钻井液类型对套管磨损行为的影响

Effect of Drilling Fluid Type on Wear Behavior of Casing

为研究钻井液类型对套管摩擦磨损行为的影响,本研究分别用N80钢材套管和G105钢材钻杆材料加工制作销盘和销钉,分别以水基钻井液和油基钻井液为润滑介质,在MZM-500型销-盘式摩擦磨损实验机上开展了套管钻杆摩擦磨损实验,得到不同润滑介质下的销盘磨损率、摩擦系数以及钻井液温度变化数据,并对实验后的销盘进行三维形貌测试,表面形貌测试(SEM)和表面磨损产物XRD分析。结果表明:以水基钻井液为润滑介质的销盘磨损率大约为0.00015mm 3·N-1·m-1,以油基钻井液为润滑介质的销盘磨损率大约为0.00008mm 3·N-1·m-1;水基钻井液中的销盘摩擦系数大约为0.28,而油基钻井液中的销盘摩擦系数大约为0.15;两种润滑介质实验后销盘表面磨损产物都含有Fe 2O 3,FeCl 2,FeC 3,CaCO 3,MgCO 3,但含量不同,对比油基钻井液,销盘在水基钻井液中实验后表面磨损产物中FeCl 2含量较多,Fe 2O 3含量较少。经分析,套管在钻井液中的磨损机理为磨粒磨损和腐蚀磨损,油基钻井液较水基钻井液具有更好的润滑性能。

Effect of drilling fluid type on wear behavior of casing were studied in the present work.N80 carbon steel and G105 carbon steel were used to process disk and dowel.Water-based drilling fluid and oil-based drilling fluid are used as lubricating media,respectively,friction and wear experiments of casing and drill pipe were carried on MZM-500 pin-disc friction and wear test machine.The wear rate,friction coefficient,change of drilling fluid temperature,3-D surface features,surface profile of the wear product films and composition of the wear product under different drilling fluid were analyzed.The results showed that the wear rate of the disk in water-based drilling fluid is about 0.00015mm 3·N-1·m-1,and that of oil-based drilling fluid is about 0.00008mm 3·N-1·m-1.The friction coefficient of the disk in the water-based drilling fluid is about 0.28,while the friction coefficient of the disk in the oil-based drilling fluid is about 0.15.The wear products of the disk in both lubrication mediums contained Fe 2O 3,FeCl 2,FeC 3,CaCO 3,MgCO 3,with different content.Compared with oil-based drilling fluid,the surface product of disk in water-based drilling fluid had more FeCl 2 and less Fe 2O 3.The wear mechanism of casing in the two drilling fluids are abrasive wear and corrosion wear.Oil-based drilling fluid has better lubrication performance than water-based drilling fluid.