Parallel Expanding Gate Valve
The parallel expanding gate valves acc. to the API Spec.6A requirements are used by the oil industry for neutral or sour fluids (oil, gases, water and drilling mud) and the following pressure classes: 2,000/3,000/5,000 and 10,000 psi (140/210/350 and 700 bar).
The most important component of the valve is its closing part, namely the gate, which consists of two elements: gate and segment attached by a spring. During the gate-to-seat sealing operation, the two inclined faces of the gate and segment slide one another. Rotating the hand wheel helps with transmitting the gate movements upward and downward by means of the operating stem.
The seats are pressed into the body; in case of those valves being used under neutral service conditions, a teflon ring pressed into each seat represents the seat-to-gate sealing element. In case of sour service conditions, the seat-to-gate sealing operation is made by a metal-to-metal touch ( for example, by hard facing using stellite 6 ). A back- or side-installed “O” ring may be used as an additional seal of the seats.
The materials to be utilized are in accordance with the requirements imposed by the service conditions of the valves. The materials to be used for corrosive service conditions meet the NACE MR0175 requirements.
Minimum informative data to be specified in the inquiry:
- valve type
- sizes and rated pressure
- end connection type and sizes
- temperature and service conditions
- PSLs and PRs
For more information, please consult the wellhead equipment brochure here.