【2025 VID】Video of the instrument valve assembly set
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This post was last edited by zhoudingshengs on 2025-5-6 08:58. The video is: Instrument valve assembly set.
Valve assemblies play an important role in industrial processes, with the 2-valve assembly, 3-valve assembly, and 5-valve assembly being the three most common types. They are primarily used for the connection and operation of pressure and differential pressure measuring instruments such as pressure transmitters and differential pressure transmitters; each valve assembly has specific functions, structures, and application scenarios.
A two-valve assembly consists of two separate valves, and is commonly used for the protection and drainage operations of pressure transmitters. •Isolation Valve: Used to isolate the pressure transmitter from the process pipeline; it can be closed to allow for the maintenance or replacement of the transmitter. •Vent Valve: Used to release the residual fluid inside the pressure transmitter, enabling operation or calibration under safe conditions.
Three-valve assembly: consists of two stop valves (high-pressure side and low-pressure side) and a balance valve.
Core functions of the three-valve assembly: (1) To connect or disconnect the positive and negative measurement chambers of the differential pressure transmitter from the pressure guiding tubes. (2) The balance valve is used to balance the pressures in the positive and negative pressure chambers, preventing the transmitter diaphragm from being damaged due to excessive pressure differences.
Operating characteristics of the three-valve assembly: During operation, it is necessary to follow the sequence of \"first open the high-pressure valve → then close the balance valve → finally open the low-pressure valve\", while the reverse sequence is used during shutdown.
Composition of the five-valve assembly: Two drain valves (or calibration valves) are added to the three-valve assembly, resulting in a total of five valves. The drain valve is used to discharge the residual medium (such as gas or liquid) or impurities in the pressure guide tube, thereby improving measurement accuracy. It supports online verification of the transmitter zero point without the need to remove the device.
Two-valve set: Used for pressure measurement, applicable in scenarios requiring single-point pressure monitoring, such as oil and gas transmission pipelines and boiler pressure control.