METHOD OF LEAKAGE TEST OF INJECTION WELL FLOW STRING Russian patent published in 2003 - IPC

FIELD: oil production. SUBSTANCE: method provides for variation of well operating conditions by closing gate on wellhead, with subsequent recording of pressure variation. In so doing, flow rate of injected fluid is reduced down to 30-80% of initial value, and pressure variation is recorded in time interval since moment of well operating conditions change, in course of which maximum pressure drop rate is observed until its stabilization. In this case, coefficients of pressure drop curve K₁ and K₂ are determined by calculation. Flow string is leaking if K₂>K₁, provided no jobs were conducted for increase of formation permeability after determination of K₁. EFFECT: provided operative monitoring of flow string sealing in injections wells. 1 dwg