Multi-Stage Frac Sleeves Completion Risk Matrix-A Quantitative Approachto Minimize Stuck Incidents while Deploying Completions Across HorizontalSlim-Holes

摘要

Drilling and completing wells for hydrocarbon production comprise the major cost of well operations.Slim-hole drilling can significantly reduce drilling costs,making low producing reservoirs economically viable.However,a number of challenges are associated with slim-hole wells.A major challenge encountered whiledeploying lower completions in long horizontal slim-hole wells is stuck pipe,as the wellbore diameter isless than six inches,allowing restricted clearance between the wellbore and completion equipment.Stuckpipe incidents can cause significant non-productive time(NPT),additional high costs,and the possibilityof compromising the well objective.Stuck pipe incidents may require sidetrack operations in the worst cases,which may considerably changethe planned well design and delay the overall project,along with increasing costs.Drilling in the minimumstress direction with heavy mud weight and high overbalance pressure adds to the challenge in deployingcompletions in HPHT slim-hole wells.While deploying the lower completions in slim-hole wells,manyfactors come into play and each factor has a critical role in the success of the operation.After conducting a detailed study on several HPHT slim-hole gas wells in Middle-East region,a riskmatrix was developed for a specific well-bore diameter,by identifying some common variables.Based onpotential chance of occurrence,a certain value was assigned to each variable.The risk mitigation plans aredriven by the risk matrix variables.Using this risk matrix,the occurrences of stuck pipe incidents in criticalHPHT slim-hole wells that initially tend to have high chances of stuck pipe were significantly reduced.The risk matrix presented in this paper successfully mitigated stuck pipe incidents from occurring and hassaved millions of dollars in associated costs.The matrix played a key role in operator's drilling operationsand was adapted in operations as an important tool to evaluate final wellbore conditions prior to selection ofthe optimum completion type.This paper presents a highly effective risk matrix that significantly minimizesstuck pipe incidents during drilling/completion operations of slim-hole gas wells.