Performance failure testing device and method for low-temperature valve for LNG

A technology for failure testing and valves, which is applied in mechanical valve testing and other directions, and can solve problems such as sealing and locking failures

Pending Publication Date: 2020-09-15
NORTH CHINA MUNICIPAL ENG DESIGN & RES INST
0 Cites 0 Cited by

AI-Extracted Technical Summary

Problems solved by technology

[0004] In order to solve the technical problem of sealing and locking failure caused by the difference between the test and the actual working conditions in the existing external cooling method, the present invention provides a performance failure test device for low temperature valves for LNG. Under the operating frequency and gas operating conditions, base...
View more

Abstract

A performance failure testing device for a low-temperature valve for LNG comprises a medium gas source supply system, a closed box and a low-temperature valve testing station. The low-temperature valve testing station is positioned in the closed box; and the low-temperature valve testing station is provided with a driving mechanism and a to-be-tested low-temperature valve connected with the driving mechanism. A nitrogen concentration sensor, a temperature sensor and a gas outlet pipe are mounted on the side wall of the closed box. The medium gas source supply system comprises a raw material storage tank, a raw material gas supply main pipe and a plurality of branch distribution pipes, wherein an inlet of the raw material gas supply main pipe is connected with the raw material storage tank,a manual valve is installed on the raw material gas supply main pipe, an outlet of the raw material gas supply main pipe is connected with the branch distribution pipes, a valve and an electromagnetic valve are installed on each branch distribution pipe, and an outlet of each electromagnetic valve is connected with the to-be-tested low-temperature valve through a gas inlet pipe. According to themethod, the application performance of the low-temperature valve for LNG under the premise of normal work can be ensured to be measured and quantitatively evaluated, the test process is safe and reliable, the front and back test sequences are reasonably connected, the test time is short, and test media can be saved.

Application Domain

Machine valve testing

Technology Topic

Tested timeProcess engineering +9

Image

  • Performance failure testing device and method for low-temperature valve for LNG
  • Performance failure testing device and method for low-temperature valve for LNG

Examples

  • Experimental program(1)

