An instrument valve is a type of pipeline accessory. It is a device used to alter the cross-sectional area of the passage and the direction of medium flow, controlling the flow of the conveyed medium.

Valves for instruments have the following applications:

1. Connect or disconnect the medium in the pipeline. Such as gate valves, stop valves, ball valves, plug valves, diaphragm valves, and butterfly valves, etc.

2. Adjust and control the flow and pressure of the medium in the pipeline. Such as throttle valves, regulating valves, pressure reducing valves, and safety valves, etc.

3. Alter the direction of medium flow in the pipeline. Such as distribution valves, three-way gate valves, three-way or four-way ball valves, etc.

4. Prevent backflow of media in pipelines. Such as various different structures of check valves, bottom valves, etc.

5. Separation Media. Such as various steam traps with different structures, air traps, etc.

6. Indicate and adjust liquid level. Such as liquid level indicators, liquid level regulators, etc.

7. Other Special-Purpose Items. Such as temperature control valves, emergency cut-off valves for overcurrent protection, etc.