PROCESS TESTING TIGHTNESS OF OPERATIONAL STRING IN INJECTION WELL Russian patent published in 2001 - IPC

FIELD: oil production industry. SUBSTANCE: operational mode of well is changed by closing partly gate valve across well-head: flow rate of fluid decreases by 30-50% of initial value. Pressure change ΔP is recorded in time interval Δt from moment of change of operational mode of well in process of which maximum rate of pressure drop is observed till it stabilizes. Coefficient of pressure drop K₁ is determined as ΔP/Δt. Coefficient K₂ of pressure drop curve is found in same manner at least once a year. K₁ and K₂ are compared. If K₂ ≤ K₁, then operational string is tight. If K₂ > K₁ and no work to raise penetrability of pool in this well was conducted then operational string is not tight. In the last case well is examined additionally with use of geophysical instruments to define more exactly character and point of loss of tightness of operational string. EFFECT: simplified approach to testing and reduced time for realization of process. 1 cl, 1 dwg