Testing device for r744 supercritical and subcritical valves
By combining parallel compression components and air coolers, the problem of existing equipment being unable to quickly and stably control valve temperature and pressure is solved, enabling efficient and accurate valve testing and supporting reverse testing without disassembly.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- CHINA NAT ELECTRIC APP RES INST
- Filing Date
- 2024-12-05
- Publication Date
- 2026-05-28
AI Technical Summary
Existing valve testing equipment cannot quickly and stably control the refrigerant inlet temperature, inlet and outlet pressure, and refrigerant flow rate of the valve under test. Furthermore, reverse testing requires frequent disassembly and reassembly, resulting in a narrow control range and poor stability.
It adopts a combined structure of parallel compression components, testing components and auxiliary components, and connects the compressor and air cooler in series. It uses pneumatic ball valves and regulating valves to control the flow of refrigerant, so as to achieve rapid and stable testing of valve components.
It enables high-flow testing of valve components under high-pressure conditions, improving flow control accuracy and stability. It also supports reverse testing without disassembly, thus improving testing efficiency and accuracy.
Smart Images
Figure CN2024137156_28052026_PF_FP_ABST
Abstract
Description
A testing device for supercritical and subcritical valves that meets R744 standards Technical Field
[0001] This invention belongs to the field of refrigeration system valve testing technology, and in particular relates to a testing device for supercritical and subcritical valves that meets R744 standards. Background Technology
[0002] With the ongoing global trend of replacing conventional refrigerants with environmentally friendly ones, the natural refrigerant R744 (carbon dioxide) is being widely used in large supermarkets, cold storage facilities, and new energy vehicles. However, because its operating pressure is 5-10 times higher than that of conventional refrigerants, with an operating pressure range of 5-15 MPa and an exhaust temperature reaching 130℃, all components within the refrigeration system require new development. Valves (including expansion valves, solenoid valves, and three-way valves) are crucial components of the refrigeration system; their flow performance, flow resistance, stability, durability, and noise levels significantly impact the overall system efficiency. Therefore, comprehensive and highly stable testing equipment is urgently needed to test them.
[0003] Currently, major refrigeration system manufacturers have increased their efforts in matching tests of compressors and valves. The expansion valve, as a crucial component, automatically regulates refrigerant flow to ensure the refrigeration system maintains optimal operating conditions, accelerating cooling, precisely controlling temperature, and achieving energy savings. However, due to the limited practical application of R744 as a refrigerant, the corresponding testing equipment is primarily built based on actual usage systems, as shown in Figure 1 (the original test system diagram). This type of testing equipment suffers from poor stability in operating condition control, slow stabilization speed, and a narrow control range. Testing the expansion valve mainly requires controlling the temperature, pressure, and refrigerant flow rate before and after the refrigerant end of the expansion valve. The aforementioned test system diagram... The flow rate is controlled solely by the compressor's frequency converter. However, due to the limited frequency conversion range and large adjustment amplitude of a single-stage compressor, the flow control range is small and the stability is poor. Furthermore, the high-pressure control, achieved through water flow or temperature control on the air cooler side, results in slow control speed. Additionally, some valves require reverse flow testing during durability or performance testing, but the aforementioned testing equipment lacks this capability, necessitating valve removal and reversal for testing. This is unsuitable for durability tests that require repeated flow direction changes. Finally, when testing high-temperature inlet conditions, the inlet temperature is controlled by the compressor's exhaust temperature, which in turn depends on the intake superheat, leading to stability issues and a narrow control range.
[0004] Existing valve testing equipment cannot quickly and stably control the refrigerant inlet temperature, inlet and outlet pressure, and refrigerant flow rate of the valve under test, failing to meet the requirements for rapid and stable operation. Furthermore, valves require frequent disassembly and reassembly for reverse testing, which is quite cumbersome. Therefore, this invention proposes a testing device for supercritical and subcritical valves that meets the requirements of R744. Summary of the Invention
[0005] The purpose of this invention is to provide a testing device for supercritical and subcritical valves that meets the requirements of R744, solving the problem that existing valve testing equipment cannot quickly and stably control the refrigerant inlet temperature, inlet and outlet pressure, and refrigerant flow rate of the valve under test, thus failing to meet the requirements of rapid and stable operation. At the same time, the valve requires frequent disassembly and assembly when performing reverse testing, which is quite troublesome.
