Shell Expro ("Shell U.K. Exploration & Production", operators in the U.K. North Sea on behalf of Shell and Esso) have recently reviewed equipment requirements for the control of kicks incurred while drilling high pressure wells. Based on a "worst case" of a well bore full of gas, deriving from a reservoir pressure of some 14,000 psi [97 MPa], analysis of existing well control equipment standards has indicated a requirement for enhancements. New equipment standards have been developed and implemented, which will in all circumstances permit the well to be controlled, and the influx to be safely circulated out. These new standards principally apply to equipment which was already installed, though this equipment has been modified where necessary. These new standards mainly affect the BOP's elastomers, the choke manifold and the casing design. In some instances, control procedures have also been modified to take into account those equipment limitations that cannot readily be overcome. The main procedure change is the establishment of a maximum allowable kill rate which is governed by the capacity of the gas handling equipment on surface. These revised equipment standards and procedures will enable to control a well kick without danger to personnel or to the installation and should engender the confidence of the rig personnel.

You can access this article if you purchase or spend a download.