WELL CLEANING METHOD Russian patent published in 2012 - IPC E21B37/00 

FIELD: oil and gas industry.

SUBSTANCE: during implementation of the method the following is performed: well is separated above perforation interval of productive formation by packer; space under packer is connected to wellhead by pipe string; space of pipe string above packer is separated by spring-loaded valve; space of pipe string above spring-loaded valve is connected to intertube space of well; pipe string above place of connection with intertube space is separated from valve by plunger; fluid is extracted from space of pipe string above plunger with valve and from intertube space until current pressure in well is reached; pressure in pipe string from wellhead is increased; spring-loaded valve is opened and space under packer is connected to intertube space.

EFFECT: improving the cleaning quality.

1 dwg