重晶石和铁矿粉对套管/钻杆摩擦副摩擦磨损性能的影响

利用MG-200型高温高速摩擦磨损试验机对比考察了钻井液中所含的重晶石和铁矿粉对套管和钻杆试件摩擦学性能的影响，并采用扫描电子显微镜观察分析了磨损表面形貌，探讨了其磨损机理．结果表明，钻井液中的重晶石使得套管／钻杆磨损机理由严重塑性流动转变为磨粒磨损；而随着钻井液中铁矿粉含量的增大，磨损机理由磨粒磨损转变为粘着磨损和疲劳磨损；当铁矿粉含量较低时，采用较高的转速更有利于减小摩擦。

Influence of Iron Ore Powder and Barite on the Friction and Wear Behavior of Casing and Drill Pipe Pair

A series of friction and wear tests were performed on an MG-200 high temperature and high speed test rig to investigate the effect of barite and iron ore powder doped in the drilling mud on the friction and wear behavior of a casing/drill-pipe pair. Thus the friction and wear behaviors of the casing/drill-pipe pair sliding under the lubrication of the drilling muds containing various contents of barite and iron ore powder were evaluated in a ring-on-ring configuration. The worn surface morphologies of the casing and drill-pipe were observed on a scanning electron microscope. It was found that the barite doped in the drilling mud led to the change in the wear mechanism from severe plastic flow to abrasive wear and adhesion wear. The adhesion wear increasingly become severe with increasing iron ore powder content in the drilling mud, while the barite doped in the drilling mud was beneficial to decreasing the adhesion wear and plastic deformation of the casing/drill-pipe pair. Moreover, the iron ore powder had little effect on the friction coefficient at a relatively smaller sliding speed, while a larger friction coefficient was recorded at a larger sliding speed.