SEPARATE MAINTENANCE PROCESS FOR INJECTION OR PRODUCTION WELL AND IMPLEMENTATION VARIANTS Russian patent published in 2008 - IPC E21B43/14 

FIELD: mining.

SUBSTANCE: process involves consequential downtake of two pipe strings of larger and smaller diameter, placed one into another, into injection, flowing, pumping or gaslift well. Pipe string of larger diameter is equipped with at least one packer and one bypass group or element for streaming working medium of fluid extracted. At least two targets of one well are operated at the same time. According to the invention, sealed feedthrough cavities of the pipe strings of larger and smaller diameter are dissociated at the depth higher or deeper of the upper target, so that the media were transported by the pipes separately. One cavity is connected hydraulically to the effective drainage area of the upper target by the bypass group or element, and another cavity is connected to the effective drainage area of the lower target. At that, the bypass group or element has either axial landing channel or landing joint at the bottom. Pipe string of smaller diameter features dissociating element, which is installed either in axial landing channel of the bypass group or in the landing joint below the bypass element. Two device variants are offered for implementation of the process.

EFFECT: higher technology efficiency and reliability by dual maintenance.

26 cl, 15 dwg