Having safe effective annular barriers that can be used for annular isolation is the key for managing wells. This has traditionally been done by either cementing the annulus or through the use of swellable packers.
The use of cement as annular isolation usually is considered as the industry standard, however it is a complicated, time-consuming and expensive to deploy. Alternatives, such as polymer-based swellable packers, are usually less complicated to deploy, but the degradable polymers invoke a risk in the typically harsh environment of a well.
The approach presented is based on a solid metal expandable system developed for the applications where swellable external casing packers traditionally have been used. The well annular barrier provides long term robust and reliable zonal isolation in cemented or un-cemented wellbores and may be used in conjunction with casing as well as liners. It also provides higher differential pressure capacity and higher expansion ratio to running OD without compromising the inner diameter. Consequently it does not impair or restrict flow conditions and furthermore enables subsequent well maintenance to take place unhindered.
The paper presents the results of the development and testing of the new solid metal expandable system for external casing applications and discuss the rationality behind the technology as well as the experience gained.