轮古40C井套管开窗侧钻小井眼定向钻井技术

在老井改造措施中,采用套管开窗侧钻比较普遍,而在侧钻过程中经常会遇到不同的地层压力系数,必须增加一层套管,这样就得用更小尺寸的钻头钻进,施工难度也随之加大。轮古40C井所遇到的正是此种情况。为了预防窗口小影响下步施工,在塔里木油田深井中,套管开窗侧钻一般采用锻铣套管开窗,为减少施工工序,该井使用了斜向器开窗,并在?152.4 mm井眼顺利下入了?127 mm尾管并固井,然后用?104.8 mm钻头钻达设计井深。通过该井的成功探索,说明使用一次性斜向器开窗侧钻是可行的;钻?104.8 mm小井眼时,防止发生钻具事故是关键,如果钻具脱落,首选公锥进行打捞。

Sidetrack Drilling and Slim Hole Directional Drilling Technique in Lungu40C Well

Among the reconstruct measurements of aged wells, sidetrack drilling is very prevalent, while during the drilling, it always meets different formation pressure coefficient, and one more layer of casing is applied, then the smaller bits may be put in use, the drilling operation difficulty increases. The Well of Lungu40C has met such an occasion. Sidetrack drilling generally uses milled window in casing because of worry about the size of the window will affect the next operation in the deep well of Tarim oil field. In order to save the procedures and the time, whipstock was put in use in this well. Having set the ?127 mm liner in ?152.4 mm hole and cemented successfully, then drilled to the designed well depth with the ?104.8 mm bit. Through the exploration of this well explain that the use of one time whipstock milled window in casing is feasible. Prevention of the occurrence of drilling pipe and tools accident is the key when drilling ?104.8 mm slim hole, and when the drilling pipe and tools fall off, pin tap might be the first selection of fishing tools.