TELEMETERING SYSTEM USING POSITIVE PULSES OF DRILLING MUD PRESSURE FOR INFORMATION TRANSMISSION Russian patent published in 2002 - IPC

FIELD: well drilling; applicable in control of bottom-hole parameters in well drilling. SUBSTANCE: telemetering system has body of downhole instrument with diaphragm shutting-off the flow section of drill string. Mounted in body are control valve with drive and working valve consisting of piston, valve and rod made integral and having through hole. Novelty consists in that body has inlet and outlet windows and window of pressure release located between control valve and its seat. Control valve has a hole. It is sealed relative to body. In working valve, valve proper is located between piston and rod, with rod located in upper part and acting as additional piston. Working valve seat is installed between inlet and outlet windows. Working valve may be centralized in body with the help of rod and piston. Drive of control valve may be made in the form of solenoid with return spring and is installed in separate cavity in body of downhole instrument. EFFECT: higher reliability of system and reduced its sluggishness. 3 cl, 1 dwg