A verification and calibration system for a high-pressure oil flowmeter, characterized in that, It includes an adjustable stepless variable high-pressure liquid supply device, a working liquid parameter guarantee system, a working liquid transportation control and test flowmeter clamping system, a working liquid weighing and metering system, and a process control system. The adjustable stepless variable high-pressure liquid supply device includes a variable-frequency motor, a servo variable plunger pump, a servo flow regulator, and a coupling. The variable-frequency motor is connected to the servo variable plunger pump through the coupling. The servo flow regulator is arranged on the servo variable plunger pump. The servo variable plunger pump is connected to the working liquid parameter guarantee system through a suction pipe and extracts the working liquid in the working liquid parameter guarantee system. The working liquid transportation control and test flowmeter clamping system includes a high-pressure gas precipitation device, a test flowmeter, a standard high-pressure flowmeter, and a servo pressure regulator. The high-pressure gas precipitation device is connected to the front end of the test flowmeter through a front-end high-pressure telescopic straight pipe section. The rear end of the test flowmeter is connected to the standard high-pressure flowmeter through a rear-end high-pressure straight pipe section. The other end of the standard high-pressure flowmeter is connected to the servo pressure regulator. The servo pressure regulator is connected with a commutator return pipe and a commutator outlet pipe through a three-way servo commutator. The commutator return pipe is connected to the rear part of the working liquid parameter guarantee system. The commutator outlet pipe is connected to the upper part of the working liquid weighing and metering system. The lower part of the working liquid weighing and metering system is connected to the working liquid parameter guarantee system. The servo variable plunger pump and the three-way servo commutator are connected to the process control system for control. The front end of the test flowmeter is connected to the front-end high-pressure telescopic straight pipe section through a front connection device and a front connection device fixing bolt. The rear end of the test flowmeter is connected to the standard high-pressure flowmeter through a rear connection device fixing bolt and a rear connection device. The test flowmeter and the standard high-pressure flowmeter are connected to the process control system. A front-end pressure and temperature sensor is installed at the front end above the front-end high-pressure telescopic straight pipe section, and a rear-end pressure and temperature sensor is installed at the rear end above the rear-end high-pressure straight pipe section. The front-end pressure and temperature sensor and the rear-end pressure and temperature sensor are connected to the process control system for control.

2. The verification and calibration system of a high-pressure oil flowmeter according to claim 1, characterized in that, The working liquid parameter guarantee system includes an oil tank, a heating device, a magnetic filter, and an oil tank temperature sensor. The oil tank is filled with working liquid. An oil suction filter is installed on the inner wall of the oil tank at the corresponding position of the suction pipe for extracting the working liquid through the oil suction filter. The heating device and the oil tank temperature sensor are fixed on the oil tank cover. The lower part of the heating device is immersed in the working liquid. The magnetic filter is arranged in the oil tank behind the heating device. The servo variable plunger pump is connected to the oil tank through a suction pipe.

3. The verification and calibration system of a high-pressure oil flowmeter according to claim 2, characterized in that, The oil tank is also provided with an anti-foaming net and a water-cooled cooler. The anti-foaming net is arranged on both sides of the magnetic filter, and the water-cooled cooler is arranged at the lower part of the oil tank.

4. The calibration system for a high-pressure oil flowmeter according to claim 1, characterized in that, The working liquid weighing and metering system includes a weighing fuel tank, an on-line densitometer, an electric drain valve, and a weighing tank temperature sensor. The weighing fuel tank is filled with metering liquid. The outer side of the weighing fuel tank is connected to the weighing sensor below through a weighing bracket. The upper wall of the weighing fuel tank is equipped with a weighing tank temperature sensor. The lower part of the weighing tank temperature sensor is immersed in the metering liquid. An on-line densitometer is also provided above the metering liquid. The electric drain valve, the weighing sensor, the on-line densitometer, the fuel tank temperature sensor, and the weighing tank temperature sensor are connected to the process control system.

5. The calibration system for a high-pressure oil flowmeter according to claim 4, wherein, The central part of the lower part of the weighing fuel tank is inserted and connected to the working liquid parameter guarantee system through an electric drain valve and a manifold pipe.

6. The calibration system for a high-pressure oil flowmeter according to claim 1, wherein, The process control system includes a full-parameter display and control instrument, a system preparation button, a preparation completed indicator light, a test start button, and a test completed indicator light installed on a controller bracket. The full-parameter display and control instrument is used to control each device connected to it in the system.

7. The calibration system for a high-pressure oil flowmeter according to claim 1, characterized in that, The servo variable plunger pump is fixed on the base through a pump bracket.

8. The working method of a verification and calibration system for a high-pressure oil flowmeter according to claim 1, characterized in that, It includes the following steps: Step 1: Installation implementation of the flowmeter under test: Select a front connection device, a rear connection device, front connection device bolts, and rear connection device bolts that match the inlet and outlet of the flowmeter under test, and fix the flowmeter under test in the calibration circuit. Step 2: System preparation implementation: Keep the temperature of the oil-based working liquid constant at the standard working temperature, adjust the output flow of the servo variable plunger pump to the calibration flow, place the three-way servo commutator in the return liquid state, empty the weighing fuel tank and then place the electric drain valve in the closed state. Step 3: System calibration process: After the system preparation is completed, the system does not stop. When the test start button is pressed, the full-parameter display and control instrument starts to output a loading signal to the servo pressure regulator until the return value of the front-end pressure and temperature sensor matches and remains the same as the set value of the full-parameter display and control instrument. At this time, the return value of the secondary detection is compared with the flow value set in the full-parameter display and control instrument to complete parameter calibration. Step 4: Oil draining implementation of the weighing system: After the metering liquid is weighed, it is returned to the fuel tank after weighing. After starting the draining process, first, the full-parameter display and control instrument detects the return value of the weighing sensor. If it is greater than the no-load value, the electric drain valve is placed in the open position, and the metering liquid flows into the manifold pipe through the electric drain valve and returns to the fuel tank. After the return value of the weighing sensor reaches the set no-load value, the electric drain valve is placed in the open and closed position to complete one oil draining process.

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