What is a gate valve and how many types are there?

Gate Valve (gate valve) or gate valve is a cut-off valve (ISOLATING VALVE) by Gate Valve acts to cut liquids or various flowing substances inside the pipe or within the system, when wanting to open and close the water or liquid in the pipe line Disk or Gate valve valve (Gate Valve) acts to move down perpendicular to the direction of the fluid flow. There is a closed valve like a sliding door, shutting down the flow only. and move the valve valve back when wanting to open the way for the liquid to flow back through the pipe as before

How many types of gate valves are there?

If dividing valves by type of disc (DISK), there are 4 types.

  • Solid Taper Wedge Gate Valve
  • Flexible Wedge Gate Valve
  • Parallel Slide Gate Valve
  • Double Wedge Gate Valve

Solid Wedge Gate Valve

wedge-shaped The performance characteristics of this type of gate valve are flow does not flow flow through while fully open So it is full flow (full flow) has a back seat (when it is fully opened, it is the maximum packing, still not receiving pressure), strong

Flexible Wedge Gate Valve

The characteristics of this type of gate valve are Between the valve stem and the disc body is not continuous solid piece. But will allow the body to be loose or a little so that the Disc can move itself This allows for a tighter closure and also reduces friction or rubbing when opening.

Parallel Slide Gate Valve

The characteristic of this type of gate valve is that both disc and seat are parallel.

Double Wedge Gate Valve

It looks like 2 independent discs in the middle that come together by Ball Joint. Such characteristics make both discs better seal. When recording the final round, Ball Joint will force the disc to be separated from each other and each disc The body will seal independently on each seat side.

If the valve is divided by type The assembly of the valve body (BODY) with the BONNET can be divided into 5 types.

  • Screwed Bonnet
  • Bolted-Bonnet
  • Welded-Bonnet
  • Pressure-Seal Bonnet
  • Union Joint

Screwed Bonnet

Threaded design for easy assembly by machined male threads on both ends of the bonnet, threaded to female threads on one end forming the valve body. The other end is screwed onto the gasket fitting onto the valve stem.

Bolted Bonnet

It is the assembly of the valve body and bonnet with a flange, the contact surface is pressed with Bolts or Studs and Nuts, with a gasket inserted between the 2 flanges to prevent fluid leakage.

Welded Bonnet

Assembling the valve body and bonnet with a deadbolt between the two parts.

Pressure Seal Bonnet

Designed to allow the pressure inside the valve body and the bonnet to push the bonnet to the valve body above, with a seal ring acting as a seal between the valve body and bonnet while a thrust ring supporting the seal ring and There is a Spacer Ring to help another force to prevent Seal Ring from changing its shape as well as helping to support or support Studs & Nuts from losing the alignment perpendicularly.

Union Bonet

Design the assembly between the body and the bonnet similar to the union joint of the pipe system by using the union nut to lock and bonnet to compress with the male thread on the valve body.