OPERATING GUIDELINES FOR EMERGENCY DISCONNECT OF DEEPWATER DRILLING RISERS

摘要

For deep water applications, drilling risers are frequently deployed from dynamically positioned (DP) floating vessels. A DP vessel can lose its ability to hold position. Under such conditions, there must be some means to disconnect the riser safely and quickly to avoid damage to the riser, vessel, blow out preventor (BOP) stack, or wellhead. A companion paper presented at this conference (Stahl, 2000) discusses riser disconnect analysis. The present paper shows how such analysis was applied to a drilling operation from a DP drillship located in a Gulf of Mexico field in 6200 ft (1890 m) of water. This work determined tension limits under a wide range of mud weights and heave amplitudes for both planned and emergency disconnect. Although tensioner systems and recoil control systems vary from one vessel to another, the approach and criteria used here can be adapted to a wide range of vessels.