Abstract: Apparatus for use to facilitate threading and unthreading substantially vertical lengths of pipe on a drilling rig by moving the pipe between the well bore center line and a racking assembly. An arm having a gripping head mounted thereon is extendable and retractable relative to a carriage mounted on the drilling rig working board. When storing pipe, the lower end of each pipe is set on a support assembly which includes a plurality of switches which signal the position of each pipe thereon. The arm and carriage are moved under control of a computer to an appropriate slot for storing the upper end of the pipe stand. When running pipe into the well bore, the arm and carriage move the upper end of the pipe to the center line of the well and when the traveling block of the drilling rig picks up the pipe, a signal generated by the switch beneath the pipe causes the carriage and arm to move to the location for unracking the next stand of pipe.

Abstract: Method and apparatus for calibrating a material-spreading applicator. A broadcast spreader or planter is moved over a field for a measured length. The amount of fertilizer or seed which the applicator would have spread over the surface while it was so moved is caught. The area on which the caught material would have been spread is calculated and the caught material is weighed. Thereafter the weight of the caught material is divided by the calculated area. Another aspect of the invention comprises a weighing apparatus having an elongate arm with a weight slidable therealong. A container having a conical shape is mounted on one end of the arm and a support is pivotally attached to the arm between the container and the weight.

Abstract: A jacketed valve in which an annular jacket or ring is received over a wafer-type check valve. The ring includes eight axial bores therethrough spaced at 45.degree. intervals to accommodate flange studs when the jacketed valve is received between a pair of pipe flanges. In one embodiment, the annular ring is split in half along a plane normal to the ring axis.

Abstract: Apparatus for mounting a trailer hitch on a vehicle. An elongate frame having a planar base includes a pair of ends upturned at an angle substantially less than ninety degrees. A pair of elongate planar support brackets extend at right angles to the base from each end. A rear vehicle bumper is mounted on the base opposite from the extended brackets which are used to mount the bumper-and-frame combination on a vehicle. The base includes a hole for mounting a trailer hitch thereon.

Abstract: Apparatus for measuring length of an elongate cable. A frame having a hole therethrough includes a pair of rollers mounted for rotation thereon. The circumferences of the rollers are rollingly engaged with one another over the hole and a cable which is to be measured is held between the rollers and passed downwardly through the hole thereby rotating the rollers. A magnet is mounted on one of the rollers adjacent the circumference thereof. Mounted on the frame adjacent the circumference of the roller having the magnet mounted thereon is a magnetically-activated switch which closes each time the magnet passes thereby. The switch provides an input to a transmitter which generates a signal including pulses indicative of the number of rotations of the wheel having the magnet mounted thereon.

Abstract: An apparatus for driving fence posts. An inner pipe is received within an outer pipe for coaxial sliding relative thereto. The outer pipe is mounted on a vehicle in a substantially upright position. A cable is journaled over a pulley mounted on the top of the inner pipe. One end of the cable is fixed to the outer pipe while the other end is wound on a winch mounted on a platform attached to the outer pipe. A spring biases the inner pipe upwardly in order to maintain the journaled engagement of the cable and the pulley. When the winch is turned on, the inner pipe is forced downwardly thus driving into the ground a fence post positioned within said outer pipe beneath said inner pipe.

Abstract: Apparatus for controlling a brake on a drawworks having cable wound thereon. A tension gauge detects the tension in the cable which is displayed on a switch gauge. A pulse generator provides periodic pulses to one side of a relay having a set of normally open contacts. When the tension is at or above a preselected level, the other side of the relay is grounded. The relay contacts pulse a pneumatic relay which is connected to a ram that operates the drawworks brakes. When tension is at or below a preselected level, a second pneumatic relay is actuated for maintaining the ram in a brake activating condition. A switch is connected to a third pneumatic relay, which in turn is connected to the ram to permit manual brake activation and deactivation.

Abstract: A retrievable well tool which can be lowered into a well casing and set on a wire line and thereafter moved for resetting or retrieval with a drill string. The tool includes a body having expandable slips mounted thereabout for anchoring with the casing. Drag blocks which are longitudinally slidable along the body slide from a first to a second position to expand the slips. A lug on the drag blocks is received into a channel on the body. Manipulation of the plug body effects locking the drag blocks into their first position. Shear bolts maintain the drag blocks in their first position when the tool is initially lowered into the casing on a wire line. A shiftable abutment adjacent the drag blocks is selectively operated to shear the bolts and shift the drag blocks to their second position to anchor the tool.