[0006] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution:
[0007] The present invention is a testing device for supercritical and subcritical valves that meets R744 requirements, comprising a parallel compression assembly, a testing assembly, and an auxiliary assembly. The testing assembly is connected in series with the parallel compression assembly at both ends, and the auxiliary assembly is connected in series with the testing assembly.
[0008] The parallel compression assembly includes a primary compressor and a secondary compressor connected in parallel. The inlet and outlet ends of the parallel circuit formed by the primary compressor and the secondary compressor are respectively connected to a gas separator and an oil separator. A first air cooler is also connected between the primary compressor and the secondary compressor.
[0009] The test assembly includes a condenser and a second air cooler. The oil separator refrigerant outlet is connected to both the condenser and the second air cooler via a tee connector. The condenser refrigerant outlet is connected to a liquid storage tank. The liquid storage tank refrigerant outlet is connected to the inlet of the second air cooler via a refrigerant pipe. The second air cooler is connected in sequence to an oil heater, the valve under test, and a second evaporator via a refrigerant pipe. The second evaporator is connected to the gas separator refrigerant inlet via a refrigerant pipe to form a loop.
[0010] Preferably, the auxiliary components include a first evaporator, the refrigerant inlet of the first evaporator being connected to the outlet of the liquid storage tank via a refrigerant pipeline, and the refrigerant outlet of the first evaporator being connected to the refrigerant pipeline between the second evaporator and the gas separator; a regulating valve UNW3 is installed on the refrigerant pipeline between the first evaporator and the liquid storage tank.
[0011] Preferably, the first-stage compressor inlet is equipped with a pneumatic ball valve UNS1, and the first-stage compressor outlet is equipped with a temperature control point TWS2 and a pneumatic ball valve UNS2; the second-stage compressor inlet is equipped with a pneumatic ball valve UNS4 and a temperature control point TIS3, and the second-stage compressor outlet is equipped with a temperature control point TWS4 and a pneumatic ball valve UNS1; a pneumatic ball valve UNS25 is installed on the refrigerant pipeline at the first air cooler inlet; the refrigerant pipeline at the first air cooler inlet is connected between the temperature control point TWS2 and the pneumatic ball valve UNS2; a pneumatic ball valve UNS26 is installed on the refrigerant pipeline at the first air cooler outlet; and the refrigerant pipeline at the first air cooler outlet is connected between the pneumatic ball valve UNS4 and the temperature control point TIS3.
[0012] Preferably, a pressure control point PSE1 and a temperature control point TIS1 are provided at the gas outlet end of the gas separator; the oil return end of the oil separator is connected to the first-stage compressor and the second-stage compressor respectively through two oil return pipes.
[0013] Preferably, a regulating valve UNW5 is installed on the refrigerant pipeline between the condenser and the oil separator, and a pneumatic ball valve UNS28 is connected in parallel at both the inlet and outlet ends of the regulating valve UNW5; a pneumatic ball valve UNS13 is installed on the refrigerant pipeline between the second air cooler and the oil separator; a pneumatic ball valve UNS29 is installed on the refrigerant pipeline between the liquid storage tank and the second air cooler, and the refrigerant pipeline is connected between the pneumatic ball valve UNS13 and the second air cooler;
[0014] A temperature control point TIS10 is provided between the second air cooler and the oil heater. A pneumatic ball valve UNS19, a temperature control point TIS6, a pressure control point PSE6, a valve under test, a temperature control point TIS7, a pressure control point PSE7, a pneumatic ball valve UNS20, and a regulating valve UNW1 are sequentially installed on the refrigerant pipeline between the outlet of the oil heater and the second evaporator. A pneumatic ball valve UNS15 is connected in parallel between the inlet of pneumatic ball valve UNS19 and the inlet of pneumatic ball valve UNS20. A pneumatic ball valve UNS16 is connected in parallel between the outlet of pneumatic ball valve UNS19 and the outlet of pneumatic ball valve UNS20. A temperature control point TIS5 and a pneumatic ball valve UNS14 are respectively provided at the outlet of the second evaporator.
[0015] Preferably, the parameters to be controlled for the performance test of the valve under test include the following: valve inlet pressure PSE6: controlled by the condenser during subcritical testing and by the regulating valve UNW5 during supercritical testing; valve inlet temperature TIS6: controlled by the second air cooler and the oil heater; valve outlet pressure PSE6: controlled by the regulating valve UNW3.
