METHOD FOR WELL CASING PIPE DEFORMATION PREVENTION WITHIN PLASTIC SALT DEFORMATION INTERVAL Russian patent published in 2006 - IPC E21B33/14 

FIELD: oil and gas industry, particularly to provide casing pipe stability in chemical deposits.

SUBSTANCE: method involves removing stresses acting on casing pipes during deep prospect well drilling, wherein the stress is appeared due to side rock pressure acted on casing pipe from salt massif side. To provide above stress removal orifice system is created in casing pipe in lower part of salt massif, namely in salt massif bottom, and in upper part of salt massif, namely in salt massif roof, with the use of hammer drill. Then salt is dissolved with fresh drilling fluid flow circulating from salt massif bottom to salt massif roof through orifice system in casing pipe. Fresh fluid is supplied through flow strings having dividing packer. Salt dissolving and stress releasing is monitored by temperature reduction with respect to background temperature defined by data obtained from temperature survey and acoustic cement bond logging. Then casing annuity is plugged by filling the casing annuity with cement.

EFFECT: increased casing pipe stability.