METHOD FOR CLEANING A DOWNHOLE ROD PUMPING UNIT FROM ASPHALTENE-RESIN-PARAFFIN DEPOSITS WHEN A STRING OF SUCKER RODS HANGS Russian patent published in 2022 - IPC E21B37/00 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to the oil and gas industry, and in particular to thermal methods for well cleaning. The method includes the use of tubing string for heating and steam injection into the annulus of the well with circulation of the well fluid using a sucker-rod pump (SRP) with suction and discharge valves and control of the load on the rods. Before steam injection, the wellhead stuffing box is dismantled, the solvent for asphaltene-resin-paraffin deposits (ARPD) is poured in a volume of 10-15 liters into the tubing string, and left for reaction. A variable frequency drive (VFD) is connected to the control station of the SRP drive, the number of swings of the SRP drive balancer is reduced to 0.5-1 swings per minute, depending on the amount of deposits, the manifold is disassembled with connection to the trough tank, the SRP drive is put into operation with a reduced number rocking of the balancer and pumping the well fluid into the trough tank to exit the residues of the ARPD plug. A manifold with a collection system is assembled, a mobile steam generation unit (SGU) is connected to the annular valve, and steam is injected into the annular space of the well with a reduced number of drive balancer swings for 2 hours. The number of swings of the SRP drive balancer is increased by 0.5 swings per minute with the help of VFD up to the initial one every 15-30 minutes, depending on the amount of deposits with control of the load on the rods according to the dynamometer chart. The VFD is turned off and the pumping of the manifold steam is stopped if there are no signs of hanging of the sucker rod string.

EFFECT: efficiency of cleaning is increased when used in wells with inoperable pumping equipment due to the simplification of the technology, accidents are excluded.

2 cl, 2 dwg