Steam injection has become a commonly used enhanced oil recovery (EOR) solution for producing heavy crude oil and bitumen. The goal is to heat the reservoir and reduce the oil viscosity in order to produce it. Several method have been developed including Cyclic steam stimulation (CSS) also known as “huff and puff”, Steam assisted gravity drainage (SAGD) and Steam flooding. These technologies and the temperature variations put significant stress’ on the casings, and damage can occur.
Adapting our remedial technology to meet these high temperature conditions was a real challenge. During injection the well temperature can reach 335°C (635°F) considerably reducing the possibility of using standard materials. The springback from expanded steel and the thermal variations exclude the possibility of a metal-metal seal. Using any elastomer to make the seal raises questions of ageing and product lifetime in the well, and was discarded for these high temperatures.
The technology we have developed for these applications uses stronger and more reliable materials to overcome these concerns and offer a life of the well remedial solution for damaged thermal wells with low impact on production rate.