Abstract: A wellhead safety valve control system for opening and closing subsurface and surface safety valves in a predetermined sequence and certain components used with such control system. Dump valves in both latching and non-latching configurations are utilized within the control system. Embodiments of the dump valve may incorporate a time delay feature to ensure the subsurface safety valve is closed after a desired time period following the closure of the surface safety valve in the event of flowline anomalies. Provision is made for independent closure of the surface safety valve without closure of the subsurface safety valve.

Abstract: A wellhead safety valve control system for opening and closing subsurface and surface safety valves in a predetermined sequence and certain components used with such control system. Dump valves in both latching and non-latching configurations are utilised within the control system. Embodiments of the dump valve may incorporate a time delay feature to ensure the subsurface safety valve is closed after a desired time period following the closure of the surface safety valve in the event of flowline anomalies. Provision is made for independent closure of the surface safety valve without closure of the subsurface safety valve.

Abstract: Pump to supply fluid to at least two circuits in a control system for a production well. Each of the circuits is maintained at different pressures. The pump provides fluid to a plurality of poppets that are opened or closed depending on the positions of a cam surface which controls the position of the poppet. A pressure relief valve is used to prohibit fluid from entering a circuit unless the pressure exceeds the pressure of the fluid in the control circuit. The cam surfaces are controlled by a knob rotatable by an operator. By rotating the knob, the poppets can be opened or closed so as to provide fluid sequentially to each of the circuits and pressurize each circuit individually.

Abstract: An engine shutdown valve comprises a housing and a gate movable within a housing between a first position where the air flow through the shutdown valve is substantially unrestricted to a second position where the opening is restricted thereby stopping air flow. The gate is pivotable about an axis. The gate has an extension with a recess which is engageable by a piston movable between a first position where the gate is held in its latched position and a second position out of engagement with the recess so as to allow the gate to move to a position where the air passageway is closed. The gate is movable by a rod attached to the gate lever and which rod is biased by a compression spring mounted within a sleeve. The spring is adjustable to increase or decrease the force on the gate and such adjustment can be accomplished from outside the shutdown without disassembly of the entire valve.

Abstract: An actuator used to close and open a shut-in valve of a flowline. An indicator rod is threadedly connected to a connector which, in turn, is threadedly connected to the valve stem of the shut-in valve. A compression spring extends between a diaphragm plate and the bottom of the actuator. The shut-in valve is opened by pneumatic pressure above the diaphragm and the compression spring closes the shut-in valve by moving the valve stem when the pneumatic pressure above the diaphragm is exhausted to the atmosphere. The actuator including the compression spring may be disconnected from the bonnet on which the actuator is attached by rotating the indicator rod and removing the attachment bolts between the actuator and the attachment flange. The connector will be left on the valve stem.

Abstract: Dump/stop valve to regulate the time delay between the closure of a surface controlled subsurface safety valve and a surface controlled surface valve. Fluid is applied to a first cavity above a pilot plunger which maintains the subsurface safety valve in an open configuration. In the event the surface safety valve is intended to be closed, the fluid within the first cavity is bled off by a control circuit which immediately closes the surface safety valve. The pilot plunger responds by allowing the subsurface safety valve to be closed a predetermined and consistent time period thereafter.