旅大某油田储层岩石胶结疏松、孔隙发育，且黏度、密度、胶质沥青质和凝固点高，钻井过程中由于钻开液的滤失导致储层水敏损害、不配伍等储层伤害。为改善以上问题并降低施工成本，在现有钻开液体系基础上，通过优化防膨剂、降滤失剂、流型调节剂等添加剂的加量制得适合旅大某特稠油的新型无固相钻开液体系，研究了钻开液的配伍性、抑制性、降解性和储层保护性。结果表明，在现有钻开液中加入有机防膨剂 CFP、1%降黏剂、1.0%~ 1.5%降滤失剂改性淀粉、0.3%~ 0.4%流型调节剂改性胍胶制得的钻开液体系防膨性较好，与地层流体的配伍性良好，抑制钻屑分散能力较强，无沉淀、无乳化堵塞损害，260℃高温降解后对岩心的渗透率恢复值大于85%，具有良好的储层保护效果。该钻开液体系降低了作业成本，适用于特稠油油田的热采开发。表6参12
Reservoir of Lvda oilfield had characteristics of loose cementation，pore abundance，high viscosity，high density，high content of gum and asphaltene，and high freeze point. Reservoir damage，such as water sensitivity and incompatibility，would occur because of drilling fluid loss during drilling operation. In order to improve above problems and reduce construction costs，a new clay free drilling fluid system suitable for Lvda extra-heavy oil reservoir was prepared by optimizing the dosage of inhibitor，fluid loss agent and flow pattern regulator，on the basis of the existing drilling fluid system. Drilling fluid properties of compatibility，inhibitive ability，degradability and reservoir protection were studied. The results showed that the new drilling fluid system prepared by adding inhibitor CFP，1% viscosity reducer，1.0% —1.5% filtrate reducer modified starch and 0.3% —0.4% flow pattern regulator modified guar into the current drilling fluid，had good anti-swelling，good compatibility with formation，great ability to inhibit drilling cuttings dispersion without sediment and emulsion block. The core permeability recovery value exceeded 85% after degradation at 260℃，showing favorable reservoir protection of new drilling fluid system. This drilling fluid system reduced operating cost and adapted to thermal recovery in extra-heavy oilfield.