渤海油田井身结构优化及钻采技术研究与应用

Casing Program Optimization and Drilling and Production Technology Research and Application in Bohai Oilfield

为了节省渤海油田钻完井投资成本,降低低效益新建油田和调整井项目开发门槛,提高机械钻速,达到降本增效的目的,在满足勘探开发需求的前提下,综合现场实践效果、成本测算和对危废物处理的影响,优化缩小了渤海油田常用井身结构。同时,针对井眼和套管直径缩小后,受管柱内通径限制,在油井分采、水井分注、压裂充填防砂和小间隙环空固井等方面面临的技术难题,开展了配套工具研发。优化后的井身结构主要适用于井深3500 m以内的浅井和配产在400~500 m^3/d以内的油井。通过配套工具研发及优化,形成了一趟多层压裂充填工艺技术、Y型分采电泵管柱及工艺技术、空心集成分注技术、小间隙环空固井技术等配套钻采关键技术及工具。该系列技术已成功应用于渤海多个油田基本设计,完成1口井海试和4口开发井应用,钻井提效34.5%,提速降本效果显著。应用结果表明,该系列技术有效保障了油井低成本、安全、高效开发,在低效益的新建边际油田和调整井项目中具有广阔的应用前景。

To save the investment cost of drilling and completion in Bohai Oilfield,reduce the development threshold of low-efficiency new oilfields and adjustment well projects,increase the penetration rate,and achieve the purpose of reducing costs and increasing efficiency,on the premise of meeting the needs of exploration and development,comprehensively considering the field application results,cost estimation and impact on hazardous waste treatment,the casing program commonly used in Bohai Oilfield is optimized.In view of the technical difficulties faced by the separate layer production and injection,fracpack,sand control,and cementing in small annulus caused by the limited internal diameter of the casing after the size of the wellbore and casing has been reduced,supporting tools are development.The optimized casing program is mainly suitable for wells with the well depth of no more than 3500 m and the production rate of 400 to 500 m^3/d.Through the development and optimization of supporting tools,key drilling and production technologies and tools including one-trip multi-layer fracpack technology,Y-type separate layer production electric pump string and technology,hollow integrated separate layer injection technology,small annulus cementing technology are formed.The technologies have been successfully applied to the basic design of multiple oil fields in the Bohai Sea.One well sea trial and 4 development wells application have been completed with the increased drilling efficiency of 34.5%,presenting significant drilling speed improvement and cost reduction performance.Application results show that the technology effectively guarantees low-cost,safe and efficient development of oil wells,and has broad application prospects for low-efficiency new marginal oil fields and adjustment well projects.