Opening & Closing Sequences

Well Opening Sequence for Well Control Panels

The well control panel contains a pneumatic interlock circuit to ensure the following well opening sequence.

• Hydraulic pressure applied to the subsurface safety valve (SCSSV).
• Pneumatic or hydraulic pressure applied to the master surface safety valve (MV).
• Pneumatic or hydraulic pressure applied to the wing surface safety valve (WV).

Well Closing Sequence for Well Control Panels

The well control panel contains an adjustable time delay to ensure the following well closing sequence.

• Pneumatic or hydraulic pressure vented from the wing surface safety valve (WV).
• Pneumatic or hydraulic pressure vented from the master surface safety valve (MV).
• Hydraulic pressure vented from the subsurface safety valve (SCSSV).