Abstract: An expandable centralizer is disclosed having a body having a first portion of circular cross-section and a second portion of polyhedral cross-section. Centralizing members are arranged on the faces of the second portion which, in a first position, limit the diameter of the tool so that it can pass through small openings in a wellbore. The centralizing members can then be moved hydraulically across the faces to extend and provide support for the expandable downhole tool in larger openings within the wellbore.

Abstract: An expandable centralizer is disclosed having a body having a first portion of circular cross-section and a second portion of polyhedral cross-section. Centralizing members are arranged on the faces of the second portion which, in a first position, limit the diameter of the tool so that it can pass through small openings in a wellbore. The centralizing members can then be moved hydraulically across the faces to extend and provide support for the expandable downhole tool in larger openings within the wellbore.

Abstract: Disclosed are an expandable well bore reamer and method utilizing a pair of reaming blades pivotally mounted on a central support member, each blade having an inner and an outer mounting arm positioned on opposite sides of such central support member with a movable cam with cam members to push against the inner mounting arm of each blade to pivot the reaming blades outward to an open position.

Abstract: An impact tool for use in a well bore. The impact tool provides a hammer action through reciprocal movement of a cam within a spring mechanism. In an embodiment a drill bit is included to provide an impact drilling tool which requires minimum weight on bit to operate. The impact tool can therefore be run on coiled tubing and wireline.

Abstract: A downhole reaming tool is disclosed having radially extendible cutting blades extended by hydraulic pressure directed into the tool to force an inner tubular body having protrusions thereon with tapered sides forward against the walls of mating recesses defined in such radially extendible cutting blades to extend the blades.

Abstract: A down-hole tool hydraulic force intensifier is disclosed utilizing an intensifier piston having an enlarged fluid facing top surface for receipt of hydraulic pressure thereon to force such intensifier piston against the activating structure of the down-hole tool to effectively increase the hydraulic force thereon.

Abstract: Disclosed are an expandable well bore reamer and method utilizing a pair of reaming blades pivotally mounted on a central support member, each blade having an inner and an outer mounting arm positioned on opposite sides of such central support member with a movable cam with cam members to push against the inner mounting arm of each blade to pivot the reaming blades outward to an open position.

Abstract: A wire line operated shut-in tool for a tubing string of an oil or gas well has a locking mandrel for cooperation with a ported landing nipple disposed below a packer in the tubing string to lock the tool in position, and a mandrel core which passes through the locking mandrel and is axially movable relative thereto, the core having a lower portion which is surrounded by the locking mandrel and is caused to rotate by the engagement of pins projecting inwardly from the locking mandrel with a jay slot assembly machined on the outer surface of the core when the core is moved axially. The arrangement of the jay slot assembly is such that by operating the wire line to move the core axially relative to the locking mandrel, the tool can be cycled between respective positions in which the well can be flowed, the reservoir shut-in, or the tool run out of the well.

Abstract: A pressure or temperature gauge includes a Bourdon tube which is coupled via a shaft to transmit rotation to a stylus carried by the shaft which makes a record on a cylindrical chart which moves axially of the shaft at a constant rate. The shaft is divided into two sections which are joined together by a flexible coupling; the upper section of the shaft is mounted for angular displacement about its longitudinal axis by the thrust bearing. One section has an integrally formed axial extension which is received in a recess in the facing end portion of the other shaft section. This construction of the stylus shaft allows the angular motion produced by the coiling and uncoiling of the Bourdon type generally through an angle less than 360.degree. to be faithfully transmitted without any axial motion of the shaft which would give rise to erroneous recording of pressure or temperature readings in relation to time.

Abstract: A centralizing device for use down-well in maintaining a sensor or other operational tool in a location accurately centralized on the axis of the bore-hole irrespective of the angular orientation of the device and associated tool at any given location. The device includes an elongate member carrying at angularly spaced locations three two pairs of opposed, two-arm linkages, each arm of each linkage being pivoted to the other arm of that linkage at a location spaced from the elongate member when in an extended position and being pivoted at the other end of the arm to a respective one of two slide blocks each of which is movable axially of the elongate member.

Abstract: A centralizing device for use down-well in maintaining an operational tool in a location accurately centralized in relation to the axis of the bore-hole irrespective of the angular orientation of the device and associated tool. The device comprises a shaft and at least three two-armed linkages angularly biased at their common axes towards the wall of the bore-hole by arrays of springs acting through slide blocks on the shaft. Axial movement of the blocks is limited by a central collar secured to the shaft.

Abstract: A rubber seal includes a bush (10) of natural rubber and end cups (12) each incorporating a multiplicity of synthetic fabric layers. The end cups (12) are rubberized and are fully integrally moulded into the main portion of the bush so that the final hollow cylindrical member has plane end faces and a smooth cylindrical peripheral surface a part of which is defined by an outer one of the layers of fabric.

Abstract: A method of testing for leaks in tubing and tube joints comprises placing within the tube to be tested a tool having spaced seals so that the seals are arranged on opposite sides of the joint to be tested in engagement at a constant pressure against the internal surface of the tubing. A search fluid such as 1 to 2% helium in air is passed through the tool under pressure and then out from the tool into the annular space between the outside surface of the tool and the inside surface of the tubing between the two seals. The presence of any helium is detected by means of a helium detector for example a mass spectrometer which has a probe extending to a gas trap surrounding the joint to be tested.