A hydraulic valve operating circuit for providing positive opening and closing of a downhole safety valve includes shut-off valves which prevent leakage of fuel to the outside environment if a leak should occur in the hydraulic lines which are connected to the hydraulic actuator of the downhole safety valve. Safety Valves A hydraulic control line is connected to the actuator of the safety valve through a normally-closed shut-off valve and the hydraulic control line is also connected to the actuator of the shut-off valve to hold both the shut-off valve and the downhole safety valve open when the hydraulic line is pressurized. Globe Valves Another valve moves to a position to direct the flow of fluid from the safety valve to an accumulator when the pressure in the control line falls below a predetermined value to insure that the downhole safety valve will close properly. REDUCING VALVES The accumulator and the actuator control valves can be replaced by a single gate valve having a novel porting arrangement as shown in one embodiment of the present invention. The gate valve can be adapted for use with either a balanced or a nonbalanced downhole safety valve. A hydraulic valve for use with a source of pressurized hydraulic fluid and a downhole safety valve mounted in a petroleum well, said safety valve including a safety valve actuator having an inlet port, said hydraulic valve comprising: a valve base having first and second inlets and an outlet; means for connecting said base outlet to said safety valve inlet port; a fluid accumulator; a valve gate having first and second ports and a passageway therethrough; means for slidably mounting said valve gate in said valve base to connect said base outlet to said first base inlet through said first gate port and to connect said accumulator to said second base inlet through said second gate port when said valve gate is in a first position, said gate passageway interconnecting said accumulator and said gate outlet when said valve gate is in a second position; and valve actuator means for selectively moving said valve gate between said first and second positions.

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