What is Gate valves
Gate valves are widely used for all types of applications and are suitable for both above-ground and underground installation. Not least for underground installations it is paramount to choose the right type of valve to avoid high replacement costs.
Gate valves are used to shut off the flow of liquids rather than for flow regulation. When fully open, the typical gate valve has no obstruction in the flow path, resulting in very low flow resistance. The size of the open flow path generally varies in a nonlinear manner as the gate is moved. This means that the flow rate does not change evenly with stem travel. Depending on the construction, a partially open gate can vibrate from the fluid flow
Gate valves are mostly used with larger pipe diameters (from 2″ to the largest pipelines) since they are less complex to construct than other types of valves in large sizes.
Main gate valve parts of a gate valve are: body, seat, gate, stem, bonnet and actuator. The main operation mechanism is very simple. When the handwheel is turned, it rotates the stem, which is translated into the vertical movement of a gate via threads.
There are three ways to classify the gate valve.
Types of Disk
Solid taper wedge
Flexible wedge
Split wedge or Parallel disks Valve
Types of Body Bonnet Joint
Screwed Bonnet
Bolted-Bonnet
Welded-Bonnet
Pressure-Seal Bonnet
Types of Stem movement
Rising Stem or OS & Y Type (Outside Stem and Screw Type)
Non-rising Stem type
Gate valvesare used in almost all fluid services such as air, fuel gas, feedwater, steam, lube oil, hydrocarbon, and all most any services.
Some special gate valve is used in slurry and powder product also such as knife gate valve
