Patent ID: 9151144
Filing Date: 2015-10-06
Classification: E21B

Abstract:
1. Method of well casing for thermal oil recovery, implemented by means of an expandable sand screen which comprises casing a well bore that has been drilled to the top of productive formation with a casing string, drilling through the productive formation with a bit of smaller diameter than that used to drill the bore to the top of the productive formation, running-in the sand screen to the productive formation, creating an excess pressure to the sand screen and tightly connecting it by an anchor with the casing string of the well bore to the top of the productive formation, and subsequent drainage or heat-carrier injection into the formation through the sand screen, wherein the sand screen is pre-assembled of longitudinally-corrugated pipes with slots, mutually connected by end cylindrical portions with a limited longitudinal shift possibility, and the sand screen slots are internally hermetically sealed with a thermoplastic material, and after run-in said excess pressure is applied to the sand screen so that it is expanded along its entire length, except for its cylindrical portions, whereupon a heat carrier is supplied into the sand screen, and thermoplastic material melts, unsealing the slots.