Gas Research Institute

The Charles Machine Works, Inc.

Douglas W Lee

Gerald A Stangl

Arthur D Deken

Curtis E Leitko, Jr

Dirk A Wilson

Richard P Dunn

James E Franklin

Michael R Wasson

A method and apparatus for drilling a horizontal controlled borehole in the earth includes a drill frame, a drill string and a downhole tool. The drill frame includes a wrench attached to the frame for assisting in breaking and forming joints. The downhole tool includes removable blade assemblies having, for example, stepped or spade-like profiles and hard facing at areas of primary contact with the soil. When fluid is added for cooling, lubricating and flushing away cuttings, the downhole tool can include a nozzle parallel to the centerline of the longitudinal axis of the drill string, a check valve means for preventing downhole particles from entering the fluid passageway and/or a transmitter protecting waterproof plug for diverting fluid to a fluid passageway and for allowing an on-board downhole transmitter to be near the drill bit. Also, the blade assembly can be placed so as to divert fluid from the nozzle to an acute angle relative to the longitudinal axis of the drill string. Alternative embodiments also include placing the fluid metering device rearward of the tool body.

Apparatus for drilling a horizontal controlled borehole in the earth

A manually operated downhole for an underground earth boring apparatus having a pneumatically operated earth boring tool. A drill pipe is connected to the tool and to a source of pneumatic fluid. A valve is positioned in the drill pipe substantially adjacent to the tool between the tool and the source of pneumatic fluid. This downhole valve controls the flow of pneumatic fluid to the tool. The valve is operable in response to pushing or pulling on the drill pipe.

Method of providing a high pressure surge of working fluid to an

Downhole surge valve for earth boring apparatus

A percussive mole boring device with a location transmitter is disclosed. The transmitter is located in a forward end of a drilling assembly attached to a mole to accurately transmit the location of a boring element or cutting surface to surface detector. The transmitter is surrounded on each end by isolator means which protect the transmitter from damage due to shock created by the percussive device, e.g., a hammer driven by compressed air. In one embodiment the transmitter is located beneath a single window transparent to the transmission frequency, and the cutting surface of the bore is angled. Therefore, the travel direction of the mole can be controlled by rotating the cutting surface to a desired inclination and terminating rotation during forward motion for a short period. The mole travels in a straight path during ordinary travel due to rotation. In a second embodiment, the transmitter is located beneath three equiangularly displacent windows to create a continuous field for detection. This type of mole is not steerable and includes a boring element with a non-angled edge. In a third embodiment which is similar to the second embodiment, the windows are not present, and a transmitter coil is wound in an external groove of the drilling assembly and is covered by epoxy.

Percussive mole boring device with electronic transmitter

An earth boring apparatus has a pneumatically operated earth boring tool, a flexible conduit or drill pipe connected to the tool and to a source of pneumatic fluid. The tool has an earth boring member and a reciprocally movable hammer positioned in the tool to apply a percussive force. A valve assembly in the flexible conduit or drill pipe substantially adjacent to the tool between the tool and the source of pneumatic fluid controls the flow of pneumatic fluid to the tool. The valve assembly has a pneumatic pressure-operated valve which is operable in response to the pressure of pneumatic fluid in the flexible conduit or drill pipe to be opened to permit flow of pneumatic fluid to the tool at a predetermined operating pressure to transmit an initial pulse of pneumatic fluid to initiate operation of the hammer. The valve is kept open at a lower pressure than that required to open it. One form of the valve is a pressure operated valve, spring-loaded toward closed position, which opens at a first predetermined pneumatic pressure permitting flow to said tool and closes at a second, substantially lower, pneumatic pressure. Another form of the valve means has a valve, spring-loaded toward closed position, which opens in response to pneumatic conduit pressure, and spring loaded ball detents or a pneumatic pressure operated latch to secure the valve in an open position. The latch and valve are operated to closed position at a lower pressure.

Growing community of inventors

Enid, OK, United States of America

Douglas W Lee