Abstract: A system for performing wellbore telemetry operations wherein a communication link between a subsurface location in a well and the location substantially at the surface is established and maintained through electromagnetic coupling between two insulated electric conductors. The first conductor is electrically coupled to a transmitter, normally located at the subsurface location, and extends upwardly in the well. The second conductor is electrically coupled to a receiver, normally at the surface location, and extends down into the well. Normally, the two conductors will overlap along a substantial portion of the lengths thereof. As the well is drilled deeper and the drill string is lengthened, the transmitter and the first conductor follow the progression of the wellbore into the earth, thereby reducing the overlap between the first and second conductors. When the two conductors cease to overlap, the second conductor may be lengthened to re-establish the overlap.

Abstract: A welding cable is described in which a welding current conductor, switch wires and a gas conductor tube are all contained in longitudinal passages in a single cable jacket. The passages containing the gas conductor tube and the switch wires are accessible through longitudinal openings in the jacket coextensive with the passages to facilitate insertion and removal of the switch wires and the gas conductor tube.

Abstract: Connecting device, which may be used for the spring member of a flexible hose, comprises a web having parallel sidewalls extending therefrom. Wire-receiving slot means extend inwardly from the free edges of the sidewalls and contact portion extends forwardly from the web so that when a wire spring in a flexible hose is inserted into the slot, the connecting device will extend from the end of the hose and parallel to the axis thereof. The wire-receiving slot means has features which make it particularly suitable for spring steel wires.

Abstract: A preinsulated pipe assembly and pipeline formed from a plurality of such assemblies. Each pipe assembly includes a pipe with a heater housing mounted thereon to form a cavity along the exterior of the pipe and a preformed insulation layer for insulating the pipe and the heater housing. A connecting assembly is used to join the pipe assemblies and form a pipeline. Pull means detachably connected to a heating element facilitates placement of the heating element in the heater housing cavities, and a pulling assembly attached to the heater element permits removal of the heater element after installation of the pipeline.

Abstract: The combination of a flexible, thin-walled plastic tube having thereon an external, electrically conductive, helical bead which is formed of a plastic mixed with a conductive material and which is heat sealed to the plastic of the tube. Electrical conductors are electrically connected to the bead adjacent the ends of the tube. The bead is normally opaque and the tube transparent. However, the tube may also contain a conductive material and be opaque.

Abstract: A suction pipe for a suction operated cleaner, especially a sectioned suction pipe, in which the pipe sections are provided with integral extensions thereon forming an axial channel along the outside of the pipe which is open on one side to receive a supply conduit, such as an electric cable.

Abstract: A cable system for wellbore telemetry includes a cable anchored at a subsurface location in a rotary drill string, guide assemblies for maintaining the cable in a looped configuration, and a cable gripping device for maintaining a portion of the cable in tension. Preferably the cable is provided with a novel releasable connector and latch assembly which (1) permits the cable to be electrically connected to a subsurface instrument and anchored to the drill string, (2) permits the cable to be maintained in tension, and (3) is releasable by manipulation of the cable at the surface.

Abstract: A conducting plastic pipe system comprising a male plastic pipe part and a female plastic pipe part with conducting covering layers which are interconnected by means of a conducting sealing ring between the male and female part. In case of outer covering layers on the pipe part the covering layer extends onto the inner side of the muff end of the female pipe part.

Abstract: A corrugated banding strap for securing an electrical cable to a tubing string for lowering into a well.

Abstract: The nozzle of an inert gas arc-welding gun is flexibly extended by coupling an elongate, tubular electrode between the body of the gun and its nozzle. The electrode is formed of spirally-wound conductive wire capable of being bent into any desired configuration needed for the particular job and of retaining its set disposition. A sleeve binds the wound wire electrode to maintain its circularity during bending and insulation is provided around the sleeve. Welding current is carried by the wire and the welding metal in wire form is passed through the bore of the wound wire. A steel spring coaxial with the electrode guides the welding wire. Inert gas is supplied through a passage provided between the insulation and the sleeve.