Abstract: The present invention provides a device and method for protecting, by means of a casing, a measuring instrument or a specialzied tool fixed to the end of a drill string. Said drill string has substantially at is end and before said tool a first guide member and said casing has a second guide member, said first and second guide member being adapted for cooperating together so as to allow movement of said casing relatively to said tool or instrument.

Abstract: A method and device are provided for carrying out measurements and/or operations in a well. The device comprises tubing of a diameter less than that of the well, at least one measurement or operation instrument as well as at least one sealing member surrounding said tubing, a base or probe support and a flexible connecting member comprising at least one electrical connection, said flexible connecting member connects the base to the measuring instrument.

Abstract: A method and device are provided for carrying out measurements and/or operations in a well. In this method at least one tube is used which includes at least two parts one of which is an upper tubular part and another of which is a lower tubular part, an extension having an upper end and a lower end and an instrument for carrying out measurements and/or operations fixed to the lower end of said extension. The method involves the steps of:(a) fitting said extension equipped with said instrument to the lower part of said tube,(b) fitting the upper part of the tube above the lower part of the tube thereby providing greater penetration into the well of the assembly formed by the lower tube, the extension and the instrument and(c) effecting movement of the extension and of the instrument with respect to the tube to a position of said instrument where the measurement and/or operations may be carried out.

Abstract: A side-entry connection for incorporation in pipe strings, such as a drill-pipe string, and for sealingly passing a cable from the inside to the outside of the pipe string is disclosed. The side-entry connection comprises a connection sub and a sleeve which is slidable inside the axial bore of the connection sub between a top position above said cable entry and a low position in which the sleeve closes said cable entry. Means are provided for retaining the sleeve in each of said positions, and the sleeve includes cutting means at its lower end for severing the cable when the sleeve is moved to its lower position. A retrievable plug is used to close the top of the sleeve and hydraulic pressure is applied to the plug from the surface so as to move the sleeve from its top position to its low position for closing the side entry and for severing the cable.

Abstract: A method for effecting logging or servicing operations in a predetermined zone of a well, following an initial portion thereof, comprising fastening a logging or servicing tool body at the end of a string of rods lowered into the well, said tool body being provided with an electric male connector, lowering at the end of an electric transmission cable, from the surface, a female connector adapted to fit the male connector, coupling said female and male connectors by the action of a force generated at least partly by the pressure of a fluid pumped through the string of rods, supplying electric power, through said transmission cable and said connectors, to said logging or servicing tool for its operation in said predetermined zone, and with rotating means located between the string of rods and said tool, rotating the tool without rotating the whole string of rods.

Abstract: A method for effecting logging or servicing operations in a predetermined inclined or horizontal zone of a well, following an initial vertical portion thereof, comprising fastening a logging or servicing tool body at the end of a string of rods lowered into the well, said tool body being provided with an electric male connector, lowering at the end of an electric transmission cable, from the surface, a female connector adapted to fit the male connector, coupling said female and male connectors by the action of a force generated at least partly by the pressure of a fluid pumped through the string of rods, and supplying electric power, through said transmission cable and said connectors, to said logging or servicing tool for its operation in said predetermined zone.