WELL STRENGTHENING METHOD Russian patent published in 1997 - IPC

FIELD: oil and gas industry. SUBSTANCE: this relates to drilling wells for oil, gas and water. According to method, casing string is lowered into bore-hole, and plugging solution is injected into hole clearance until it appears at bore-hole head. Plugging solution emerged at bore-hole head is injected again into casing string. Created is direct or return circulation of solution which is effected through averaging vessel installed at bore-hole head. In process of continuous circulation, plugging solution in averaging vessel is heated. Continuous circulation is performed stoplessly until plugging solution starts hardening. During this process, properties of plugging solution are being checked and regulated at bore-hole head at periods of heating plugging solution in averaging vessel. EFFECT: improved quality of well strengthening with levelling of periods of plugging solution hardening over entire height well shaft.