SEALING OF OIL STRING Russian patent published in 2014 - IPC E21B33/124 

FIELD: oil-and-gas industry.

SUBSTANCE: prior to sealing, bed is temporarily locked by self-decomposing after checking the bottom packer tightness. The following components are assembled at well mouth, from bottom to top: bottom packer, pipe in length exceeding intervals of disturbance, top packer, left adapter and two-way valve. Said set is downed at setting tool into oil string in its sealing interval. Then, packers are simultaneously set. Thereafter tightness of top and bottom packers setting is tested by decreasing the fluid level in oil string by swabbing relative to setting tool. Note here that, first, bottom packet setting tightness is tested and, then, that of the top packer. In case setting of both packers is tight, setting tool is rotated clockwise to withdraw it with two-way valve from oil string to the surface. In case even one of said packers leaks, both are withdrawn. Thereafter, abode described jobs of temporarily blocking, downing, setting and testing are performed.

EFFECT: higher efficiency, simplified procedure.

4 dwg