侧钻绕障技术在干热岩HDR-1井中的应用

Application of sidetracking to obstacle bypassing in hot dry rock Well HDR-1

东南沿海深部干热岩科学钻探HDR-1井在3000 m以深发生卡钻事故,经过多种方法处理后,井内仍留有100多米“落鱼”。由于继续套铣打捞井内“落鱼”难度大、风险高、周期长,经多方论证,决定采用侧钻绕障技术绕过事故井段。经过对套管斜向器侧钻、裸眼水泥塞侧钻和裸眼斜向器侧钻3种方案进行对比,最终采用裸眼水泥塞侧钻方案。此次侧钻绕障的成功应用,在国内干热岩施工中尚属首次,克服了大深度、大直径、高温度、高硬度等技术难题,综合运用了随钻测量、复合动力钻进工艺、抗高温钻井液等先进技术,为我国干热岩科学钻探与深部地热资源勘探提供了新的技术支撑。

A sticking incident happened in HDR-1 well at a depth of 3000m in hot dry rock.After various treatments,over 100m long“lost fish”still remained downhole.With the casing‑milling method to continue to deal with the fish,it may lead to great difficulty,high risk and long period.After trade‑offs of various methods,it is decided to adopt the method of sidetracking to bypass the incident section.Through the comparison of three plans of sidetracking with the deflector inside casing,sidetracking from the open hole cement plug and sidetracking with the open hole deflector,sidetracking from the open hole cement plug was finally adopted.The successful application of sidetracking around the barrier is the first time in hot dry rock drilling in China,which has overcome the technical difficulties of large depth,large diameter,high temperature and high hardness,and applied advanced technology,such as measurement while drilling,complex power drilling technology,high temperature resistant mud,providing new technical support for hot dry rock scientific drilling and deep geothermal resource exploration in China.