M油田盐膏层段分级箍选型优化及现场应用

Selection Optimization and Field Application of Stage Collar in Salt Paste Layer of M Oilf ield

M油田盐膏层段存在埋深较深、岩性复杂、厚度大、压力窗口窄等诸多挑战,根据当地政府法规要求,盐膏层固井需返至井口,为了降低地层漏失风险、提高固井质量,需要采用双级固井作业。分级箍作为双级固井必须使用的工具,目前主要有机械型、液压型和液压机械双作用型。文章通过分析M油田作业情况,通过比较机械型、液压型,以及液压机械双作用型三种分级箍的优缺点,最终根据现场的油田情况,优选出了液压机械双作用型分级箍。通过后续在新的钻井应用这种分级箍,结果表明,该种液压机械双作用型分级箍能保证及时打开和关得严,为固井质量的提高提供了必要的保证,也为该区块的其他井进行双级固井作业分级箍选型提供了借鉴。

M oilf ield has many challenges such as deep burial depth,complex lithology,large thickness,narrow pressure window,etc.According to the regulations of the local government,the cementing in the salt-paste layer needs to be returned to the wellhead.In order to reduce the risk of formation loss and improve the quality of cementing,two-stage cementing operation is needed.As a necessary tool for two-stage cementing,there are mainly mechanical type,hydraulic type and hydraulic mechanical double acting type at present.By analyzing the operation situation of M oilf ield,and comparing the advantages and disadvantages of mechanical type,hydraulic type and hydraulic mechanical double-acting stage collar,this paper f inally selects the hydraulic mechanical double-acting stage collar according to the f ield situation.Through the subsequent application of the stage collar in new Wells,the results show that this kind of hydraulic and mechanical double-acting stage collar can ensure the timely opening and closing of the tightly,which provides necessary guarantee for the improvement of cementing quality,and also provides a guiding signif icance for the selection of stage collar for two-stage cementing operation in other wells in this area.