20 KSI BOP STACK

OBJECTIVE:

To design a complete 18.75” – 20 KSI BOP Stack from a clean sheet of paper. Frequently designs are complicated by needing to deal with the historic sequence of design.  As a result means this newly designed components must deal with the limitations of previously designed components.  To start over allows a designer to question the design characteristics of every component.  As a result this gives opportunities for fresh ideas.

BACKGROUND:

This work on a new BOP stack has been based on more than 60 years experience with more than 150 U.S. patents issued, including patents on most parts of a subsea blowout preventer stack.

INNOVATIONS:

 

20 KSI BOP STACK:

1. A 20 K.S.I. blowout preventer stack as short and light as a conventional 15 K.S.I. blowout preventer stack.
2. The option for all electric actuators is kept open, although not a part of this project.
3. Substantially changed structure which helps clean up access to all components.

RAM BLOWOUT PREVENTER

1. Bidirectional rams
2. Rams with controlled pressure amplification
3. Shear rams with face seals w/o bending the pipe
4. Elimination of bonnet bolting

ANNULAR BOP:

1. 18.75” annular capable of 20 K.S.I.
2. Bidirectional annular BOP
3. Shared differential between two 10 K.S.I. annulars

MISCELLANEOUS CONCEPTS RELATING TO:

1. Wellhead Connector including automatic gasket retention
2. Choke and Kill Connector which engage automatically without secondary operations.
3. Accumulators with 150 gallon working capacity.  Reduced area requirements and workable at all depths.
4. Control systems including simplified connections between the LMRP and Lower BOP Stack and improved cable handling.
5. Riser Connectors which allow rapid makeup and testing and as a result allows faster deployment.
6. ROV interfacing, including 100% redundancy in controls by an ROV and as a result better overall safety.
7. Manufacturing processes which aid in the reduction of the overall 20 KSI BOP stack size
8. Continuous current measurement below rig at any depth and therefore better operating information.