Gate valves are primarily meant to serve as isolation valves. In service, these valves generally can be fully open or fully closed. When fully open, the fluid or gas flows with the valve inside a straight line with almost no resistance. Gate valves such as dual wafer check valve mustn't be used in the regulation or throttling of flow because accurate control isn't likely. Furthermore, high-flow velocity in partially opened valves could cause erosion with the discs and seating surfaces. Vibration may also result in chattering on the partially opened valve disc. An exception on the above were created gate valves which are used for low-velocity throttling; as an example, guillotine gate valves for pulp stock.

There are four primary designs for gate valves – a slab gate, an expanding gate, a wedge valve and also a knife gate valve.

Slab gate valves are comprised of your single gate unit which raises and lowers between two seat rings and therefore are primarily employed for transporting crude oil and NGLs. The Cameron GROVE G4N fabricated gate valve and WKM Saf-T-Seal gate valve are great choices for this application.

Unlike a slab gate valve that just has one unit, an expanding gate valve includes two units – a gate and segment. The gate and segment units collapse against 1 another for travel, and separate in the event the valve is fully opened or fully closed, to affect a mechanical seal.

Damage Control: Gate valves are specifically advantageous when used to halt the flow of liquids when partial flow could otherwise cause irrevocable injury to pipe lines and systems. When the valve fully opens,  the gate just isn't exposed towards the flow of materials avoiding damage from strong currents of fabric. This avoids wear and tear on the gate from bending or closing off center from strong forces from everyday material flow transportation.

Wedge gate valves are comprised of the tapered gate that may be metal-to-metal sealing. In contrast to a slab gate valve or perhaps an expanding gate valve, wedge gate valves are certainly not piggable because with the void that's left in the bottom on the valve body if the valve is open. These valves do not possess a bore throughout the gate itself – instead, the gate retracts in to the valve body when open – which saves height space that is certainly necessary for slab and expanding gate valves.