Abstract: An improved head protection helmet assembly includes a helmet and a torso subassembly that is either a support vest or a shoulder pad subassembly. The helmet and torso subassembly are attached together in a way the helmet cannot move relative to the torso subassembly. A force applied to the helmet is transferred to the torso subassembly. The head of a person using the head protection helmet assembly can be moved inside, and relative to, the helmet. The head protection helmet assembly can also include front and rear body plates attached to the torso subassembly to reduce movement of the torso subassembly and the helmet.

Abstract: A through tubing bridge plug is disclosed. In the preferred and illustrated embodiment, a central hollow tube having a passage therein supports the external parts. The central passage terminates top and bottom with openings or passages. At the top end, a sleeve valve mechanism originally pinned in an open position is installed. When the installation is completed, the sleeve valve is closed by a sequence of operations to permanently close the flow path. The device is set and anchored by applying a relative downward force to an external sleeve thereby deploying multiple link toggle means to lock the device in location, additionally deploying a upwardly facing petal basket to receive a charge of sand and cement to form a plug, and also deploying a centralizer.

Abstract: The present disclosure is directed to a tracer fluid injector apparatus adapted to be lowered in a well borehole. In a sonde preferably equipped with a radioactive detector, a fluid injector system is disclosed. It utilizes an isolated cartridge of cylindrical construction having two closed ends. A piston in the cartridge moves to assure compression of a tracer fluid in the cartridge. It is installed or removed from the sonde at a specified cavity in the sonde. When placed therein, a bayonet stabs into the cartridge to open the cartridge for controlled flow of tracer fluid. The bayonet connects through appropriate check valves to a pump which delivers tracer fluid at a controlled metering means including an orifice on the exterior of the sonde so that radioactive tracer fluid is carefully handled by the present apparatus. A method of operation is also set forth.

Abstract: A freepoint indicator apparatus and technique are disclosed wherein a fluid tight hollow non-magnetic body member sized and adapted for passage through a well borehole is used. The apparatus houses a marking coil means for applying magnetic marks to the inside of stuck pipe or tubing string and dual longitudinally spaced Hall effect magnetic field sensing detectors. Magnetic marks are placed inside the stuck pipe. The pipe is then tensioned or torqued, or both, to strain it and the Hall effect devices are used to measure absolute and differential magnetic field strength before and after applying the strain to the pipe. Differences in these quantities are indicated at the location of the free point.