1- Purpose of using Gate Valve on stream
Gate Valve is used to open and close the flow only. Not commonly used in flow control with the following components.
2- Operation (open-closed) of Gate Valve
3- The Hydrostatic Test for Gate Valve requires 3 parts, Shell, Seat, and Backseat
The hydro-testing according to API 598. The valve standard is ASME B16.34
***Gate Valve – Hydrotest Backseat;
The Hydrostatic Backseat Test must be tested at a pressure of not less than 1.1 times the Maximum Operating Pressure by fully opening the valve and releasing the gland of the gate valve to check for leaks through the Backseat.
***Gate Valve – Hydrotest Shell;
Hydrostatic Shell Test must be tested at a pressure not less than 1.5 times the Maximum Operating Pressure by opening the valve partially open and tightening the gland to get the pressure. Then check for leaks through Shell.
***Gate Valve – Hydrotest Seat;
Hydrostatic Closure Test or Seat Test, continue to test from Shell Test at the pressure not less than 1.1 times of Maximum Operating Pressure by closing the valve fully closed and then checking the leak through Seat and Disk. Both tests must be done on two (2) – Side of Gate Valve.
***Valve – Pressure Test Duration;
Valve ‘s minimum hydrostatic/pneumatic pressure test, according to the table in API 598, where the test duration is the time we spend checking the valve leak after The pressure can be maintained at Test pressure.