Abstract: An indicator for a pilot, particularly a two-line pilot to visually indicate whether a pilot has responded to a pressure condition within a flowline which pressure condition is outside a predetermined range. The visual indication also indicates whether the pressure condition is above or below the predetermined range.

Abstract: An emergency shut-down system to close a gate valve in a pipeline and therefore terminate flow. The closing action is initiated when a pilot valve senses pressure in the pipeline outside predetermined limits. This reduces the signal pressure in the system which, in turn, causes a fluid dump from the gate valve actuator which closes the gate valve and terminates fluid flow in the pipeline. The system is reactivated by manually pumping the system which re-opens the gate valve and allows fluid flow in the pipeline to again continue.

Abstract: A two line pilot valve used to exhaust hydraulic fluid from a control circuit when the operating conditions within which a flowline is intended to operate are outside of predetermined limits. The pilot exhausts fluid within a control circuit to a reservoir which allows a dump valve to dump fluid from an actuator which causes the actuator to close the flowline. The pilot has a first poppet sleeve which contacts an o-ring. When the poppet sleeve and o-ring separate, fluid is allowed to pass from the inlet port of the pilot to the exit port and thereby exhaust the fluid of the control circuit.

Abstract: An emergency shut-down system to close a gate valve in a pipeline and therefore terminate flow. The closing action is initiated when a pilot valve senses pressure in the pipeline outside predetermined limits. This reduces the signal pressure in the system which, in turn, causes a fluid dump from the gate valve actuator which closes the gate valve and terminates fluid flow in the pipeline. The system is reactivated by manually pumping the system which re-opens the gate valve and allows fluid flow in the pipeline to again continue.

Abstract: A cushion connector (10) used for above ground drilling has pin (11) and box (12) components at opposite ends. A housing (13) extends axially between the pin and box components. A drive spline (22) is operably connected to one of the components and extends outwardly from the axis (23) of the cushion connector (10). A plurality of drive blocks (24) extend inwardly from the inside diameter of the housing (13) and engage with keyways (69) of the drive spline (22). Drive lugs (71) connected to the inside of the housing (13) act on the drive blocks (24) and resilient cushion blocks (70). A spring (30, 60) extends between the pin (11) and box (12) components within the housing (13) and exerts axial force between them. The drive splines (22) are coaxial with the connector (10) and move axially under operation. Cushion blocks (70) are provided between the drive blocks (24) and drive lugs (71).

Abstract: An emergency shut-down system to close a gate valve in a pipeline and therefore terminate flow. The closing action is initiated when a pilot valve senses pressure in the pipeline outside predetermined limits. This reduces the signal pressure in the system which, in turn, causes a fluid dump from the gate valve actuator which closes the gate valve and terminates fluid flow in the pipeline. The system is reactivated by manually pumping the system which re-opens the gate valve and allows fluid flow in the pipeline to again continue.

Abstract: A floating cushion connection member is operable between a power head and a drill string member. A first cap member is mounted about the periphery of a piston. A washpipe extends from within the bore of the piston to a mounting area in a second cap member. A body member connects the first and second cap members. A spline member in the form of drive pins located between the body member and the piston rotate the piston with the body member and second cap member and allow the piston to move axially relative to the body member and the second cap member. The washpipe has limited angular movement within the second cap member and the piston. Cushion members are provided between the second cap member and the piston and the piston and the first cap member, respectively.

Abstract: A mobile drilling apparatus having a support structure, a mast positioned on the support structure, a drill head and a hydraulic assembly vertically operable on and guided by the mast. The hydraulic assembly moves the drill head and includes lower hydraulic cylinders rigidly connected to the mast and upper cylinders, each mounted inside and connected rigidly to a tube. A piston rod with connected upper and lower pistons is movable within the upper and lower hydraulic cylinders. The drill head is connected to the lower portion of the tube.

Abstract: A wellhead sealing system comprises a casing, a tubing spool and a bushing between the casing and tubing spool. A first recess is provided in the bushing and a first casing seal is mounted therein to act between the bushing and the casing. A second recess is provided in the tubing spool and a first bushing seal is mounted therein to act between the tubing spool and the bushing. The casing seal has cylindrical inside and outside surfaces located generally at the inside and outside diameters of the seal. The cylindrical inside surface is defined by a radially inwardly extending convex central protuberance and opposed cylindrical flat surface areas extending axially outwardly from the convex central protuberance into first transition areas extending to respective end surfaces. The outside surface is defined by a circumferential centrally located groove flanked by axially outwardly extending flexible retaining flanges forming second transition areas between the cylindrical outside surface and the end surfaces.

Abstract: A casing hanger for hanging well casing and sealing the well pressure from the atmosphere. The casing hanger comprises a cooperating slip and slip bowl adapted to grip and retain the well casing when they abut a cooperating shoulder on the casing head whereupon the casing hanger will be in its operating position. A seal is adapted to be compressed when the casing hanger is moved downwardly and forms the seal when the casing hanger reaches its operating position. A manually adjustable bolt can increase or decrease the seal pressure without disturbing the well casing.