[0016] The parameters that need to be controlled for the flow obstruction test sample of the valve under test include the following: valve inlet pressure PSE6: controlled by the condenser during subcritical testing and by the regulating valve UNW5 during supercritical testing; valve inlet temperature TIS6: controlled by the second air cooler and the oil heater; valve outlet pressure PSE6: controlled by the regulating valve UNW1.
[0017] Preferably, when testing the valve under subcritical positive conditions, the primary compressor and the secondary compressor are kept in parallel, and the pneumatic ball valve UNS13, regulating valve UNW5, pneumatic ball valve UNS15, and pneumatic ball valve UNS16 are closed. The refrigerant enters the test assembly from the parallel compression assembly and flows sequentially through the pneumatic ball valve UNS28, condenser, liquid receiver, pneumatic ball valve UNS29, second air cooler, oil heater, pneumatic ball valve UNS19, temperature control point TIS6, pressure control point PSE6, the valve under test, temperature control point TIS7, pressure control point PSE7, pneumatic ball valve UNS20, regulating valve UNW1, and the second evaporator until the gas separation completes one loop.
[0018] Preferably, when testing the valve under subcritical reverse conditions, the primary compressor and the secondary compressor are kept in parallel, and the pneumatic ball valve UNS13, regulating valve UNW5, pneumatic ball valve UNS19, and pneumatic ball valve UNS20 are closed. The refrigerant enters the test assembly from the parallel compression assembly and flows sequentially through the pneumatic ball valve UNS28, condenser, liquid receiver, pneumatic ball valve UNS29, second air cooler, oil heater, pneumatic ball valve UNS15, pressure control point PSE7, temperature control point TIS7, the valve under test, pressure control point PSE6, temperature control point TIS6, pneumatic ball valve UNS16, regulating valve UNW1, and the second evaporator until the gas separation completes one loop.
[0019] Preferably, when testing the valve under supercritical positive conditions, the primary compressor and the secondary compressor are kept in parallel, and pneumatic ball valves UNS28, UNS29, UNS15, and UNS16 are closed. The refrigerant is discharged from the parallel compression assembly and divided into two liquid paths. In one liquid path, the refrigerant flows sequentially through regulating valve UNW5, condenser, liquid receiver, and first evaporator until the gas separation completes one loop. In the other liquid path, the refrigerant flows sequentially through pneumatic ball valve UNS13, second air cooler, oil heater, pneumatic ball valve UNS19, temperature control point TIS6, pressure control point PSE6, the valve under test, temperature control point TIS7, pressure control point PSE7, pneumatic ball valve UNS20, regulating valve UNW1, and second evaporator until the gas separation completes one loop.
[0020] Preferably, when testing the valve under supercritical positive conditions, the primary compressor and the secondary compressor are kept in parallel, and pneumatic ball valves UNS28, UNS29, UNS19, and UNS20 are closed. The refrigerant is discharged from the parallel compression assembly and divided into two liquid paths. In one liquid path, the refrigerant flows sequentially through regulating valve UNW5, condenser, liquid tank, and first evaporator until the gas separation completes a loop. In the other liquid path, the refrigerant flows sequentially through pneumatic ball valve UNS13, second air cooler, oil heater, pneumatic ball valve UNS15, pressure control point PSE7, temperature control point TIS7, the valve under test, pressure control point PSE6, temperature control point TIS6, pneumatic ball valve UNS16, regulating valve UNW1, and second evaporator until the gas separation completes a loop.
[0021] The present invention has the following beneficial effects:
[0022] 1. This invention improves the operating range of the compressor across critical conditions by setting the compressor in a series-parallel configuration, meeting the requirements of high pressure ratio conditions. In the series mode, multiple compressors can be used in parallel at each stage to meet the high flow rate testing requirements under high pressure ratio conditions. At the same time, the inlet temperature can be controlled over a wide range by using air cooling and oil heating. Through compressor frequency conversion and auxiliary component bypass flow control, energy saving is achieved while meeting the requirements of large flow range and operating condition stability.
[0023] 2. This invention achieves precise control of the refrigerant flow in the test circuit by setting up two variable frequency compressors and using the UNW3 regulating valve in the auxiliary circuit component to control the refrigerant flow. The primary and secondary compressors are selected to operate at high, medium, and low frequencies to fix the approximate total refrigerant flow of the system. The refrigerant flow is then diverted through the UNW3 regulating valve in the auxiliary circuit.
