Abstract: An improved shock absorbing snubber for derrick hooks is shown which includes a stationary hydraulic plunger and a telescoping barrel arrangement. A spring loaded check valve mounted on the plunger allows generally free fluid flow as the barrel is moved in one direction relative to the plunger but restricts the flow of fluid as the barrel is moved in the opposite direction.

Abstract: An improved slip-type elevator locking mechanism has a lock rod which has one end connected to the slip setting yoke and a free end extending generally parallel with the direction of movement of the slips in the elevator bowl. A cam arm mounted on the elevator at a central pivot point has a cam throat on one end which is adapted to receive the lock rod free end and an opposite end and is pivotable about the central pivot point between upper and lower lock rod engaging positions and a neutral, unlocked position. A fluid cylinder is pivotally mounted by a base end to the elevator and is pivotally attached at its output shaft to the cam arm opposite end for urging the cam arm to the neutral position. The fluid cylinder output shaft is spring-biased outwardly away from the base end in the absence of fluid pressure on the cylinder.

Abstract: A pneumatically operated rotary power slip assembly which is mountable in a rotary drilling table. It includes a stationary housing having an annular opening therethrough adapted for mounting generally coaxially with the pipe opening in the rotary table. The stationary housing has a conduit therein for transmitting pressurized fluid. The assembly includes a rotary housing having an annular opening therethrough, which housing is adapted for mounting generally coaxially with the opening in the rotary table and for rotation therewith. The stationary housing is provided with a pair of inflatable annular seals which, together with the rotary housing, form two axially spaced apart annular ducts between said housings upon inflation of the seals.