Drexel Equipment (uk) Limited

Servwell Engineering Limited

Boc-nowsco Limited

Smith International, Inc.

Oiltools International B.v.

Renovus Limited

Eljay Well Services Limited

Drexel Equipment Limited

Drexel Oil Field Service (hk) Limited

Richard Alvin Armell

Ruairidh Andrew Cooper

Giancarlo Tomasso Pia

Bruce H McGarian

John G Misselbrook

David Coull

Andrew Scott

A downhole mixing tool and method for removing sand and other debris from a wellbore which combines the sand with a treatment fluid so that the sand is lifted to the surface of the well for removal. The tool includes a chamber into which the sand laden fluid is drawn and the treatment fluid is introduced. Ports into the chamber are arranged to provide a pressure drop to draw the sand laden fluid into the chamber and a mixing time within the chamber before sand laden fluid of lower viscosity exits the chamber to travel to the surface. Additional features include blades on the tool for breaking up obstructions prior to being drawn into the chamber and a lubricating line through the tool to introduce lubricating fluid to the blades.

Downhole mixing tool

A downhole tool comprises a tubular body (12) for location in a tubular member, such as a drill string, and defines a through bore (20) and a number of circumferentially spaced ports (26). A valve member which may be in the form of a piston sleeve (24) is mounted in the bore (20) and is movable relative to the body (12) between a first position in which fluid may flow through the port (26) and a second position in which the valve member (24) closes the port (26), the valve member being movable between the first and second positions by application of differential fluid pressure. Movement of the valve member (24) is provided by a cam arrangement including a circumferentially extending cam groove (56) and a cam follower (57).

Downhole tool

2-Stage underreamer

A tool for the cleaning and conditioning of tubular structures, such as well casings, comprises a central mandrel (1) upon which are mounted a plurality of interchangeable sleeves (4-9). The sleeves at each end bear stabilization elements enabling the tool to be used in a well casing of any disposition and the intermediate sleeves bear conditioning or cleaning elements (12) angularly spaced apart and separated by fluid channels (13), the cleaning elements of adjacent sleeves being off-set to form a substantially helical pattern of cleaning elements and channels to ensure 360.degree. of coverage as a tool is axially displaced within a well casing. The sleeves are mounted in such a way that relative rotation between them and the mandrel is prevented by a combination of keyways and of drive faces between adjacent sleeves formed by cut-away portions.

Tool for cleaning or conditioning tubular structures such as well casings

Shut-in tool

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.

Downhole pressure and/or temperature gauges

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. Resilient springs act on the slide blocks so as to bias the arms of each linkage towards one another whereby the common pivot axes of the arms are moved away from the elongate member, and rollers or anti-friction members are mounted at the pivot of each linkage of each pair of arms so that the device as a whole can move with minimum friction within the pipe or tube containing the device.

Centralizing devices for use in bore-holes

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.

Centralizing devices for use down-well

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.

Seal for incorporation in high pressure leak testing tool

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.

Growing community of inventors

Montrose, United Kingdom

Richard Alvin Armell