Patent ID: 9677377
Date: 2017-06-13
CPC Classifications: E21B

Claim:
1. A control system for a Subsurface Safety Valve (SSSV), comprising: an actuating piston mounted in a housing with at least one seal and connected to the SSSV, the actuating piston having a first end and a second end, the first end in fluid communication with a control line; a primary pressure reservoir in fluid communication with the second end of the actuating piston, the reservoir configured to contain a fluid under pressure; an equalizing piston in fluid communication with both the control line and with the second end of the actuating piston, the equalizing piston remaining in a closed position during shifting of the actuating piston with pressure applied or removed from the control line, the equalizing piston movable to an open position upon a control system failure that reduces pressure in the primary reservoir to below a threshold value; and a condition sensing and chemical injection assembly in fluid communication with the primary reservoir and the second end of the actuating piston, wherein the closed position of the equalizing piston blocks fluid communication between the control line and the condition sensing and chemical injection assembly, and the open position of the equalizing piston permits fluid communication between the condition sensing and chemical injection assembly and the control line.