Teleco Oilfield Services Inc.

Baker Hughes Corporation

Frederick A Stone

Robert J Maron

Martin E Cobern

Ralph F Spinnler

Charles W Helm

Stephen Nicholas Wallace

Edmund M Hamlin

Donald Grosso

Normand P Holcomb

A method is presented for obtaining borehole measurements using measurement-while-drilling apparatus wherein mud pulse telemetry signals are decoded from the annulus pressure signals (as opposed to the standpipe pressure signals). The data bearing signals are enhanced by combining the annulus pressure signals and standpipe pressure signals using addition, multiplication or correlation techniques.

Method of decoding MWD signals using annular pressure signals

A method is presented, for use in borehole drilling, for correcting errors in azimuth determination resulting from variations in the earth's magnetic field to which a measuring instrument is exposed. The method distinguishes between variations in the earth's magnetic field caused by the drillstring and variation caused by external sources, and the method corrects only for errors caused by the drillstring. If the error is caused by the drillstring, an azimuth correction is made based on dip angle data, thereby reducing errors caused by scale factor variations since dip angle is a ratio quantity of magnetic field components.

Method for the detection and correction of magnetic interference in the

An insulating coupling for drill collars and a method of manufacture thereof are presented wherein the coupling consists of an electrically insulating ceramic coating applied in thickness from 0.002 to 0.006 inch to the threads of the coupling by a detonation gun process and sealed with an epoxy sealer to reduce porosity.

Insulating coupling for drill collars and method of manufacture thereof

Method of manufacturing an insulating coupling for drill collars

A flexible electrical connector for borehole telemetry apparatus is presented wherein the electrical connector includes an elongated metal tube having an intermediate section coiled around the exhaust shroud of a mud turbine. Electrical conductors are housed within the metal tube, and the tube is internally pressurized with oil, the pressure of the oil being maintained equal to the drilling mud pressure by a bellows exposed to the drilling mud.

Electrical connector for borehole telemetry apparatus

A hydraulic circuit for borehole telemetry apparatus is presented wherein a mud pulse valve is operated by hydraulic pressure applied to differential areas of an actuating piston. The system includes a hydraulic pump, a filter in the line between the pump and the piston to be actuated, an accumulator upstream of the filter, a regulating and relief valve downstream of the filter, and solenoid actuated valves to control delivery of hydraulic fluid to the piston. The system also includes a pressure compensating bellows to compensate for changes in pressure in the drilling mud.

Hydraulic circuit for borehole telemetry apparatus

A mounting assembly and shock absorber are presented for mounting and shock absorption for the transmitter and sensor elements of a mud pulse telemetry system. The shock absorbing apparatus for the mud pulse transmitter is entirely located at one end of the assembly above the transmitter, and the shock absorber apparatus for the sensor package is located at the other end of the assembly below the sensor package, whereby all of the elements can be incorporated in a one piece drill collar.

Growing community of inventors

Durham, CT, United States of America

Frederick A Stone