RU98102965A - METHOD FOR CARRYING OUT REPAIR WORKS IN AN OPERATIONAL WELL - Google Patents

Claims (3)

1. A method of carrying out repair work in a production well, including pumping a calculated volume of viscoelastic composition into a well, pumping cement slurry through a tubing string with an open annular space of a well and injecting a calculated amount of displacement fluid with a closed annular space of a well, lifting a pumping string compressor pipes and the abandonment of the well for the period of the OZZ, characterized in that the estimated volume of viscoelastic composition is pumped into the well through the the tubing and place it in the interval below the lower boundary of the casing leakage, lift the tubing string to position its lower open end at the level of casing leakage before the injection of cement and above the upper boundary of the cement - after injection, this is done before the cement mortar is pumped, and the calculated amount of the squeezing liquid is chosen equal to 1.5 times the volume of the part of the pump-comp column spring pipes in cement mortar. 2. The method according to p. 1 characterized in that the column height of the viscoelastic composition in the well is determined from the condition of equilibrium of the hydrostatic pressure of the liquid column in the well and reservoir pressure and use the expression:

where H _vus is the height of the column of viscoelastic composition, m;
F _SLE - the cross-sectional area of the wellbore, m ² ;
γ _c.p is the density of the cement, kg / m ³ ;
γ _W - the density of the fluid filling the well, kg / m ³ ;
H _tsr - the height of the column of cement, m;
R is the radius of the well, m;
τ _vus - ultimate shear stress of viscoelastic composition, kg / m ² ;
K - coefficient taking into account the size of the caverns (K≥1).  3. The method according to claim 1, characterized in that the lower open end of the tubing string when it is raised after the cement slurry is pumped is placed 50 m above its upper boundary.