Research Of Safety Barrier Model Based On Deepwater Drilling Well Control

Deepwater drilling is a challenging project with high cost and high risk.Although the probability of deepwater drilling blowout is not high,more serious is that it would not only cause the waste of oil and gas resources,but also cause well crash and marine ecological environment destruction.Well control is a barrier system for preventing kick from becoming blowout,the success or failure of well control concerns whether blowout would appear.Therefore,research on risk assessment method of deep-water drilling well control,in particular,quantitative risk assessment(QRA)method,will help to identify risk causes,clear level of danger,and take measures to reduce risk in advance to avoid the happening of the blowout.Foreign Marine oil and gas development started relatively early,deepwater oil and gas development technology is relatively mature,also at present abroad has established a relatively perfect deep water well control well safety barrier system,and the corresponding safety barrier system analysis and evaluation method.Relative to foreign and domestic Marine oil and gas development started relatively late,the development of deepwater oil and gas is at the start-up stage,therefore,through the security barrier model analysis,determine the risk point with high risk of the failure mode or safety barrier,and targeted the establishment of corresponding security barrier,can reduce the possibility of accident,limit the degree of danger of accident,reduce accident consequences,achieve smooth safe deepwater oil and gas development processOpen cycle is presented in this paper fuzzy event tree phase of deep water well control technology barrier,the fuzzy probability of calculated through expert scoring,into the bayesian model is set up to calculate the deep water well control of the main failure mode for secondary technical barrier MWD and DKD device failure.Closed cycle stage wellbore is established for deep water well control technology barrier of drill pipe when the accident tree,is transformed into dynamic bayesian model,to the prior probability,and calculate the probabilistic following,draw a closed cycle stages within thewellbore is the drill pipe when the deepwater secondary well control technology barrier failure probability curve along with the change of time and its main failure mode for wellhead connector failure,lower riser assembly and technical barrier to detect failure.This paper established the dynamic bayesian network model of personnel and organizational barriers,calculated the personnel/organizational barrier changing with the time of the failure probability,and through to the foreign Marine oil and gas development started relatively early,deepwater oil and gas development technology is relatively mature,also at present abroad has established a relatively perfect deep water well control well safety barrier system,and the corresponding safety barrier system analysis and evaluation method.Relative to foreign and domestic Marine oil and gas development started relatively late,the development of deepwater oil and gas is at the start-up stage,therefore,through the security barrier model analysis,determine the risk point with high risk of the failure mode or safety barrier,and targeted the establishment of corresponding security barrier,can reduce the possibility of accident,limit the degree of danger of accident,reduce accident consequences,achieve smooth safe deepwater oil and gas development processAccording to the results of the calculation and analysis,corresponding management measures are put forward,and some because of insufficient data to calculate the other risk factors and failure modes of response.Prior probability and posterior probability calculation,it is concluded that the failure mode of personnel/organizational barriers mainly for supervision and knowledge of team management skills and shift handover,platform management rules and regulations is to personnel/organizational barriers.