Abstract: A flapper valve assembly for use in a flow conduit in a subterranean well, the assembly having a valve closure member pivotally connected to a floating hinge assembly that slidably engages a sleeve comprising the valve seat. A strut assembly comprising circumferentially spaced struts pivotally connected to the valve closure member away from the floating hinge member and pivotally connected to a spring guide surrounding the flow conduit is also provided, and is biased to force the valve closure member toward the closed position.

Abstract: A casing shut-in valve system (74) having a flapper valve assembly (34) and a shift head assembly (76); the flapper valve assembly (34) having an upper body member (36), lower body member (38), flow sleeve (40), valve seat sleeve member (42), flapper (54), flapper hinge assembly (56), and a plurality of spring strut assemblies (58) disposed on opposite sides of the flapper hinge assembly; the shift head assembly (76) having key housing (134) with bit sub (144) rotatably mounted in bearing (152), a plurality of outwardly biased shift keys (80), and a load equalizer plate (138) at each end of the key housing; the shift head assembly (76) being adapted to selectively open or close the valve by engaging and moving the flow sleeve (40) between defined upper and lower positions, thereby controlling the movement of flapper (54) through an angle (128) of rotation that is less than 90 degrees, and preferably about 45 degrees.

Abstract: A retrievable subsurface safety valve positioned in a well conduit is actuated to close by a predetermined flow rate through the safety valve. A valve member having a sealing surface is moveable by flow to sealingly engage an annular seat in the valve, closing the valve to flow. All forms of the invention safety valve have retrievable variable weight assemblies which releasably lock in the valve member for varying the flow rate at which each valve closes. In two invention forms, the weight assemblies when retrieved from the valve members leave the valve members open for passage of well tools through the valve members. In one invention form, the valve housing has a variable bias for biasing the valve member toward open position and this safety valve may be operated to expend the seat, housing and valve member with or without the variable weight assembly.

Abstract: A locking system utilizing metal seals for sealing and a rotary lock mandrel which is rotated to lock by a rotary running tool in a landing nipple in a well conduit. The lock mandrel has a metal sealing surface sealingly engageable with a metal seat in the landing nipple and orientors on a number of helically profiled segments which are rotatably engageable with mating profiled segments in the landing nipple. As the lock mandrel is lowered on the running tool into the landing nipple, lock mandrel segments are oriented between nipple segments, and the mandrel metal sealing surface engages the metal seat in the landing nipple. Downward jarring on the running tool rotates the mandrel segments into engagement with the landing nipple segments, locking the lock mandrel in the landing nipple, sealingly engaging the metal seal surface on the metal seat and releasing the running tool from the locking mandrel for retrieval from the well conduit.

Abstract: A safety valve for use in a well conduit which is automatically actuated to close when production flow impingement on a retrievable flow choke in the safety valve operating tube is sufficient. The safety valve utilizes all metal to metal seals and includes a unique roller detent mechanism, which releasably positions the operating tube in valve open position and provides snap closure of the valve. The operating tube has internal locking recesses and a metal seat. A flow choke of the size to cause safety valve closure at a selected flow rate is connected on a lock mandrel having a metal sealing surface. The lock mandrel with choke is lowered into the safety valve and operated to seal on the metal seat and lock in the locking recesses. When it is desirable to change the choke size, the lock mandrel is retrieved from the safety valve to surface.

Abstract: A locking system utilizing metal seals for sealing and a rotary lock mandrel which is rotated to lock by a rotary running tool in a landing nipple in a well conduit. The lock mandrel has a metal sealing surface sealingly engageable with a metal seat in the landing nipple and orientors on a number of helically profiled segments which are rotatably engageable with mating profiled segments in the landing nipple. As the lock mandrel is lowered on the running tool into the landing nipple, lock mandrel segments are oriented between nipple segments, and the mandrel metal sealing surface engages the metal seat in the landing nipple. Downward jarring on the running tool rotates the mandrel segments into engagement with the landing nipple segments, locking the lock mandrel in the landing nipple, sealingly engaging the metal seal surface on the metal seat and releasing the running tool from the locking mandrel for retrieval from the well conduit.

Abstract: A lock system for wells which includes a landing nipple in the well tubing and two embodiments of a lock mandrel, which are sealingly engageable and releasably lockable in the landing nipple to control flow through the well tubing. One lock mandrel is closed to flow and "plugs" the landing nipple. The other lock mandrel, which will operate as a standing valve, has a through flow passage and a check valve preventing downward flow through the flow passage and lock mandrel. Both lock mandrels utilize "C" rings for locking in landing nipples and may be released for expending downwardly from landing nipples by a predetermiend downward force.

Abstract: A sucker rod coupling comprising a body member and a plurality of axially and circumferentially spaced roller assemblies adapted to reduce friction and wear between the body member and the well tubing in which it is used, each roller assembly further comprising a plurality of rollers linked by a chain, each roller being adapted to rotate within the chain while the chain revolves around a roller guide connected to the body member.