[0024] 3. This invention controls the compressor exhaust pressure by adjusting the opening of the regulating valve UNW5, thereby controlling the inlet pressure PSE6 of the tested valve. Because the regulating valve has a fast opening response, it is faster and more direct than the original method of adjusting the condenser water circuit temperature or flow rate.
[0025] 4. In this invention, since the single-stage compressor has its own operating range limitation, and under supercritical operating conditions, the operating pressure ratio required for testing the valve under test will exceed the operating range of the compressor under some heat pump conditions, in order to avoid the compressor exhaust temperature being too high and to ensure reliable operation of the compressor, two auxiliary compressors are connected in series to operate in relay mode. At this time, the auxiliary compressor MCM1 is the first-stage compressor (low-pressure stage) and the auxiliary compressor MCM2 is the high-pressure stage. The exhaust of the first-stage compressor is cooled by the first air cooler and then enters the suction end of the second-stage compressor to achieve high-pressure ratio operation.
[0026] 5. In this invention, pneumatic ball valves UNS15, UNS16, UNS19, and UNS20 switch on and off according to the flow direction of the valve under test. When testing forward flow, pneumatic ball valves UNS15 and UNS16 are closed, and pneumatic ball valves UNS19 and UNS20 are open. When testing reverse flow, pneumatic ball valves UNS15 and UNS16 are open, and pneumatic ball valves UNS19 and UNS20 are closed. This ensures that the inlet and outlet flow directions of the valve under test are automatically switched without disassembling the valve under test. This is beneficial for frequent switching tests in both forward and reverse directions during durability testing, and also enables performance testing of the valve under test without disassembling it.
[0027] 6. In this invention, the condenser inlet temperature is controlled by the second air cooler and the oil heater. When the inlet temperature is low or medium, it is pre-cooled by the second air cooler or directly controlled. When the temperature is extremely high, it is directly controlled by the oil heater. This can achieve a wide range of inlet temperature control up to 160°C. Attached Figure Description
[0028] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0029] Figure 1 is a schematic diagram of the testing principle of existing supercritical valves;
[0030] Figure 2 is a general diagram of the R744 supercritical and subcritical heat exchanger testing device provided by the present invention.
[0031] Figure 3 is a diagram of the compressors operating in parallel in this invention;
[0032] Figure 4 is a diagram of the compressor operating in series in this invention;
[0033] Figure 5 is a test operation diagram of the subcritical positive valve provided by the present invention;
[0034] Figure 6 is a test operation diagram of the subcritical reverse valve provided by the present invention;
[0035] Figure 7 is a test operation diagram of the supercritical positive valve provided by the present invention;
[0036] Figure 8 is a test operation diagram of the supercritical reverse valve provided by the present invention.
[0037] The components represented by each number in the attached diagram are listed below: 1. Primary compressor; 2. Secondary compressor; 3. First air cooler; 4. Oil separator; 5. Gas separator; 6. Condenser; 7. Second air cooler; 8. Oil heater; 9. First evaporator; 10. Second evaporator; 11. Liquid receiver; 12. Valve under test. Detailed Implementation
[0038] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.
[0039] Referring to Figures 1-3, the present invention is a testing device for supercritical and subcritical valves that meets R744 requirements, including a parallel compression assembly, a testing assembly, and an auxiliary assembly. The testing assembly is connected in series with the parallel compression assembly at both ends, and the auxiliary assembly is connected in series with the testing assembly.
[0040] The parallel compression assembly includes a primary compressor 1 and a secondary compressor 2 connected in parallel. The inlet and outlet ends of the parallel circuit formed by the primary compressor 1 and the secondary compressor 2 are respectively connected to a gas separator 5 and an oil separator 4. A first air cooler 3 is also connected between the primary compressor 1 and the secondary compressor 2. The primary compressor 1 and the secondary compressor 2 are used to provide refrigerant flow to the test system, thereby establishing a system operating pressure difference. The first air cooler 3 is used to control the suction temperature of the secondary compressor 2 when the compressors are connected in series. The oil separator 4 is used to separate the compressor oil from the refrigerant discharged from the two compressors and return it to the compressor through a return oil pipe. The gas separator is used to protect the compressor suction from liquid contamination.
