METHOD FOR SEALING A PRODUCTION STRING Russian patent published in 2018 - IPC E21B33/10 

FIELD: oil and gas industry.

SUBSTANCE: invention refers to oil and gas industry, in particular, to methods of production string sealing. Method for sealing a production string comprises lowering of a packer on a setting tool to a production string of the well, setting the packer in the production string below the leakage interval with further removal of the setting tool. At the wellhead, the assembly is assembled from the bottom up: a container with a solid reagent plugged from below, a perforated branch pipe, a packer, a disconnect device, a mechanical scraper, a template, a landing tool, arrangement is downed at setting tool into production string with gaging the production string to a depth of 50 m below the packer setting interval, then the mechanical scraper is used to clean the inner walls of the production string 15 m higher and 15 m below the packer landing interval, after which the packer is placed so that it is located in the landing interval below the interval of the disruption of the production string, but above the reservoir, make the packer fit and determine the tightness of the packer insertion by pumping liquid into the reservoir until it saturates, then removing the curve of recovering the liquid level in the annulus, further the detachment device is undocked and the nipple of the disconnect device, the scraper, the template and the landing tool are extracted from the production column, then at the wellhead, a bottom-up arrangement is assembled and lowered into the production column: the nipple of the disconnect device, the pressurized saddle, a column of elevator pipes with a locking support of inserted bottom-hole pump – BHP, whereby the tubing string is lowered to a depth of 2 m to the case of the disconnecting device, the ball is dropped into the column of the elevator pipes and the pipe string is squeezed by 9.0 MPa, then by backwashing with the supply of liquid to the annulus, the ball from the tubing string is washed out, the column of the elevator pipes is discharged, and the nipple is joined in the disconnector housing, from the mouth of the well, the BHP plunger is lowered into the tubing string column on the rod string, the BHP plunger is planted in the lock support and the BHP is put into operation.

EFFECT: proposed method of sealing the production column allows to increase the likelihood of sealing the packer tightly; start the well in operation immediately after sealing the production column without additional descent of pumping equipment; increase the overhaul life of the well; reduce the costs of preparatory work before sealing the production string; exclude the blocking of the reservoir; reduce the duration of the process of sealing the production column.

1 cl, 4 dwg