Example Embodiment

[0026] See figure 1 , 2 , A performance failure test device for cryogenic valves for LNG, including a medium gas supply system, a closed box and a cryogenic valve test station.
[0027] The cryogenic valve test station is located in a closed box, and a drive mechanism and the cryogenic valve to be tested connected to the cryogenic valve test station are installed. The drive mechanism is composed of a torque and displacement sensor and a servo motor connected to it. No less than three sets of nitrogen concentration sensors and temperature sensors are installed on the upper, middle and bottom of one side wall of the enclosed box, and an air outlet pipe is installed on the other side wall.
[0028] The medium gas source supply system includes a liquid nitrogen storage tank, a liquid nitrogen supply main pipe and a multi-branch distribution pipe, wherein the inlet of the liquid nitrogen supply main pipe is connected to the liquid nitrogen storage tank and a manual valve is installed on it, The outlet of the liquid nitrogen supply main pipe is connected to a multi-branch distribution pipe, each branch distribution pipe is equipped with a valve and a solenoid valve, and the outlet of the solenoid valve is connected to the cryogenic valve to be tested through an air inlet pipe. The raw material gas supply main pipe and the multi-branch distribution pipe are pipes composed of metal pipes with a diameter of less than or equal to 200 mm. The inlet pipe connected to the outlet of the solenoid valve is a pipe composed of a metal pipe with a diameter of ≤150 mm.
[0029] The solenoid valve on each branch distribution pipe, the nitrogen concentration sensor and temperature sensor on the closed box, and the drive mechanism on the cryogenic valve test station are all connected to the control host PLC through a data/signal transmission line, and the solenoid valve passes the data / The signal transmission line is connected with the control host PLC to control the opening and closing time of the solenoid valve, and achieve the purpose of controlling the flow and working time of the supply medium.
[0030] The above-mentioned test method for the performance failure test device of the cryogenic valve for LNG includes the following steps:
[0031] ①Install the cryogenic valve to be tested, the nitrogen concentration sensor and the temperature sensor: place one or more cryogenic valves to be tested on the cryogenic valve test station, put the test position of the cryogenic valve in the closed box, and place the cryogenic valve to be tested The air inlet is connected to the corresponding LNG gas supply pipe, the air outlet is connected to the corresponding outlet pipe on the side wall of the closed box, and a nitrogen concentration sensor and a temperature sensor are installed on the upper, middle and lower parts of one side wall of the closed box respectively;
[0032] ②Start the medium gas source gas supply system to supply the internal medium liquid nitrogen to the cryogenic valve to be tested to simulate the actual operating state;
[0033] ③Initial temperature change and corresponding time test: At the beginning of the test, first turn on the solenoid valve, observe the release of liquid nitrogen in the closed box, and correspond with the outer surface temperature of the closed box collected by the temperature sensor and transmitted to the control host PLC to obtain a The series of temperature sensors collect the temperature and time changes of the points, and determine the time when the external temperature of the cryogenic valve under test is stable under the state of maximum flow, nominal flow and 5-30% of the nominal flow;
[0034] ④ Carry out the maximum flow performance, air tightness and torque change test:
[0035] According to the corresponding relationship between flow, temperature and time obtained in step ③, the maximum flow Q 1 As an example, determine the corresponding solenoid valve opening time t 1 , And use this as the operating time for cyclic testing. First, set the solenoid valve opening time to t through the control host PLC 1 , Working frequency n 1 , Initial torque performance k 11 , Initial nitrogen concentration k 12 , When the opening time reaches the utilization t 1 After that, the control host PLC closes the solenoid valve, the drive mechanism in the low-temperature valve test station moves, executes the valve opening and closing actions, records the operating frequency once, torque performance, and calculates and analyzes the arithmetic average of the 3 groups of nitrogen concentrations. Repeat the above steps, when the working frequency is n 1 If it reaches 10,000 times or the performance of stress and torque changes by 10% or the nitrogen concentration changes by 5%, the test ends;
[0036] ⑤Test the working performance, air tightness and torque change of the nominal flow:
[0037] According to the corresponding relationship between flow, temperature and time obtained in step ③, use the nominal flow Q 2 As an example, determine the corresponding solenoid valve opening time t 2 , And use this as the operating time for cyclic testing. First, set the solenoid valve opening time to t through the control host PLC 2 , Working frequency n 2 , Initial torque performance k 21 , Initial nitrogen concentration k 22 , When the opening time reaches the utilization t 1 After that, the control host PLC closes the solenoid valve, the drive mechanism in the low-temperature valve test station moves, executes the valve opening and closing actions, records the operating frequency once, torque performance, and calculates and analyzes the arithmetic average of the 3 groups of nitrogen concentrations. Repeat the above steps, when the working frequency is n 2 If it reaches 10,000 times or the performance of stress and torque changes by 10% or the nitrogen concentration changes by 5%, the test ends;
[0038] ⑥Test performance, air tightness and torque change at 20% of the nominal flow rate:
[0039] According to the corresponding relationship between flow, temperature and time obtained in step ③, use 20% of nominal flow Q 3 As an example, determine the corresponding solenoid valve opening time t 3 , And use this as the operating time for cyclic testing. First, set the solenoid valve opening time to t through the control host PLC 3 , Working frequency n 3 , Initial torque performance k 31 , Initial nitrogen concentration k 32 , When the opening time reaches the utilization t 3 After that, the control host PLC closes the solenoid valve, the drive mechanism in the low-temperature valve test station moves, executes the valve opening and closing actions, records the operating frequency once, torque performance, and calculates and analyzes the arithmetic average of the 3 groups of nitrogen concentrations. Repeat the above steps, when the working frequency is n 3 If it reaches 10,000 times or the performance of stress and torque changes by 10% or the nitrogen concentration changes by 5%, the test ends;
[0040] ⑦Get quantified adaptability and its performance change curve:
[0041] Taking the number of operations under the air-tight performance condition as the probability density, the life reliability of the cryogenic valve is evaluated, and the curve of different flow and torque changes is established to comprehensively evaluate the performance failure trend of the cryogenic valve.
[0042] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, and substitutions can be made to these embodiments without departing from the principle and spirit of the present invention. And variations, the scope of the present invention is defined by the appended claims and their equivalents.

PUM

PropertyMeasurementUnit
Diameter<= 200.0mm
Diameter<= 150.0mm

Description & Claims & Application Information

We can also present the details of the Description, Claims and Application information to help users get a comprehensive understanding of the technical details of the patent, such as background art, summary of invention, brief description of drawings, description of embodiments, and other original content. On the other hand, users can also determine the specific scope of protection of the technology through the list of claims; as well as understand the changes in the life cycle of the technology with the presentation of the patent timeline. Login to view more.
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products