METHOD OF WELL ABANDONMENT WITH COLLAPSED PRODUCTION STRING Russian patent published in 2010 - IPC E21B33/13 

FIELD: oil and gas industry.

SUBSTANCE: well is killed, tubing string is removed, sand plug is washed and collapse of production string is improved. Section of pipes is lowered to straightened production string thus covering the T/pay with no admittance of its shoe to head of washed sand plug for 1-2 m. Section of pipes is cemented with its being pressed to the head of sand plug, and after WOC there performed is cementing of inner cavity of section of pipes. Well shaft above cemented section of pipes is filled with killing fluid and cement bridges are installed at shoes of technical columns and surface pipe. Well shaft is filled with killing fluid between cement bridges, and at the interval of permafrost formations with non-freezing solution. Wellhead equipment is removed and concrete stand with datum point is installed. Or blind plug is installed in well shaft, inner cavities of wellhead equipment are filled with cement solution above blind plug, and side taps and upper flange of wellhead equipment is sealed with blind flanges with installation of datum point.

EFFECT: reliable well abandonment at minimum capital costs.

2 dwg