龙凤山气田抗高温防塌钻井液研究与应用

Research and Application of High Temperature Resistance and Anti-sloughing Drilling Fluid in Longfengshan Gas Field

龙凤山气田青山口组、泉头组和登娄库组地层岩石胶结能力差,在钻井过程中经常发生垮塌、卡钻、井漏等复杂情况。针对该区块的地质特性和钻井要求,研制了一种以SMNA-1为封堵防塌剂的抗高温防塌钻井液,并进行了性能评价。实验结果表明,该钻井液体系具有抗温能力强、流变性能良好、滤失量低和防塌效果显著的特点。在北8井的现场应用中,钻井液性能稳定,无垮塌现象,起下钻、电测和下套管作业无遇阻,很好地满足了现场钻井施工的需要。

In Longfengshan gas field,the cementation ability of rock is poor in the Qingshankou Formation,Quantou Formation and Denglouku Formation.Sloughing hole,pipe-stuck and lost circulation are always encountered in drilling operation.The high temperature resistance and anti-sloughing drilling fluid was developed by using SMNA-1 as anti-sloughing agent in accordance with geological characteristics and drilling requirements,and the properties were evaluated.Experimental results showed that this drilling fluid system had the advantages of high temperature resistance,good rheological property,low filter loss and significant anti-sloughing performance.In the field application on Bei 8,the drilling fluid showed steady performance,no sloughing hole occurred,and no obstruction were encountered during tripping in and out,electrical logging and casing installation,thereby the requirements of drilling operation were satisfied.