宁东油田NP7小井眼水平井钻井液技术

Drilling Fluid Technology for Slim-hole Horizontal Well NP7 in Ningdong Oilfield

针对宁东26井和NP3井发生的复杂情况,结合NP7井钻井液技术难点,在不同井段采用不同的钻井液体系及现场维护处理措施。实钻证明,NP7井使用的钾铵基聚合物钻井液、钾铵基沥青复合防塌钻井液和低固相钾铵基硅醇钻井完井液体系,解决了该区块上部志丹群软泥岩地层易水化分散造浆,易形成厚泥饼阻卡;中部安定、直罗组大段泥页岩地层易膨胀分散、剥落掉块;下部延安组硬脆性泥页岩、煤层易垮塌、起下钻困难、岩屑床阻卡等技术难题,达到了优质、安全、快速钻井和保护油气层的目的。3.6 d完成水平进尺482 m,平均机械钻速达到7.59 m/h,创造了宁东26井区小井眼水平段快速钻进新纪录。

Some problems are encountered in wells of Ningdong 26 and NP3,based on the analysis of that,in well NP3,different drilling fluid systems and treating measures are applied in different intervals.The application in well NP7 shows that the potassium amine polymer drilling fluid system,potassium amine asphalt anti-sloughing drilling fluid system and low-solid potassium amine silanol drill-in fluid system can solve these problems,such as pipe-stuck in upper Zhidan group caused by hydrated soft shale forming thick mud cake,sloughing in the middle Anding and Zhiluo groups caused by thick shale formation,and hard tripping in the lowerYan’an group caused by brittle shale and coal formation forming cuttings bed.It is spent 3.6 days to finish horizontal penetration of 482 m,and the ROP reaches to 7.59 m/h,which has created new record of drilling in slim-hole horizontal section in block of Ningdong26.