Abstract: A male connector, adapted to engage a female connector to form an electrical connection, has an electrically insulative body, an electrically conductive pin secured to the body and extending through a face of the body for electrical contact with the female connector, a cylindrical pin insulator formed in place about the pin and extending through the face of the body, and a wire seal formed in place about the wire jacket and arranged to seal between the wire and the body. In some embodiments, the pin insulator is disposed between two flanges of the pin. The described version has nine wires, pins and corresponding pin insulators. The body preferably defines a circumferential groove for retaining an o-ring seal, and is capable of withstanding a static differential pressure of 15,000 pounds per square inch across the o-ring seal without sustaining structural damage. The male connector is preferably constructed to pass through a circular opening of 1.00 inch diameter. Preferred materials are also disclosed.

Abstract: A female electrical connector adapted to be lowered down a well on an electrical cable for remote connection to a down hole male connector. The connector includes a housing with an attachment for securing the female electrical connector to the cable, a female electrical contact within the housing, and an insulator disposed between the housing and the female electrical contact. The female electrical contact is in electrical communication with the cable and includes a circumferential ring defining a central axis, and a cantilever finger extending generally axially from the ring. The finger has a first portion extending generally radially inward from the ring, and a second portion extending generally radially outward from the first portion to an axially-directed, distal end. The first and second portions of the finger define therebetween a radially innermost contact surface.

Abstract: A down hole tool, constructed to be suspended in a well by pipe, includes a housing, a circulation piston, a biasing member and a pressure-compensation system. The housing defines a flow chamber in open fluid communication with the pipe interior, a bypass port for fluid flow between the flow chamber and the well, a mud chamber in open communication with the well, and a sealed chamber separated from the flow chamber by a sealed interface. The circulation piston separates the flow and mud chambers and is arranged for movement between a first, bypass port-blocking position and a second, bypass port-exposing position in response to pressure in the flow chamber. The biasing member biases the circulation piston to its first position, and the pressure-compensation system limits the pressure difference between the flow and sealed chambers, thereby limiting the pressure difference across the sealed interface. The tool has particular application to tools, e.g.

Abstract: A bulkhead adaptor for use with a downhole tool to be pumped through a well casing or drill pipe on a cable. The bulkhead adaptor includes a housing assembly havingan upper attachment element for connecting the housing assembly to the cable, and a lower attachment element for connecting the housing to the tool. The adaptor also has a circular swab cup defining a surface area exposed to a flow of pumping fluid. The swab cup is removably attached to the housing and has an outer diameter enclosing a projected area greater than the projected area of the tool, measured in a plane transverse to said well casing or drill pipe. Various preferred materials and methods of use are disclosed. The invention can especially improve the pumping of tools down horizontal or highly deviated wells.