深井小井眼钻井液技术

Research on drilling fluid technology for slim hole in deep wells and its application

为解决玉门青西油田深井开窗侧钻(或加深钻井)的钻井液防塌、抗高温、润滑、抑制和油层保护问题,经过对抑制剂、防塌剂、成膜剂的优选,应用“理想充填理论”对封堵粒子进行了优选复配,形成了阳离子—正电胶—有机(硅)醇抗高温深井钻井液体系,在玉门青西油田4口井侧钻、加深施工中应用了该技术。现场应用表明,井壁稳定,井径规则,井径扩大率小于8%,复杂损失率为0,岩心渗透率恢复值大于90%,产油量提高70%,很好地满足了深井小井眼钻井施工和油层保护的需要。

In order to solve the problems of hole stability, temperature resistance, lubrication, inhibition, and reservoir protection of drilling fluid used for deep windows sidetracking of Qingxi Oilfield in Yumen region, inhibitors, anti-sloughing agents, and film former agents are selected, as well as plugging particles are selected and combined based on the 'ideal packing theory' . As a result, the high temperature cation-positive gel-organsilicon alcohol drilling fluid system for deep wells is developed. The technology has been applied to the sidetracking and deepened construction of four wells in Qingxi Oilfield. Field application shows that the well bore is stable, the well diameter is regular, the well-hole enlargement is less that 8%, the complex loss rate is zero, the core permeability recovery value exceeds 90%, and the oil output increases by 70%. All this can fulfill the requirement of slim hole drilling for deep wells and reservoir protection.