Abstract: A torque shock absorber apparatus (39) comprised of a mandrel (2) and cylinder (8) with torque absorbing mechanism (8-12, 27) to absorb excessive torque while permitting the transmission of rotational energy to the drill string is connected in the drill string or as the drive mechanism in a jar or accelerator (40) to prevent excessive torque loading of the drill string.

Abstract: A rotary and longitudinal shock absorbing apparatus with an mandrel therein is connected to a drill string assembly to absorb abnormal longitudinal shocks and abnormal torsional shocks by cooperating hydraulic and mechanical means, while allowing communication of drilling fluid through the body of the apparatus. The construction of the apparatus is such that torque shock absorbing action is independent of the longitudinal shock absorbing action and the apparatus provides balanced internal and external pressure to permit its operation at all levels of hydraulic pressure.

Abstract: A jar apparatus (jar) 10 includes a plurality of pistons 16 that are secured together to form a piston assembly 23. Piston assembly 23 is movable axially in response to an actuating pressure differential between the jar bore 17 and the portion of borehole 19 that surrounds jar 10. Biasing spring 28 biases piston assembly 23 to return to a closed position when the actuating pressure differential is reduced by a predetermined amount. Piston assembly 23 forces a hammer member 32 and a movable anvil portion 30A axially to cock the jar in response to the applied actuating pressure differential. When the pressure differential is reduced, biasing spring 28 moves movable anvil portion 30A against anvil support portion 30B. Detent assembly 47 temporarily limits the velocity of hammer member 32 towards movable anvil portion 30A after the pressure differential is reduced. Compressed nitrogen 64 in nitrogen chamber 31 biases hammer member towards movable anvil portion 30A to deliver a jar impact.

Abstract: An energy accumulator for use with a well pipe string to enhance the jarring impact delivered to an object stuck in a well bore by an up and/or down jar mechanism includes inner and outer telescopically connected members relatively movable longitudinally to accumulate energy in a mechanical spring arrangement, gas or compressible liquid in the accumulator. Cooperating surfaces on the inner and outer members of the energy accumulator assure that the jarring impact of the jar mechanism members is delivered to the stuck independently of the tensile or compressive load applied to the object jar mechanism and independently of the load rate of accumulating energy in the energy accumulator.

Abstract: A sealing arrangement for the pin and box of a threaded connection between tubular members includes annular piston means for positioning in the box of one of the tubular members. Resilient seal means supported on the piston means seals between the pin end, box and piston means when the pin is threadedly engaged in the box. Additional seal means on the piston means is responsive to fluid pressure in the tubular members whereby the piston means may be urged toward sealing engagement with the pin end and the resilient seal means.

Abstract: An elongated mandrel has enlargements adjacent each end with a reduced diameter mandrel section extending therebetween. A stabilizer member is supported on the mandrel section by bearing surfaces for relative rotation of the mandrel with a well string when the stabilizer member engages a well bore wall. Spaced seals and wipers between the mandrel and stabilizer member form a closed reservoir for receiving lubricant, and a passage that communicates with the reservoir and the well bore has a floating piston therein responsive to well bore pressure to equalize the well bore and reservoir pressure without exposing the lubricant in the chamber to well bore contaminants.

Abstract: A telescopic shock absorber for use in a drill string includes a resilient arrangement to cushion telescopic contraction and extension of the shock absorber in response to shock loads and vibrations imparted during drilling. The shock absorber operates independently of the drilling fluid pressure conducted through the structure during drilling operations. A dampening system assists in cushioning the shock loads and vibrations and the dampening system and resilient arrangement are deactivated when jarring impacts are delivered to the well string by a drilling jar carried therein. The resilient arrangement provides a combination mechanical and hydraulic system for cushioning the impact loads and vibrations encountered.

Abstract: An energizer for use with a jar mechanism incorporated on inner and outer bodies in a well string to assist the jar mechanism in delivering an upward jar to the well string includes longitudinally spaced seal means between the inner and outer bodies forming a chamber for receiving a compressible medium therein. A differential area formed on one of the bodies within the compressible medium chamber compresses a compressible medium in the chamber as the well string is lowered to position the inner and outer bodies so that the jar mechanism is actuated to restrain relative longitudinal movement between the inner and outer bodies to an extended position whereby a pull force may be developed in the well string in one of the bodies.

Abstract: First and second separate one-way acting hydraulic jar sections each include inner and outer telescopically arranged tubular members with means for connecting one end of each the inner and outer tubular members of each jar section in the drill string. Spaced seal means between the inner and outer tubular members form a chamber in each jar section for confining hydraulic operating fluid.Hydraulic jar means are formed by cooperating means on the inner and outer tubular members within each operating fluid chamber. The cooperating means is spaced axially and disengaged in each fluid chamber when the drill string is in tension and compression during rotary drilling operation to inhibit damage and wear thereto. The hydraulic jar means in the first jar section is constructed to deliver an up jar and the jar means in the separate second jar section is constructed to deliver a down jar to the drill string.

Abstract: A double acting jar includes inner and outer telescopically arranged tubular parts movable longitudinally, but nonrotatable relative to each other. Cooperating means on the inner and outer telescopically arranged tubular parts deliver an upward jar to a stuck drill string upon relative longitudinal movement of the inner and outer telescopically arranged tubular parts in one direction and deliver a downward jar to a stuck drill string upon relative longitudinal movement of the inner and outer telescopically arranged tubular parts in the other direction. The cooperating means is constructed and arranged to be disengaged and maintained in an inoperative relationship when the drill string is in tension and compression during rotary drilling operations. When the jar is effected by a hydraulic jarring arrangement, fluid meter means incorporates a temperature responsive, compensating means to maintain substantially uniform flow rates through the metering means at varying temperature conditions.

Abstract: A double acting mechanical jar includes an outer housing and a mandrel extending longitudinally thereof with means connecting the mandrel and housing for relative longitudinal movement therebetween while inhibiting relative rotation therebetween.