Pull-up Metal Seal System for Subsea Wellhead Equipment Available to Purchase

This paper presents the design of a new pull-up metal-to-metal seal suitable for use in subsea wellheads. The development of such seals involves careful consideration of the environmental and operational requirements for subsea wellheads. The environments in which sealing systems working on must operate are necessarily harsh. This design involves special structure differed from earlier types. It's actuated by pull-up force which obtained from drill pipe. For deep water or even ultra-deep water drilling, as we all know, the whole drill string is just soft as a rope, so its elasticity is much better than compressibility, which means the pull-up force can actuate seal safely and effectively. More importantly, the unique design of wedge-shaped structure can draw back into the casing hanger, before the seal being actuated, and it can also avoid scoring damage on the seal surface during installation, because of its small diameter. A finite element analysis being used to determine wellhead seal parameters and its performance for subsea drilling service is also presented.