Abstract: A casing patch assembly may include a patch seal having two ring-type seals with different performance characteristics. A first ring seals against a casing patch and a casing stub. A second ring self-adjusts to the size of the casing stub and is located so that it blocks the first seal, which may be softer material than the second ring, from being squeezed into an annular gap between the casing patch and the casing stub. The second ring may include a split feature to allow for the self-adjustment. Optionally, a third ring made of a malleable material may be located between the first and second rings to protect the first ring from being damaged by movement of the split feature.

Abstract: A hydraulic well jar accelerator used in a fishing string in conjunction with a well jar. The well jar accelerator includes inner and outer cylindrical assemblies movable longitudinally relative to each other and having an annular space between the cylindrical assemblies. An annular seal and an expansion sleeve disposed between the cylindrical assemblies are longitudinally spaced relative one another to form an annular liquid chamber in the annular space. The annular liquid chamber confines a hydraulic operating fluid. The volume of the annular liquid chamber can be adjusted by spring-loading the expansion sleeve without relative longitudinal movement of the inner and outer assemblies. The annular liquid chamber is operatively segregated into a main liquid chamber and an expansion liquid chamber. An annular seal body and an annular piston are disposed between the cylindrical assemblies in the annular liquid chamber. The seal body is attached to one of the cylindrical assemblies and has a first end surface.

Abstract: An apparatus for engaging a tubular member with a tension type spear in which the spear is locked to the tubular member so that it is not released when compressive or other non-tension loads are applied to it. The present invention locks the spear to the tubular member through abutment of a transfer assembly connected to the spear supporting mandrel after the spear has been set within the tubular member. The abutment of the transfer assembly and the tubular member lock the spear within the tubular member under tension so that compressive or other non-tension loads on the supporting pipe string will not affect the grip of the spear.

Abstract: A shock absorber assembly adapted to be used with a drill string dampening intermittent shocks and vibrational forces encountered with a drill string, the shock absorber assembly including a mandrel, a tubular body reciprocally mounted with respect to the mandrel, and a dampening device including an annular chamber adapted to be filled with a compressible fluid and a flexible wall with the mandrel adjacent the annular chamber for permitting flexure of the mandrel as needed for dampening.

Abstract: A shock absorber assembly for absorbing shocks encountered by a drill string wherein the shock absorber assembly is for use with a drill string having a working fluid therein and includes a body member affixed to the drill string, a mandrel mounted for reciprocal longitudinal movement with respect to the body member and a fluid dampening member floated within the central bore of the body member in engagement with the body member and the mandrel for absorbing shocks transmitted between the body member and the mandrel.