塔河油田托普台3区志留系钻井液难点及对策

塔河油田托普台3区志留系柯坪塔格组砂泥岩互层发育，层厚一般为340～420 m，埋深一般在井深5 570～6 200 m，且呈现自北向南逐渐增厚、埋深逐渐加深的态势。通过分析柯坪塔格组岩性、井壁失稳及井漏发生的原因，结合室内评价抑制剂、防塌封堵剂，形成了适合该区块的钾胺基防塌钻井液体系配方；制定了详细的柯坪塔格组防塌防漏技术措施、工程预防措施，通过物理防塌与化学防塌相结合，强化分段静堵和随钻封堵技术，高软化点乳化沥青与刚性粒子组合防塌封堵；工程上通过控制起下钻速度、起下钻分段顶通循环等手段。该钻井液体系在TP346X井应用取得较好的效果，柯坪塔格组井径扩大率为7.45%，掉块垮塌明显减少，未出现漏失等复杂情况。

Technical challenges and solutions of drilling fluid techniques in Silurian in Tuoputai 3 block of Tahe oilfield

Sandstones and mudstones interbedded in the Silurian Kepingtag Formation in the Tuoputai 3 block of Tahe oilfield, about 340-420 m thick for each layer and generally buried at a well depth of 5 570-6 200 m. The interlayer thickness and burial depth gradually increased from north to south. By analyzing the lithology of the Kepingtag Formation and the causes for wellbore instability and well leakage, combining with the laboratory evaluations of inhibitors and anti-collapse plugging agents, we proposed a formula for potassium amine anti-collapse drilling fluid, which is suitable for the Tuoputai 3 block. Some detailed measures to solve collapse and leakage were put forward, combining physical anti-collapse methods with chemical ones. Segmental static plugging and drilling plugging were focused on. A combination of high softening point emulsified asphalt and rigid particle was applied to solve collapse. Velocity was controlled and drilling fluid was circulated when drilling up and down. This drilling fluid system achieved good effects in well TP346X. The drilling diameter of the Kepingtag Formation was improved by 7.45%. Collapse was significantly reduced and there was no leakage or other complex situations.