Gate valves can be classified into many categories according to different classification standards, mainly including the following types:
Classification by structural characteristics:
Parallel gate valve: The gate and the valve seat sealing surface are parallel to each other, with a simple structure and good sealing performance, but the opening height is large, suitable for general working conditions.
Wedge gate valve: The gate and the valve seat sealing surface are at a certain angle (usually a wedge angle), with a self-locking function, a small opening height, suitable for high pressure, high temperature and large diameter occasions.
Rising stem gate valve: The valve stem nut is on the valve cover or bracket, and the valve stem rises and falls during opening and closing, which is convenient for operation and maintenance.
Non-rising stem gate valve: The valve stem nut is in the valve body and only rotates, suitable for occasions with limited installation space.
Classification by sealing method:
Soft sealing gate valve: The sealing surface is made of soft materials such as rubber and polytetrafluoroethylene, suitable for normal temperature, low pressure and corrosive media.
Hard-sealed gate valve: The sealing surface is made of hard materials such as metal, which is suitable for high temperature and high pressure occasions, but the sealing performance is slightly inferior to the soft-sealed gate valve.
Classification by driving method:
Manual gate valve: Open and close by manually rotating the handle or handwheel.
Electric gate valve: Driven by an electric motor, suitable for automatic control systems.
Pneumatic gate valve: Driven by a pneumatic device, suitable for occasions that require rapid opening and closing.
Hydraulic gate valve: Driven by a hydraulic device, suitable for occasions that require a large opening and closing force.
Classification by use:
Ordinary gate valve: Used to cut off fluid media.
Throttling gate valve: Has a certain throttling function and can be used to adjust the flow rate.
Insulated gate valve: Suitable for media that require insulation.
Cryogenic gate valve: Suitable for cryogenic media.
Classification by connection method:
Flange-connected gate valve: Connected to the pipeline through a flange, suitable for gate valves with larger diameters.
Threaded gate valve: connected to the pipe by thread, suitable for gate valves with smaller diameters.
Welded gate valve: connected to the pipe by welding, suitable for occasions requiring higher sealing performance.
These classification methods help us better understand the different characteristics and applicable scenarios of gate valves, so as to select the appropriate gate valve to meet specific needs.