Abstract: A pipe trough for transporting pipe between upper and lower positions. A pipe carrier having a V-shaped cross-section is received within an elongate trough body having a V-shaped cross-section. The pipe carrier is longitudinally slidable along the trough and is constructed to receive one end of a pipe. A roller is mounted at one end of the trough body for supporting the other end of a pipe received within the carrier. A hydraulic motor is provided for selectively moving the carrier along the length of the trough body. Openings formed crosswise of the trough are distributed along its length. Each opening includes a pipe unloading arm having a pivotal connection to the trough at one side. A ram positioned beneath the arm and having one end pivotally attached to the arm and the other end pivotally attached to the trough is provided for raising and lowering the arm to unload the pipe from the trough.

Abstract: A reamer for reaming the bell of plastic pipe. A cylindrical housing includes a cylindrical cavity communicating with the lower end of the housing. A downward facing annular shoulder is formed about the circumference of the cavity. The top of the housing includes a bore having a shaft threadably engaged therein. The shaft is concentric with the cavity and includes a reamer at its lower end for reaming the bell of a pipe abutted against the shoulder.

Abstract: A calibratable turbine wheel gas meter includes a tube member having a lateral stud which carries a counter. An exchangeable measuring insert comprises an inlet member including an inlet body and an outlet member including an outlet body and is inserted into the tube member to abut a stop formed in the outlet member. Together with the tube member the inlet member forms a pressure space to measure the static pressure therein. The outlet member is formed integrally with the outlet body and is combined overlappingly with the inlet member. The inlet member and the outlet member define a passage in which the blades of a turbine wheel are located and the shaft of the turbine wheel is journalled in a bearing housing disposed in the outlet body. A pulse generator is arranged to cooperate with the turbine wheel and generates pulses, the number of which is dependent on the volume of gas passing through the passage. Each measuring insert is calibrated by comparison to a standard measuring insert.

Abstract: Apparatus for setting in a bore a well tool of the type having radially expandable anchor means and a mandrel-actuated slidable valve for permitting flow through the tool. Inner and outer sleeves are telescopically interengaged for suspension from a conduit string for lowering into a well bore. A shearable tension sleeve connects the tool to the lower end of the inner sleeve. A vertically shiftable mandrel having a longitudinal bore therethrough is received within the inner sleeve for engaging the well tool valve. A ball is received within a slot in the inner sleeve and is urged into a groove formed in the mandrel by a locking collar disposed about the inner sleeve. Annular pistons are provided between the inner and outer sleeves for moving the inner sleeve upwardly responsive to pressurization of the conduit string. Such upward movement shifts the mandrel downwardly with respect to the inner sleeve and shifts the locking collar to effect locking of the inner sleeve to the mandrel in its shifted position.

Abstract: A retrievable bridge plug of the type having upper and lower anchors and an elastomeric packer for sealing a well casing. Drill string manipulation of the plug body effects packer compression and sealing. A ratchet maintains packer compression when engaged and permits packer expansion when disengaged. A cam surface on the plug body engages and disengages the ratchet responsive to longitudinal movement of the plug body.

Abstract: Apparatus adapted to be lowered on a tubing string for setting a gravel pack at the bottom of a well. Conduits provide a gravel-slurry flow path from the bottom of the tubing to a screen which is suspended from a housing at the lower end of the conduits. A packer is provided between the tubing and the housing for sealing the well bore during gravel packing. When the screen hits the bottom of the well, a clutch connected between the housing and the conduit disengages to prevent transmission of tubing movement to the screen during the gravel packing process. Upon packing completion, tubing string rotation releases the screen to permit raising of the apparatus on the tubing string.

Abstract: A subtractive color printing device for use between a source of white light and a color transparency or negative intended to be exposed to at least a portion of the spectrum of such source. An aperture is disposed in the exposure path between the light source and the negative. A plurality of color filters, each mounted on a separate carrier frame, are positioned for independent adjustment to different positions between one position fully exposing and another position fully spanning the aperture. Each filter carrier is driven to such different positions by a motor. A computer is programmed to power the motors, upon a user input, to drive the filter carriers to preselected positions.