Effect Evaluation And Decision-making Of Well Completion In Shengli Oil Field

Well completion technique can directly affect oil well production and economic benefits of oilfield development.Nowadays,oilfields select well completion methods qualitatively and experienced,based on the reservoir types,properties of crude oil,oil lifting,and requirements of well work.Ignored the requirements of technology and economy,to form well completion technical effect assessment and the comprehensive indexes of decision,especially ignored the influence of different factors on comprehensive assessment indexes,which influence evaluation and decision.Therefore,setting up a scientific well completion technology of effect evaluation indexes and evaluation standards,and using scientific decision technology are essential for it.For these problems,the thesis screened and studied technical and economic indexes in eight evaluation of efficacy of the well completion technology.Technical indexes include initial mean effective production strength,recovery of well controlled reserve,skin factor and production decline rate,and yield rate.Economic indexes include unit of single well completion process cost,net present value and payback period.The thesis analyzed the influence factors and influence rule of various indexes,use calculating fuzzy comprehensive evaluation for comprehensive evaluation and decision of well completion technology,to calculate the comprehensive index for evaluation and decision of well completion technology,and edited the relevant software.Chen 25 block,Chen 319 block,Chen 371 block,Chen 373 block,and the Western of Chengdong district are the five objects of study.The thesis evaluated 120 horizontal wells.The rate of the standard “excellent,good,middle,general,bad” is 21%,21%,21%,19%,18%.That indicated level for selection of well completion technology need to be improved.Compiled software for evaluation and decision of well completion process,the compliance rate is 88%,the situation of accuracy and inspection for the software,and the situation of calculation accuracy analysis,indicated a model for calculating the fuzzy comprehensive evaluation developed calculation software can provide scientific and effective decision support for optimization of well completion methods in oilfield.