一种高性能环保型钻井液润滑剂的研究与应用

Evaluation and Application of the High Performance Environmentally Friendly Drilling Fluid Lubricant HPRH

随着钻井地质条件的日益苛刻,长水平段高摩阻扭矩、深井高温等复杂环境对钻井液润滑剂的润滑性、抗温能力及环保性等提出了较高的技术要求,现有的钻井液润滑剂通常难以同时满足上述需求。笔者通过对环保基础油、润滑改性剂的优选及制备条件优化,研制出了一种高性能环保型钻井液润滑剂HPRH。室内评价结果表明,当其加量为0.5%时,HPRH在淡水基浆及4%NaCl盐水浆中的润滑系数降低率分别达到93.75%及80.64%;可抗温160℃,起泡率低,且无荧光;室内销-盘式摩擦磨损试验结果表明,HPRH的抗磨耐磨效果显著,润滑持效性好,长磨60 min后盘的体积磨损量仅为6.92×10^(-13) mm^3/(N·m)。HPRH在塔里木油田LN区块2口评价井水平井段进行了现场试验,应用结果表明,与现场常用复合润滑剂相比,HPRH表现出显著的高性能特点,润滑持效性良好,用量减少了50%以上,且有效避免了托压、卡钻等井下复杂事故,起到了显著的降本增效效果。

With drilling geological conditions becoming increasingly rigorous,high drag and torque encountered in long horizontal drilling and high temperature deep well drilling have imposed higher requirements on the lubricity,thermal stability and toxicity of lubricants.These requirements are apparently not be able to be satisfied with lubricants presently in use.Laboratory experiments have been conducted in the selection of base oil,optimization of lubricity enhancers and optimization of conditions for the development of a high performance environmentally friendly lubricant,HPRH.In laboratory evaluation test,0.5%(mass ratio)HPRH in fresh water base drilling fluid reduced the friction coefficient of mud by 93.75%,while in 4%NaCl saltwater base drilling fluid,this percentage reduction in friction coefficient was more than 80%.HPRH functions properly at 160℃,has low foaming and is free of fluorescence.Laboratory pin-disc friction and wear test results show that HPRH has remarkable anti-wear and wear-resisting property,and good lubricity persistence.After being wore for 60 min,the volumetric abraded quantity of the disc was only 6.92×10-13 mm3/(N?m).Field application of HPRH on two appraisal wells drilled in Block LN in Tarim Basin showed that,compared with compound lubricants used in field operations,HPRH has better lubricity persistence,and the amount of HPRH was reduced by at least 50%.The use of HPRH effectively avoided downhole troubles such as being unable to exert pressure on bit and pipe sticking etc.,greatly reducing the drilling cost and enhancing the operational efficiency.