CN203785876U - A Test Bench for Globe Valves Used in Cryogenic Insulation Gas Cylinders - Google Patents

Abstract

The utility model relates to a stop valve testing stand for a low-temperature heat-insulation gas cylinder. The testing stand comprises a liquid nitrogen tank, a temperature control box, a helium bottle and a Dewar flask, wherein the helium bottle is connected with a tested station in the liquid nitrogen tank successively through a filter, a pressure-reducing valve, a solenoid valve, a first stop valve and a first pressure sensor, the Dewar flask is connected with the liquid nitrogen tank via a second stop valve and with a tested station in the temperature control box via a first solenoid valve and a second pressure sensor, and the tested station in the temperature control box is connected with the second pressure sensor via a second solenoid valve. The testing stand realizes low-temperature start and stop test, low-temperature airtightness test and low-temperature durability test for the stop valve via the liquid nitrogen tank, the temperature control box, the helium bottle and the Dewar flask, and the realization manner is flexible and variable.

Description

A Test Bench for Globe Valves Used in Cryogenic Insulation Gas Cylinders

technical field

The utility model relates to the technical field of shut-off valve testing, in particular to a shut-off valve test bench for low-temperature heat-insulating gas cylinders.

Background technique

Globe valve, also called cut-off valve, is one of the most widely used valves. The reason why it is popular is that the friction between the sealing surfaces is small during the opening and closing process, it is relatively durable, the opening height is not large, and it is easy to manufacture. , easy maintenance, not only suitable for medium and low pressure, but also suitable for high pressure. The closing principle of the globe valve is to rely on the pressure of the valve rod to make the sealing surface of the disc and the sealing surface of the valve seat fit closely to prevent the flow of medium. The stop valve only allows the medium to flow in one direction, and it is directional when installed. The structural length of the stop valve is longer than that of the gate valve, and at the same time, the fluid resistance is large, and the sealing reliability is not strong during long-term operation. Therefore, there is an urgent need for a test bench that can detect the performance of the globe valve.

Utility model content

The technical problem to be solved by the utility model is to provide a shut-off valve test bench for a low-temperature heat-insulating gas cylinder, which can detect the performance of the shut-off valve.

The technical solution adopted by the utility model to solve the technical problems is: provide a low-temperature insulation gas cylinder shut-off valve test bench, including a liquid nitrogen box, a temperature control box, a helium cylinder and a Dewar cylinder, and the helium cylinder is sequentially Connect to the measured station in the liquid nitrogen tank through a filter, a pressure reducing valve, a solenoid valve, a first shut-off valve, and a first pressure sensor; the Dewar bottle is connected to the liquid nitrogen tank through a second shut-off valve; The Dewar bottle is also connected to the measured station in the temperature control box through the first solenoid valve and the second pressure sensor, and the measured station in the temperature control box is also connected to the second station through the second solenoid valve. connected to the pressure sensor.

A torque wrench is installed on the measured station in the liquid nitrogen tank and the measured station in the temperature control box. The torque wrench is connected to the torque sensor through a universal coupling, and the torque sensor is connected to the torque sensor through a coupling. The reducer is connected with the reducer, and the reducer is connected with the servo motor.

A temperature sensor is also provided in the liquid nitrogen tank.

There is also a calibration gas cylinder between the first pressure sensor and the measured workpiece in the liquid nitrogen tank, and the calibration gas cylinder is connected between the first pressure sensor and the liquid nitrogen tank through a calibration cut-off valve. On the pipeline between the measured workpieces in the nitrogen box.

The air inlet of the Dewar bottle is connected with the air inlet through an air inlet valve and a pressure reducing valve in sequence.

Beneficial effect

Due to the adoption of the above-mentioned technical scheme, the utility model has the following advantages and positive effects compared with the prior art: the utility model realizes the shut-off valve through the liquid nitrogen tank, the temperature control box, the helium cylinder and the high-pressure liquid helium cylinder The low-temperature opening and closing test, low-temperature air-tightness test and low-temperature durability test can complete three different tests through one test bench, and the implementation methods are flexible and changeable.

Description of drawings

Fig. 1 is the system schematic diagram of the utility model.

Detailed ways

Below in conjunction with specific embodiment, further set forth the utility model. It should be understood that these embodiments are only used to illustrate the present utility model and are not intended to limit the scope of the present utility model. In addition, it should be understood that after reading the content taught by the utility model, those skilled in the art can make various changes or modifications to the utility model, and these equivalent forms also fall within the scope defined by the appended claims of the application.

The embodiment of the present invention relates to a test bench for a shut-off valve for a cryogenic insulating gas cylinder, as shown in Fig. The bottle 3 is connected to the measured station in the liquid nitrogen tank 1 through the filter 5, the pressure reducing valve 6, the solenoid valve 7, the first shut-off valve 8, and the first pressure sensor 9 in sequence; the Dewar bottle 4 passes through the The second stop valve 10 is connected with the liquid nitrogen tank 1; the Dewar bottle 4 is also connected with the measured station in the temperature control box 2 through the first electromagnetic valve 11 and the second pressure sensor 12, and the temperature control box 2 The station to be measured inside is also connected with the second pressure sensor 12 through the second solenoid valve 13 .

