Gate valve core structure and classification-Yantai Valtone Valve Co., Ltd.

Gate valve core structure and classification

Jun 06,2022

Gate valve is a common cut-off valve, through the gate along the valve seat axis vertical direction to control the pipeline medium on and off, with low fluid resistance, simple structure, easy maintenance and so on. The following is a detailed introduction from the working principle, structural characteristics, application scenarios, installation precautions and so on:
First, the principle of work
Opening process:
Turn the handwheel or drive device, drive the valve stem to lift, the gate moves upward along the seat guide, away from the seat sealing surface, the medium through the valve body cavity circulation.
Closing process:
Reverse rotation of the handwheel, the valve stem drives the gate downward movement, until the gate and the valve seat close fit, the formation of a sealing surface, blocking the flow of media.
Second, the core structure and classification
1. Main structural components
Gate: divided into rigid gate (integral) and elastic gate (micro-deformation, to adapt to the sealing surface wear), is to achieve the key components of the cut-off.
Valve seat: with the gate to form a sealing surface, the material is often stainless steel, hard alloy or rubber (soft seal).
Valve stem: transfer opening and closing torque, divided into open stem (exposed, can judge the opening and closing status through the height of the stem) and dark stem (hidden in the valve body, suitable for space-constrained scenes).
Driving device: manual (handwheel), electric, pneumatic, hydraulic, etc., according to the working conditions to choose.
Third, the application areas and scenes
Industrial piping system:
Petrochemical industry: used for crude oil, refined oil, chemical raw materials pipeline cut-off, such as reactor import and export, storage tank cut-off valve.
Power industry: steam pipeline, boiler water supply system, control of high-temperature and high-pressure steam on and off (often using wedge gate valve).
Urban water supply and drainage and heating:
Waterworks, sewage treatment plant trunk pipelines, as the trunk cut-off valve; centralised heat supply network branch control.
Natural gas and gas system:
Natural gas long-distance pipeline, urban gas pipeline network cut-off, often using a fully welded structure of the parallel gate valve (good sealing, corrosion resistance).
Special working conditions:
Low-temperature environment (such as liquefied natural gas LNG pipeline): the use of low-temperature steel gate valve to prevent low-temperature brittle crack.
High viscosity media (such as heavy oil, molasses): the use of large calibre, smooth flow channel gate valve, reduce resistance.