[0041] The test assembly includes a condenser 6 and a second air cooler 7. The refrigerant outlet of the oil separator 4 is connected to the condenser 6 and the second air cooler 7 respectively via a tee connector. The refrigerant outlet of the condenser 6 is connected to the liquid storage tank 11. The refrigerant outlet of the liquid storage tank 11 is connected to the inlet of the second air cooler 7 via a refrigerant pipe. The second air cooler 7 is connected in sequence to the oil heater 8, the valve under test 12, and the second evaporator 10 via a refrigerant pipe. The second evaporator 10 is connected to the refrigerant inlet of the gas separator 5 to form a loop.
[0042] The auxiliary components include a first evaporator 9, the refrigerant inlet of the first evaporator 9 is connected to the outlet of the liquid storage tank 11 through a refrigerant pipe, and the refrigerant outlet of the first evaporator 9 is connected to the refrigerant pipe between the second evaporator 10 and the gas separator 5; a regulating valve UNW3 is installed on the refrigerant pipe between the first evaporator 9 and the liquid storage tank 11.
[0043] Specifically, the first-stage compressor 1 is equipped with a pneumatic ball valve UNS1 at its inlet and a temperature control point TWS2 and a pneumatic ball valve UNS2 at its outlet; the second-stage compressor 2 is equipped with a pneumatic ball valve UNS4 and a temperature control point TIS3 at its inlet and a temperature control point TWS4 and a pneumatic ball valve UNS1 at its outlet; the first air cooler 3 is equipped with a pneumatic ball valve UNS25 on its refrigerant pipeline at its inlet; the refrigerant pipeline at the inlet of the first air cooler 3 is connected between the temperature control point TWS2 and the pneumatic ball valve UNS2; the first air cooler 3 is equipped with a pneumatic ball valve UNS26 on its refrigerant pipeline at its outlet; and the refrigerant pipeline at the outlet of the first air cooler 3 is connected between the pneumatic ball valve UNS4 and the temperature control point TIS3.
[0044] Among them, the gas separator 5 is equipped with a pressure control point PSE1 and a temperature control point TIS1 at the gas outlet; the oil separator 4 is connected to the first-stage compressor 1 and the second-stage compressor 2 through two oil return pipes.
[0045] Among them, a regulating valve UNW5 is installed on the refrigerant pipeline between the condenser 6 and the oil separator 4, and a pneumatic ball valve UNS28 is connected in parallel at the inlet and outlet ends of the regulating valve UNW5; a pneumatic ball valve UNS13 is installed on the refrigerant pipeline between the second air cooler 7 and the oil separator 4; a pneumatic ball valve UNS29 is installed on the refrigerant pipeline between the liquid storage tank 11 and the second air cooler 7, and the refrigerant pipeline is connected between the pneumatic ball valve UNS13 and the second air cooler 7.
[0046] A temperature control point TIS10 is provided between the second air cooler 7 and the oil heater 8. A pneumatic ball valve UNS19, a temperature control point TIS6, a pressure control point PSE6, a valve under test 12, a temperature control point TIS7, a pressure control point PSE7, a pneumatic ball valve UNS20, and a regulating valve UNW1 are sequentially installed on the refrigerant pipeline between the outlet end of the oil heater 8 and the second evaporator 10. A pneumatic ball valve UNS15 is connected in parallel between the inlet end of the pneumatic ball valve UNS19 and the inlet end of the pneumatic ball valve UNS20. A pneumatic ball valve UNS16 is connected in parallel between the outlet end of the pneumatic ball valve UNS19 and the outlet end of the pneumatic ball valve UNS20. A temperature control point TIS5 and a pneumatic ball valve UNS14 are respectively provided at the outlet end of the second evaporator 10.
[0047] The parameters that need to be controlled for the performance test of the valve 12 under test include the following: valve inlet pressure PSE6: controlled by condenser 6 during subcritical testing and by regulating valve UNW5 during supercritical testing; valve inlet temperature TIS6: controlled by the second air cooler 7 and oil heater 8; valve outlet pressure PSE6: controlled by regulating valve UNW3.
[0048] The parameters that need to be controlled for the flow resistance test sample of valve 12 under test include the following: valve inlet pressure PSE6: controlled by condenser 6 during subcritical testing and by regulating valve UNW5 during supercritical testing; valve inlet temperature TIS6: controlled by the second air cooler 7 and oil heater 8; valve outlet pressure PSE6: controlled by regulating valve UNW1.
