METHOD OF SHUT-OFF AND RESTRAINT OF WATER PRODUCTION IN WELLS Russian patent published in 2009 - IPC E21B33/13 C09K8/512 

FIELD: mining.

SUBSTANCE: method can be implemented at shut-off of drill string casing and casing string borehole annulus, at sealing casing strings, at sealing threaded connections and shutting-off watered interlayers in oil and gas wells. According to the method the shut-off and restraint of water production in wells consists in pumping into a well an insulating material containing formaldehyde resin, an initiator of polymerisation and water, also in forcing this material through and in holding it for solidifying and hardening; the insulating material as formaldehyde resin contains urea-formaldehyde or acetone- formaldehyde resin and additionally - oxy-ethylated isononylphenols, oxy-ethylated monoalkylphenols or their mixture, natural or synthetic rubber or their mixture at the following combination of components, wt %: urea-formaldehyde or acetone- formaldehyde resin 20.0-70.0, oxy-ethylated isononylphenols, oxy-ethylated monoalkylphenols or their mixture 0.5-4.0, natural or synthetic rubber or their mixture 0.05-50.0, polymerisation initiator 0.5-3.0, water - the rest.

EFFECT: upgraded quality of water producing zones shut-off in producing and pressure wells under various geological, physical and thermo-baric conditions.

5 cl, 4 tbl, 8 ex