PRODUCTION STRING LEAK TEST METHOD Russian patent published in 2005 - IPC

FIELD: oil and gas industry, particularly for oil, gas and water well operation and repair.

SUBSTANCE: method involves isolating controllable string area by sealing well head along with pressure and temperature survey instruments installed on the string with the use of string pressure testing system, wherein the pressure testing system includes drive, anchor, sealing collar and means to transmit motion from drive to anchor and sealing collar and instrument assembly having pressure and temperature survey instruments, locator to determine clutch coupling location along the string is detachably connected to pressure testing system from top thereof; lowering pressure testing system into the string towards well face; sealing, pressing thereof and removing pressure; disconnecting instrument assembly from anchor and sealing collar; lifting thereof to well head; continuously measuring medium temperature and pressure inside the string and determining clutch coupling location; detecting probable leaking intervals and air-tight upper part of the string; once more lowering instrument assembly and installing thereof in leaking interval, which is the nearest to well face; detecting leaking zones in each leaking interval by stepped moving pressure testing system in bottom-top direction.

EFFECT: decreased costs due to reduced quantity and time of technological operation performing.

10 cl, 2 dwg