[0049] Among them, the pneumatic ball valve is used to switch the refrigerant flow path of the system; the regulating valve is used to adjust the refrigerant flow rate of the corresponding flow path, thereby controlling the temperature and pressure measurement and control points in the system; the condenser 6 controls the intermediate pressure of the system in the supercritical state, and controls the high pressure of the system in the subcritical state; the second air cooler 7 and the oil heater are used to control the temperature before the valve or the inlet temperature of the condenser 6; the first evaporator 9 is used to control the suction superheat of the two compressors; the second evaporator 10 is used to control the refrigerant superheat before the flow meter in the test flow path, ensuring that the flow meter inlet is superheated gaseous refrigerant, and ensuring measurement accuracy; the liquid storage tank 11 is used to store and buffer the amount of refrigerant in the system.
[0050] Example 1
[0051] Referring to Figure 5, when testing the valves under subcritical positive conditions, the primary compressor 1 and the secondary compressor 2 are kept in parallel, and the pneumatic ball valve UNS13, regulating valve UNW5, pneumatic ball valve UNS15, and pneumatic ball valve UNS16 are closed. The refrigerant enters the test assembly from the parallel compression assembly and flows sequentially through the pneumatic ball valve UNS28, condenser 6, liquid receiver 11, pneumatic ball valve UNS29, second air cooler 7, oil heater 8, pneumatic ball valve UNS19, temperature control point TIS6, pressure control point PSE6, the valve under test 12, temperature control point TIS7, pressure control point PSE7, pneumatic ball valve UNS20, regulating valve UNW1, and the second evaporator 10 until the gas separator 5 completes one loop.
[0052] Example 2
[0053] Referring to Figure 6, when testing the valves under subcritical reverse conditions, the primary compressor 1 and the secondary compressor 2 are kept in parallel, and the pneumatic ball valve UNS13, regulating valve UNW5, pneumatic ball valve UNS19, and pneumatic ball valve UNS20 are closed. The refrigerant enters the test assembly from the parallel compression assembly and flows sequentially through the pneumatic ball valve UNS28, condenser 6, liquid receiver 11, pneumatic ball valve UNS29, second air cooler 7, oil heater 8, pneumatic ball valve UNS15, pressure control point PSE7, temperature control point TIS7, the valve under test 12, pressure control point PSE6, temperature control point TIS6, pneumatic ball valve UNS16, regulating valve UNW1, and the second evaporator 10 until the gas separator 5 completes one loop.
[0054] Example 3
[0055] Referring to Figure 7, when testing the valves under supercritical positive conditions, the primary compressor 1 and the secondary compressor 2 are kept in parallel, and pneumatic ball valves UNS28, UNS29, UNS15, and UNS16 are closed. After the refrigerant is discharged from the parallel compression assembly, it is divided into two liquid paths. In one liquid path, the refrigerant flows sequentially through regulating valve UNW5, condenser 6, liquid receiver 11, and first evaporator 9 until the gas separation completes one loop. In the other liquid path, the refrigerant flows sequentially through pneumatic ball valve UNS13, second air cooler 7, oil heater 8, pneumatic ball valve UNS19, temperature control point TIS6, pressure control point PSE6, valve under test 12, temperature control point TIS7, pressure control point PSE7, pneumatic ball valve UNS20, regulating valve UNW1, and second evaporator 10 until the gas separation 5 completes one loop.
[0056] Example 4
[0057] Referring to Figure 8, when testing the valves under supercritical positive conditions, the first-stage compressor 1 and the second-stage compressor 2 are kept in parallel, and pneumatic ball valves UNS28, UNS29, UNS19, and UNS20 are closed. After the refrigerant is discharged from the parallel compression assembly, it is divided into two liquid paths. In one liquid path, the refrigerant flows sequentially through regulating valve UNW5, condenser 6, liquid storage tank 11, and first evaporator 9 until the gas separation completes one loop. In the other liquid path, the refrigerant flows sequentially through pneumatic ball valve UNS13, second air cooler 7, oil heater 8, pneumatic ball valve UNS15, pressure control point PSE7, temperature control point TIS7, the valve under test 12, pressure control point PSE6, temperature control point TIS6, pneumatic ball valve UNS16, regulating valve UNW1, and second evaporator 10 until the gas separation 5 completes one loop.
[0058] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.
