DEVICE CHECKING LEAKAGES BEYOND STRING Russian patent published in 1996 - IPC

FIELD: drilling. SUBSTANCE: invention deals with drilling of gas and oil wells. Device includes string which carries hollow container with solution of "labelled" fluid and unit for container puncture. Sleeve with through radial holes is located outside of string. Container is formed by outer surface of string and sleeve, it has upper and lower pistons. They divide container space into chambers above pistons, between pistons and under pistons. Chamber above pistons is filled with air. Solution of "labelled" fluid is poured into chamber between pistons. Unit for container puncture is positioned in chamber under pistons and is manufactured in the form of powder charge and includes elements of electric ignition. EFFECT: improved functional efficiency. 2 dwg