苏里格南部气田大斜度井钻井技术

Drilling technologies used for the highly deviated wells in Southern Sulige Gasfield

苏里格南部区块大斜度井平均完钻井深3 900 m,平均水平位移1 200 m,施工过程中存在井深、位移大、轨迹控制难度大、地层可钻性差等技术难题,严重制约钻井速度。为此,从优化剖面设计、轨迹控制、钻具组合及钻头、螺杆选配等技术出发,形成了一套苏里格南部气田大斜度井高效钻井关键技术:"直-增-稳-微降"剖面、"两趟钻"轨迹、稳斜能力强的"四合一"钻具组合、适合该区块快速钻井的钻头及螺杆。通过关键技术的应用,2017年平均钻井周期缩短至11.95 d,较2016年平均钻进周期缩短2.56 d,提速17.64%,提速效果显著。

The extended reach wells in Southern Sulige Block have average total depth of 3 900 m and average horizontal displacement of 1 200 m.Their rate of penetration(ROP)is restricted seriously due to the technical difficulties in the process of construction,e.g.deep well,large displacement,difficult trajectory control,and poor formation drillability.In regard of this,a series of key drilling technologies for the efficient drilling of extended reach wells in Southern Sulige Gasfield were developed from the aspects of profile design optimization,trajectory control,bottom hole assembly(BHA)and bit and screw rod selection.They include “vertical-buildup-angle holding-slight drop” profile,“two-trip drilling” trajectory,“four-in-one” BHA with strong angle holding capacity,and bit and screw rod suitable for fast drilling in this block.Owing to the application of these key technologies,the average drilling cycle in 2017 is shortened to 11.95 d,which is 2.56 d shorter than that in 2016,and the ROP is increased by 17.64%,presenting remarkable ROP improvement effect.