A torque wrench is installed on the measured station in the liquid nitrogen tank 1 and the measured station in the temperature control box 2, and the torque wrench is connected with a torque sensor 21 through a universal coupling 20, and the torque The sensor 21 is connected with a reducer 23 through a coupling 22 , and the reducer 23 is connected with a servo motor 24 . The servo motor can be controlled by PLC, and PLC control is a mature technology in this field. This case does not improve the control method, so it will not be repeated here.

The liquid nitrogen tank 1 is also provided with a temperature sensor 14, and the temperature sensor 14 can be a thermocouple to collect the temperature in the liquid nitrogen tank.

A calibration gas cylinder 15 is also provided between the first pressure sensor 9 and the workpiece under test in the liquid nitrogen tank 1, and the calibration gas cylinder 15 is connected to the first pressure via a calibration shut-off valve 16. On the pipeline between the sensor 9 and the measured workpiece in the liquid nitrogen tank 1 .

The air inlet of the Dewar bottle 4 is connected to the air supply port 19 through the air intake valve 17 and the decompression valve 18 in turn, and the air supply port 19 can be used to supply air to the Dewar bottle in real time.

The utility model can carry out low-temperature opening and closing test. When performing the low-temperature opening and closing test, first connect the liquid nitrogen outlet and helium high-pressure outlet to the test workpiece and the liquid nitrogen tank, adjust the position of the temperature sensor on the liquid nitrogen tank; open the liquid inlet and outlet valves on the Dewar bottle, and open the The liquid nitrogen is output to the liquid nitrogen tank, and the liquid nitrogen in the Dewar bottle starts to inject liquid nitrogen into the liquid nitrogen tank. When the temperature on the temperature sensor on the liquid nitrogen tank is observed to reach -196 degrees, close the measured stop valve. Rotate the torque wrench of the tested station by the servo motor, observe the torque value on the torque wrench, open and close 5 times in the full stroke, keep the pressure for 1Min, record the torque value three times, and complete the low temperature opening and closing test.

After the low temperature opening and closing test is completed, the low temperature air tightness test can be carried out. During the low temperature air tightness test, the helium gas cylinder is used to inflate and pressurize the low temperature shut-off valve immersed in the liquid nitrogen tank. When the pressure reaches the set pressure, the solenoid valve stops working, and the helium is leak tested The instrument is inserted into the liquid nitrogen tank to measure the leakage rate of helium, so as to complete the low temperature air tightness test.

The utility model can also carry out low-temperature durability test. When carrying out the low temperature durability test, when the temperature in the temperature control box reaches the set temperature, the cryogenic liquid nitrogen in the Dewar bottle fills and pressurizes the shut-off valve in the temperature control box through the first solenoid valve. After the pressure sensor detects the set pressure, the system starts the servo motor to drive the reducer to drive the manual operation part of the cut-off valve to work, and the torque sensor transmits the detected torque to the PLC. When the manual operation part of the low-temperature cut-off valve rotates in place, the PLC sends The signal reverses the manual operation part of the low-temperature globe valve, and the torque sensor transmits the detected torque to the PLC. When the durability times reach the set times, the system automatically stops to complete the low-temperature durability test.

Claims (5)

1. a cryogenic insulated cylinder stop valve testing table, comprise liquid nitrogen case (1), temperature control box (2), helium tank (3) and Dewar flask (4), it is characterized in that, described helium tank (3) is connected with the tested station in described liquid nitrogen case (1) by filtrator (5), reduction valve (6), solenoid valve (7), the first stop valve (8), the first pressure transducer (9) successively; Described Dewar flask (3) is connected with liquid nitrogen case (1) by the second stop valve (10); Described Dewar flask (3) is also connected with the tested station in temperature control box (2) with the second pressure transducer (12) by the first solenoid valve (11), and the tested station in described temperature control box (2) is also connected with described the second pressure transducer (12) by the second solenoid valve (13).

2. cryogenic insulated cylinder according to claim 1 stop valve testing table, it is characterized in that, on tested station in tested station and temperature control box (2) in described liquid nitrogen case (1), torque spanner is all installed, described torque spanner is connected with torque sensor (21) by Hooks coupling universal coupling (20), described torque sensor (21) is connected with speed reduction unit (23) by shaft coupling (22), and described speed reduction unit (23) is connected with servomotor (24).

3. cryogenic insulated cylinder according to claim 1 stop valve testing table, is characterized in that, is also provided with temperature sensor (14) in described liquid nitrogen case (1).

4. cryogenic insulated cylinder according to claim 1 stop valve testing table, it is characterized in that, between measured workpiece in described the first pressure transducer (9) and described liquid nitrogen case (1), be also provided with verification gas cylinder (15), described verification gas cylinder (15) is connected on the pipeline between the measured workpiece in described the first pressure transducer (9) and described liquid nitrogen case (1) by verification stop valve (16).

5. cryogenic insulated cylinder according to claim 1 stop valve testing table, is characterized in that, the air intake opening of described Dewar flask (4) is connected with gas supplementing opening (19) with reduction valve (18) by gas admittance valve (17) successively.