哈得4油田双台阶深水平井钻井液技术

Drilling fluid technology for two-step profile deep horizontal wells in Hade 4th Oilfield

塔里木哈得 4油田油藏埋深在 5 0 0 0m以下 ,油藏厚度薄 ,约 0 .3～ 2 .0m ,适合钻双台阶水平井准确开发不同的油层。该油田地质情况复杂 ,易造成泥包钻头、卡钻、井漏、井塌等井下复杂情况。开发了适用于超薄油藏的双台阶深水平井的聚合醇 正电胶 聚磺混油钻井液。现场应用表明 ,该钻井液抑制性强 ,润滑防塌性能好 ,井底摩阻一般在 10～ 2 0t之间 ;井眼净化能力强 ,有效防止了岩屑床的形成和泥包钻头 ;维护处理简便 ,有利于环保。

Oil reservoir of Hade 4th oilfield lies in depth more than 5000 m, with the productive layer as thin as 0.3～2.0 m. It is suitable to drill two-step profile horizontal well to accurately explore different formations. For complex geologic conditions, bit balling, drill pipe sticking, wall sloughing and lost circulation are easily to occur. The polycol/MSF/Polysulfonate/Oil drilling fluid system suitable for two-step profile horizontal wells were developed to explore superthin oil reservoir. Field using showed that the fluid has strong inhibitive ability, good lubricating property to prevent wall collapse (the friction resistant down hole is 10～20 t), with no oroblem aooeared in continues operations, it performed effective hole cleaning,and cutting-bed formation and bit balling were avoided. Not only the fluid maintenance is convenient, its environmental acceptance is its additional advantage.