A Field-Based Method of Calibrating Inclinometers for Floating Drilling and Completion Operations with Applications of the Method to Reduce Differential Flex Joint Angles

摘要

Inclinometers in deepwater drilling and completion operations provide essential information for decisions involving millions of dollars. These devices are either manual ("bullseyes") or Electronic Riser Angle (ERA) systems that report angles of subsea equipment such as BOP's, flex joints, and wellheads. These readings, particularly from the manual devices, can be prone to error due to the difficulty of calibrating or "zeroing"the readings on a floating vessel. As a result, important operational decisions may be based on erroneous inclinometer readings. Incorrect decisions based on such readings could lead to a costly unnecessary stop in operations or a continuance of operations that may cause damage to subsea pressure containment equipment, with a resultant potential risk to the operability of this critical safety system.