You don’t need to look far before a Single Point of Failure (SPOF) gets some hard press, from “…SPOF is essentially a flaw in the design, configuration, or implementation of a system” to “SPOFs are undesirable in any system with a goal of high availability or reliability”. Engineers in the well construction industry are often tasked with de-risking their operations and, arguably, their most valuable time spent can be attributed to preventing SPOFs.
The deal with the seals
Sealing of subsea wellhead running tools within wellhead systems are impressively reliable. They must be, as typically they are the only barrier of pressure integrity between a successful primary cement job and a major Non-Productive Time (NPT) event. Prior to SeaCure®, DeltaTek’s proprietary stabbed in inner string cementing system, it was not possible to pressure test seals at the wellsite, whilst being reliant on them maintaining effectiveness for the circulation of wellbore fluids and cement slurry when installing the casing string.
Through DeltaTek’s SeaCure® system, the primary seals for the circulation of wellbore fluids and cement slurries are moved to the float shoe itself via a triple seal stack within an engineered bore. The high reliability wellhead running tool seal becomes the back-up, giving ultimate cement placement control, de-risking a major Single Point of Failure within high criticality operations, and enabling operators to have a more predictable outcome to their subsea casing cement jobs.
As well as giving an additional barrier of pressure integrity defense to the wellhead running tool seals, SeaCure® allows the ability to pressure test redundant seals within the wellhead at the wellsite, following make-up. This pre-installation casing pressure test gives confidence that not only the primary SeaCure® inner string seals are effective but also that the casing couplings all have hydraulic integrity, with the back-up seals in the wellhead running tool ready to do their job, if and when required.
“SeaCure® is a very good system, the inner string was sealed off in the float shoe and it effectively allowed the wellhead tool seals to become a secondary, completely eliminating potential single ball valve failure during cementing on a high profile well.” Subsea Supervisor, SeaCure® customer operator.
If you’d like to learn more about our SeaCure® services in subsea applications, please drop us a line at firstname.lastname@example.org.