Research On Operation Technology Of Ultra Deep Horizental Well In Yuanba Field

Because of the special geological background and the complicated engineering condition,Yuanba Gas Field become the worst gas field with most severe condition in China.The main problems for borehole operation are deep depth,marine facies and long horizontal wellbore.Therefore,according to the basic characteristics of yuanba region,in this paper,the problems of operation are analyzed and corresponding technical countermeasures are put forward for the three aspects:borehole operation,acid reconstruction and testing for production.First of all,combining geological literature of Yuanba ultra deep horizental well,analyze the difficulties and risks,refine the operation technology requirements and optimize operation parameters.Then corresponding technical measures and coping strategy for complex conditions are worked out.Last,a set of operation technology has been formed.So the following results have been achieved:(1)Completion risk identification model is established.The risk prediction was carried out on the well section with big dog-leg angle,according to the of curvature,borehole diameter and tool size.As a result,reducing the operation risks are reduced,the efficiencies of the completion and operation are improved.(2)The positions obstructed easily are counted and the reasons why the blocking happens are analyzed.So well gauge tools and completion tools can be put in well-bottom.(3)Because the jamming of a drilling tool is difficult to be solved,the reasons of jamming are analyed and the positions of jamming are pointed out.(4)Using multi-stage alternate temporary plugging acid pressure technology,optimize the temporary blocking agent so that the acid can be distributed evenly.