Abstract: Discloses a method and apparatus to help provide fluid pressure in a well bore sufficient to overcome in situ earth formation pressures by perforating a circulation port through the sidewall of a drill collar above the drill bit to provide circulation of weighted drilling fluid down through the drill spring and back up the well annulus. Includes the lowering of a chemical reactant wireline perforating tool to a designated position within a drill collar, placing a single chemical flow jet into position addressing the sidewall of the drill collar, forcing the chemical reactant through the jet under high pressure and at high temperature to react with the drill collar metal and thereby remove a portion of the metal with the remaining metal defining a fluid circulation port through the drill collar wall, and pumping fluid through the port to establish circulation.

Abstract: Downhole well tools and anchoring means therefore including a chemical cutting tool having improved slip actuating and slip array assemblies. The cutting tool includes a slip shaft provided with fluid passageway and having a slip array slidably disposed thereon. The tool further includes slip expansion means secured to the shaft adjacent to the slip array. A piston sleeve is slidably disposed on the shaft and connected to the slip array and defines a piston chamber in fluid communication with the shaft passageway such that the application of fluid pressure drives the piston sleeve and slip array to a deployed position in which the slip array is expanded. Biasing means located externally of the piston sleeve function to bias the piston sleeve to a retracted position upon release of fluid pressure. The slip array is comprised of spaced slip segments which are biased inwardly by means of cantilever springs secured to a structural member of the logging tool.

Abstract: A resilient holding device comprising a looped helical spring or a closed loop of interconnected essentially circular disc elements confined to an annular cavity circumferentially within a threaded joint or coupling. By tightening the threaded joint or coupling such as to engage the confined spring, a latching effect is created that requires a reverse torque for disassembly that exceeds the torque required to tighten. Such a torque biased threaded coupling is particularly useful in oil field applications.

Abstract: A method for testing earth formations informs the operator of the density of the formation fluid being produced before it reaches the surface. In the method, a bypass sub is secured to the drill string. The bypass sub has a bore for receiving a wireline tool that has sensing instruments. The wireline tool also has arms that will shift a sleeve to open and close the bypass sub. The wireline tool has a density measuring device for measuring the density of the formation fluid and providing a concurrent surface indication. A reversing valve is located above the bypass sub and is of a type that provides a port for reverse circulation while the wireline tool is still downhole. Preferably, the reversing valve is shifted by the wireline tool to the open position.

Abstract: An improved inclinometer and method for simultaneously measuring tilt and relative bearing in remote hostile environments such as oil and gas wells involving a pair of pendulum masses attached to perpendicularly intersecting shafts and individually capable of creating rotational motion through angles characteristic of tilt and relative bearing wherein, by use of a differential gearing system, the rotational motion induced by tilt and rotational motion induced by relative bearing are summed as a single rotational motion parallel to the axis of rotation of the relative bearing induced rotation and collinear to the well bore such that potentiometers responsive to relative bearing and the sum of tilt and relative bearing generate electrical signals that can both be transmitted to the surface without the use of troublesome slipring electrical contacts or the like. In this manner the reliability and durability of instrument is improved.

Abstract: A cylindrical downhole chemical jet cutting tool including a generally cylindrical slip body having pipe gripping slips connected to a co-axially disposed expandable piston-cylinder biased toward a retracted position by a return spring; each slip includes a pivoting head pivotally retained by the slip body and biased toward a retracted from deployed position by a garter spring. Each slip defines at least two sets of gripping teeth having different gripping faces such that each gripping face becomes substantially parallel with the tool body axis as the slip becomes deployed a different respective distance from the tool. A slip expansion mandrel disposed within the slip array deploys the slips into gripping engagement as the piston-cylinder is actuated in response to application of fluid pressure. A chemical fluid cutting means including a fluid chamber defined within the tool body between two diaphragms can rupture from application of a designated differential fluid pressure.

Abstract: Discloses apparatus and method for testing, then treating, then testing the same sealed off region of earth formation within a well bore. Employs a sealing pad arrangement carried by the well tool to seal the test region to permit flow of formation fluid from the region. A fluid sample taking arrangement in the tool is adapted to receive a fluid sample through the sealing pad from the test region and a pressure detector is connected to sense and indicate the build up of pressure from the fluid sample. A treating mechanism in the tool injects a treating fluid into said sealed test region of earth formation. A second fluid sample is taken through the sealing pad while the build up of pressure from the second fluid sample is indicated.

Abstract: Discloses an improved tool and method for cutting material by expelling a jet stream of liquid chemical reactant into forceful flowing connection and chemical reaction with a designated area of the material. Applies a continuing force to a designated first stage mass of reactant to move the first mass through a designated linear distance to accelerate the first mass and thereby provide the first mass with kinetic energy. Causes the first mass to encounter and join with a second stage mass of chemical reactant to form an aggregate mass with the aggregate mass then moving at a velocity attained by the kinetic energy of the first mass, as applied to the aggregate mass, and at a rate of acceleration generated by the continued application of said force to the aggregate mass. Passes the aggregate mass through a medium adpated to heat the said aggregate reactant mass to a substantially elevated temperature.

Abstract: A well conduit caliper tool which simultaneously measures the remaining wall thickness of a well conduit in situ and the minimum inside diameter of such conduit. A caliper feeler arm element which extends out the furthermost distance from the caliper tool activates a sensing element that produces the indication of remaining conduit wall thickness. Another caliper feeler arm element which extends out the least distance from the caliper tool activates another sensing element that produces the indication of the minimum inside diameter. At the earth's surface these indications are recorded on a continuous strip chart or log as the variation of such respective diameters through the interval of conduit measured by the caliper tool. Mechanical linkage wear compensation and linear mechanical movement through the linkage between the feeler arm elements and the sensing elements are provided.

Abstract: A tool for testing earth formations in bore-holes provides a failsafe function for retracting the sealing pad of the formation isolation device, in the form of elements operable in response to failure of down-hole power supply for the tool to effect release of hydraulic setting pressure on the seal pad. The tool further provides a formation mini-sample chamber of variable volume with elements permitting aboveground monitoring and control of same independently of any other tool function. The mini-sample chamber control device also controls the operation of a formation fluid sample flow line valve. The tool is divided into upper and lower pivotable sections to alleviate the problem of becoming differentially stuck. A unique pivot structure incorporating sample chamber seal valve assembly, is provided. A unique sand screen device is provided to permit the tool to function when working with unconsolidated formations.

Abstract: Improvement in free point indicators disclosed in U.S. Pat. No. 3,690,163. Discloses new strain sensing system having all electrical/electronic components, other than coil and diode components, located at earth's surface remote from high temperatures and shock loading. Includes a toroidal armature within the downhole tool having coils or windings to generate a pulsating magnetic flux field developed by an alternating current. A U-shaped permanent magnet is disposed such that a portion of its constant magnetic flux field occupies physical space common with a portion of the pulsating magnetic flux field for mutual influence. A diode provided in series with each winding limits electrical current passing through each winding to pulsating DC. The constant flux of the magnet and the pulsating flux of the coils are relatively positioned in opposing sense whereby the current passing through each winding is of designated magnitude.