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Failure analysis of the tripping operation and its impact on well control

conference contribution
posted on 2023-05-23, 10:01 authored by Abimbola, M, Khan, F, Vikrambhai GaraniyaVikrambhai Garaniya, Butt, S
As the cost of drilling and completion of offshore well is soaring, efforts are required for better well planning. Safety is to be given the highest priority over all other aspects of well planning. Among different element of drilling, well control is one of the most critical components for the safety of the operation, employees and the environment. Primary well control is ensured by keeping the hydrostatic pressure of the mud above the pore pressure across an open hole section. A loss of well control implies an influx of formation fluid into the wellbore which can culminate to a blowout if uncontrollable. Among the factors that contribute to a blowout are: stuck pipe, casing failure, swabbing, cementing, equipment failure and drilling into other well. Swabbing often occurs during tripping out of an open hole. In this study, investigations of the effects of tripping operation on primary well control are conducted. Failure scenarios of tripping operations in conventional overbalanced drilling and managed pressure drilling are studied using fault tree analysis. These scenarios are subsequently mapped into Bayesian Networks to overcome fault tree modelling limitations such s dependability assessment and common cause failure. The analysis of the BN models identified RCD failure, BHP reduction due to insufficient mud density and lost circulation, DAPC integrated control system, DAPC choke manifold, DAPC back pressure pump, and human error as critical elements in the loss of well control through tripping out operation.


Publication title

ASME 2015 34th International Conference on Ocean, Offshore and Arctic Engineering






Australian Maritime College


American Society of Mechanical Engineers

Place of publication


Event title

The 34th International Conference on Ocean, Offshore and Artic Engineering

Event Venue

St. Johns, Newfoundland, Canada

Date of Event (Start Date)


Date of Event (End Date)


Rights statement

Copyright 2015 ASME

Repository Status

  • Restricted

Socio-economic Objectives

Natural hazards not elsewhere classified

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