Function classification of instrument valves

Function classification of instrument valves
There are many functions of instrument valves. Different valves should be selected for different functions. Different types of valves have different structures. These functions are the means to effectively control the process and ensure safety. Valves are generally divided into automatic valve and drive valve, automatic valve (such as safety valve, pressure reducing valve, steam trap, check valve) depends on the change of device or pipeline medium pressure to achieve the purpose of opening and closing. Drive valve (gate valve, globe valve, ball valve, butterfly valve, etc.) is driven by the device (manual, electric, hydraulic, pneumatic, etc.) to regulate the pressure, flow and direction of the medium in the pipeline. Due to the different pressure, temperature, flow and physical and chemical properties of the medium, the control requirements and use requirements of the device and pipeline system are also different, so the functions of the valves are not the same.
According to the function of instrument valve:
Block valve: block valve, also known as closed-circuit valve, its role is to connect or cut off the medium in the pipeline. Block valves include gate valves, globe valves, plug valves, ball valves, butterfly valves and diaphragm valves.
Control valve: control valve includes control valve, throttle valve and pressure reducing valve, whose function is to regulate the medium pressure, flow and other parameters.
Check valve: check valve is also known as one-way valve or check valve, its role is to prevent the medium in the pipeline backflow. The bottom valve of pump suction valve also belongs to check valve.
Safety valve: the function of safety valve is to prevent the medium pressure in pipeline or device from exceeding the specified value, so as to achieve the purpose of safety protection.
Diverter valve: diverter valve includes all kinds of distribution valve and trap, which is used to distribute, separate or mix the medium in the pipeline.
Exhaust valve: the exhaust valve is an essential auxiliary component in the pipeline system, which is often installed at the commanding height or elbow to eliminate the excess gas in the pipeline, improve the efficiency of pipeline and reduce energy consumption.