Abstract: Methods of and apparatus for plugging a well below a rod pump to permit bleeding off the pressure thereabove so that the pump can be removed from the well for replacement or repairs and reinstalled for further pumping operations, the pump being connected to a valve mechanism in the well in a manner which permits the valve to be closed as a result of lifting the pump, this connection being releasable to permit the pump to be pulled free of the valve and withdrawn from the well after the well pressure has been bled from above the closed valve. When the pump is installed again, the pump automatically reconnects to the valve. This invention is particularly useful in wells which are stimulated by the injection of steam.

Abstract: A hydraulic well pump for operating a pump sucker rod string including a hydraulic cylinder assembly for raising and lowering the sucker rod string and a fluid counterbalancing system for offsetting the combined weight of the reciprocating service equipment, the fluid column above the pump plunger, and the sucker rod string. One counterbalancing embodiment includes an air supported piston on the movable cylinder exposed to an air chamber below the air piston functioning independently of the hydraulic and power and logic system of the pump. Another counterbalancing system embodiment uses a hydraulic fluid accumulator connected into the system fluid power and logic for supercharging the hydraulic power pumps during the lift stroke and providing opposing force during the downstroke.

Abstract: A hydraulic well pump for operating a pump sucker rod string including a hydraulic cylinder assembly for raising and lowering the sucker rod string and a fluid counterbalancing system for offsetting the combined weight of the reciprocating service equipment, the fluid column above the pump plunger, and the sucker rod string. One counterbalancing embodiment includes an air supported piston on the movable cylinder exposed to an air chamber below the air piston functioning independently of the hydraulic and power and logic system of the pump. Another counterbalancing system embodiment uses a hydraulic fluid accumulator connected into the system fluid power and logic for supercharging the hydraulic power pumps during the lift stroke and providing opposing force during the downstroke.

Abstract: A hydraulic power and control system for operating a reciprocating hydraulic mechanism including pump means connected to the hydraulic mechanism, a continuous torque hydraulic motor, a direction control driven by the motor to sequentially direct hydraulic power fluid to separate inlets of the mechanism, an escapement for restraining the motor at 180.degree. intervals of rotation for sequentially holding the direction control at two separate positions, one for supplying one inlet and the other for supplying the other inlet of the mechanism, and hydraulic limit valves for controlling the escapement when a reciprocating member of the mechanism reaches the end of each stroke. One embodiment has two constant volume hydraulic pumps connected with the hydraulic mechanism through a reversing valve assembly operated by a scotch yoke connected with the escapement.

Abstract: A hydraulic well pump for operating a pump sucker rod string including a hydraulic cylinder assembly for raising and lowering the sucker rod string and a fluid counterbalancing system for offsetting the combined weight of the reciprocating service equipment, the fluid column above the pump plunger, and the sucker rod string. One counterbalancing embodiment includes an air supported piston on the movable cylinder exposed to an air chamber below the air piston functioning independently of the hydraulic and power and logic system of the pump. Another counterbalancing system embodiment uses a hydraulic fluid accumulator connected into the system fluid power and logic for supercharging the hydraulic power pumps during the lift stroke and providing opposing force during the downstroke.

Abstract: The pump or pumps for supplying fluid to the two ends of a double-acting cylinder include a direction control, such as a direction control valve, shiftable between extend and retract conditions. A drive mechanism for the direction control includes a rotary hydraulic motor and a driven rotary drive mechanism for shifting the direction control. Hydraulic fluid is supplied to the drive motor through parallel connected start and stop valves. The start valve is opened in response to the movements of the hydraulic cylinder toward a stroke limit. The stop valve is operated in response to the shifting of the direction control, so that the motor is operated intermittently to reverse the direction control when the cylinder reaches the limit of an extend or retract stroke. The stop valve is controlled by the drive mechanism in timed relation with the shifting of the direction control. The start valve may be closed by that drive mechanism in timed relation with the opening of the stop valve.

Abstract: A diverter device for use in direction pumpdown or through the flowline (TFL) tools through a connector joining a main flowline to at least one branch flowline. The diverter member is pivoted by operation of a removable operator to allow movement of the tool string through a selected branch of the connector. A sealing system allows removal of the operator having to depressurize the flowlines joined at the connector. The manual operator can be easily padlocked in position. The hydraulic operator provides a rugged, reliable mechanism to translate linear movement of a hydraulic piston into rotary movement of the diverter.

Abstract: A diverter device for use in directing pumpdown or through the flowline (TFL) tools through a connector joining a main flowline to at least one branch flowline. The diverter member is pivoted by operation of a removable operator to allow movement of the tool string through a selected branch of the connector. A sealing system allows removal of the operator without having to depressurize the flowlines joined at the connector. The manual operator can be easily padlocked in position. The hydraulic operator provides a rugged, reliable mechanism to translate linear movement of a hydraulic piston into rotary movement of the diverter.