Claims
1. A R744 supercritical, subcritical valve element test apparatus satisfying, characterized by: It comprises parallel compression assembly, test assembly and auxiliary assembly, the test assembly is connected with the parallel compression assembly in series, and the auxiliary assembly is connected on the test assembly in series; The parallel compression assembly comprises a first compressor (1) and a second compressor (2) connected in parallel, and a gas separator (5) and an oil separator (4) are respectively connected to both ends of the parallel circuit formed by the first compressor (1) and the second compressor (2); a first gas cooler (3) is further connected between the first compressor (1) and the second compressor (2). The test assembly comprises a condenser (6) and a second gas cooler (7), the oil separator (4) is connected to the condenser (6) and the second gas cooler (7) through a three-way joint, the condenser (6) is connected to a liquid storage tank (11), the liquid storage tank (11) is connected to the second gas cooler (7) through a refrigerant pipeline, the second gas cooler (7) is connected to an oil heater (8), a measured valve (12) and a second evaporator (10) in sequence through a refrigerant pipeline, and the second evaporator (10) is connected to the gas separator (5) through a refrigerant pipeline to form a circuit.
2. A device for testing a valve element for R744 supercritical and subcritical conditions according to claim 1, characterized in that The auxiliary assembly comprises a first evaporator (9), the first evaporator (9) is connected to the liquid storage tank (11) through a refrigerant pipeline, and the first evaporator (9) is connected to a refrigerant pipeline between the second evaporator (10) and the gas separator (5); an adjusting valve UNW3 is installed on the refrigerant pipeline between the first evaporator (9) and the liquid storage tank (11).
3. A device for testing a valve element for R744 supercritical and subcritical conditions according to claim 2, characterized in that A pneumatic ball valve UNS1 is arranged at the gas inlet end of the first compressor (1), a temperature measuring and control point TWS2 and a pneumatic ball valve UNS2 are arranged at the gas outlet end of the first compressor (1), a pneumatic ball valve UNS4 and a temperature measuring and control point TIS3 are arranged at the gas inlet end of the second compressor (2), a temperature measuring and control point TWS4 and a pneumatic ball valve UNS1 are arranged at the gas outlet end of the second compressor (2), a pneumatic ball valve UNS25 is arranged on the refrigerant pipeline at the gas inlet end of the first gas cooler (3), the refrigerant pipeline at the gas inlet end of the first gas cooler (3) is connected between the temperature measuring and control point TWS2 and the pneumatic ball valve UNS2, a pneumatic ball valve UNS26 is arranged on the refrigerant pipeline at the gas outlet end of the first gas cooler (3), and the refrigerant pipeline at the gas outlet end of the first gas cooler (3) is connected between the pneumatic ball valve UNS4 and the temperature measuring and control point TIS3.
4. A device for testing a valve element according to claim 3, wherein A pressure measuring and control point PSE1 and a temperature measuring and control point TIS1 are arranged at the gas outlet end of the gas separator (5). The oil return end of the oil separator (4) is connected to the first compressor (1) and the second compressor (2) through two oil return pipelines.
5. A device for testing a valve element for R744 supercritical and subcritical conditions according to claim 4, characterized in that The refrigerant pipeline between the condenser (6) and the oil separation (4) is provided with an adjusting valve UNW5, and the adjusting valve UNW5 is connected in parallel with a pneumatic ball valve UNS28 at the inlet and outlet of the gas; the refrigerant pipeline between the second gas cooler (7) and the oil separation (4) is provided with a pneumatic ball valve UNS13; the refrigerant pipeline between the liquid storage tank (11) and the second gas cooler (7) is provided with a pneumatic ball valve UNS29, and the refrigerant pipeline is connected between the pneumatic ball valve UNS13 and the second gas cooler (7); The second gas cooler (7) and the oil heater (8) are provided with a temperature measurement and control point TIS10, and the refrigerant pipeline between the outlet of the oil heater (8) and the second evaporator (10) is sequentially provided with a pneumatic ball valve UNS19, a temperature measurement and control point TIS6, a pressure measurement and control point PSE6, a measured valve (12), a temperature measurement and control point TIS7, a pressure measurement and control point PSE7, a pneumatic ball valve UNS20 and an adjusting valve UNW1; the inlet of the pneumatic ball valve UNS19 and the inlet of the pneumatic ball valve UNS20 are connected in parallel with a pneumatic ball valve UNS15; the outlet of the pneumatic ball valve UNS19 and the outlet of the pneumatic ball valve UNS20 are connected in parallel with a pneumatic ball valve UNS16; and the outlet of the second evaporator (10) is provided with a temperature measurement and control point TIS5 and a pneumatic ball valve UNS14.
