高钙盐钻井液体系的研究与应用

针对塔河油田第三系地层易缩径、阻卡，三叠系、石炭系地层井壁易坍塌扩径的特点，优选了高钙盐钻井液体系。现场应用表明，该钻井液体系具有极强的抑制性和防塌能力。可有效解决浅层泥岩吸水缩径、砂岩段厚泥饼缩径和深部(三叠系、石炭系)泥页岩剥蚀掉块垮塌等问题，试验井三叠系、石炭系平均井径扩大率小于6％，完井电测及下套管固井等作业顺利。且该体系在同样地层钻进中的密度低于常规钻井液体系，有利于油气层保护。

The Study and Applications of High Lime Mud

Tight hole and pipe sticking are likely to happen while drilling through the Tertiary system in the Tahe Oilfield. The high lime drilling fluid is optimized for penetrating sloughing formations of the Triassic system and the Carboniferous system. Field applications of such mud show that it performs high inhibitive and an-ti-caving capacities. The drilling fluid system can effectively prevent shallow shale from hydration and tight hole, prevent from making thick drilling fluid filter in sandstone formations, solve shale caving in deep shale such as the Tertiary system and the Carboniferous system. Hole enlargement through the Tertiary system and the Carboniferous system in test wells are less than 6%, therefore, got a successful completion logging and running casing strings. In addition, the drilling fluid density is less than one of normal drilling fluids while drilling the same formations, which is in favor of protecting reservoirs.