6. A device for testing a valve element for R744 supercritical and subcritical conditions according to claim 5, characterized in that The parameters to be controlled in the performance test and the flow resistance test of the measured valve (12) include the following contents: the valve front pressure PSE6 is controlled by the condenser (6) in the subcritical test and by the adjusting valve UNW5 in the supercritical test; the valve front temperature TIS6 is controlled by the second gas cooler (7) and the oil heater (8); wherein the outlet pressure PSE6 of the measured valve (12) in the performance test is controlled by the adjusting valve UNW3; and the outlet pressure PSE6 of the measured valve (12) in the flow resistance test is controlled by the adjusting valve UNW1.
7. A device for testing a valve element for R744 supercritical and subcritical conditions according to claim 6, characterized in that In the valve test under the subcritical positive state, the first compressor (1) and the second compressor (2) remain in parallel state, and the pneumatic ball valve UNS13, the adjusting valve UNW5, the pneumatic ball valve UNS15, the pneumatic ball valve UNS16 are closed, the refrigerant flows through the pneumatic ball valve UNS28, the condenser (6), the liquid storage tank (11), the pneumatic ball valve UNS29, the second gas cooler (7), the oil heater (8), the pneumatic ball valve UNS19, the temperature measurement and control point TIS6, the pressure measurement and control point PSE6, the measured valve (12), the temperature measurement and control point TIS7, the pressure measurement and control point PSE7, the pneumatic ball valve UNS20, the adjusting valve UNW1 and the second evaporator (10) in sequence from the parallel compression assembly to the test assembly to complete a loop.
8. A device for testing a valve element for R744 supercritical and subcritical conditions according to claim 7, characterized in that When the valve is tested under subcritical reverse state, the first compressor (1) and the second compressor (2) are kept in parallel state, and the ball valve UNS13, the regulating valve UNW5, the ball valve UNS19, the ball valve UNS20 are closed, the refrigerant flows through the ball valve UNS28, the condenser (6), the liquid tank (11), the ball valve UNS29, the second air cooler (7), the oil heater (8), the ball valve UNS15, the pressure measuring point PSE7, the temperature measuring point TIS7, the tested valve (12), the pressure measuring point PSE6, the temperature measuring point TIS6, the ball valve UNS16, the regulating valve UNW1 and the second evaporator (10) in sequence to complete a loop.
9. A device for testing a valve element for R744 supercritical and subcritical conditions according to claim 8, characterized in that When the valve is tested under supercritical positive state, the first compressor (1) and the second compressor (2) are kept in parallel state, and the ball valve UNS28, the ball valve UNS29, the ball valve UNS15 and the ball valve UNS16 are closed, the refrigerant is divided into two liquid paths after being discharged from the parallel compression assembly, one of the liquid paths flows through the regulating valve UNW5, the condenser (6), the liquid tank (11) and the first evaporator (9) in sequence to complete a loop, and the other liquid path flows through the ball valve UNS13, the second air cooler (7), the oil heater (8), the ball valve UNS19, the temperature measuring point TIS6, the pressure measuring point PSE6, the tested valve (12), the temperature measuring point TIS7, the pressure measuring point PSE7, the ball valve UNS20, the regulating valve UNW1 and the second evaporator (10) in sequence to complete a loop.
10. A device for testing a valve element for R744 supercritical and subcritical conditions according to claim 9, characterized in that When the valve is tested under supercritical positive state, the first compressor (1) and the second compressor (2) are kept in parallel state, and the ball valve UNS28, the ball valve UNS29, the ball valve UNS19 and the ball valve UNS20 are closed, the refrigerant is divided into two liquid paths after being discharged from the parallel compressionassembly, one of the liquid paths flows through the regulating valve UNW5, the condenser ( 6 ), the liquid tank ( 11 ) and the first evaporator ( 9 ) in sequence to complete a loop, and the other liquid path flows through the ball valve UNS13, the second air cooler ( 7 ), the oil heater ( 8 ), the ball valve UNS15, the pressure measuring point PSE7, the temperature measuring point TIS7, the tested valve ( 12 ), the pressure measuring point PSE6, the temperature measuring point TIS6, the ball valve UNS16, the regulating valve UNW1 and the second evaporator ( 10 ) in sequence to complete a loop.