不同加重材料对N80钢表面磨损的实验研究

对比考察了超微重晶石、普通重晶石、四氧化三锰与铁矿粉加重的高密度钻井液对N80金属表面磨损的影响;并利用扫描电子显微镜观察了磨损试件表面形貌;且利用表面粗糙度仪测试了表面粗糙度,探讨了不同加重材料的磨损机理。实验结果表明:超微重晶石对N80钢磨损量是普通重晶石的57.8%,四氧化三锰对N80钢磨损量是铁矿粉的43.8%。在高固相条件下,普通重晶石、超微重晶石、铁矿粉和四氧化三锰对金属表面的磨损主要表现为磨粒磨损、犁削作用、刨削作用和表面疲劳磨损。四氧化三锰和超微重晶石可以充填吸附在金属表面的凹凸处,可显著降低对N80钢表面的磨损程度,四氧化三锰可使得N80钢表面粗糙度降低到铁矿粉的50%。

Influence of Different Weighting Materials on the Wear of N80 Metal Surface

Influence of high-density drilling fluid weighted with conventional barite, micronized barite, iron ore powder and manganese tetroxide on the wear behavior of N80 metal surface was investigated. The worn surface morphologies and roughness of the N80 metal was observed and tested respectively by scanning electron microscope and surface roughness meter tester. The wear mechanisms of different weighting materials were also discussed. It was found that the erosion rate of N80 steel worn by micronized barite is 57.8% of it worn by conventional barite, and the erosion rate of N80 steel worn by manganese tetroxide is 43.8% of it worn by iron ore powder. The wear mechanism of conventional barite, micronized barite, iron ore powder and manganese tetroxide on the metal surface is abrasive wear, plowing, planning action and surface fatigue wear, under conditions of high density drilling fluid. Manganese tetroxide and micronized barite can significantly reduce the wear on the metal surface because of filling and adsorption on the concave and convex of the metal surface, especially the roughness of N80 steel surface worn by manganese tetroxide can be reduced to 50% of the iron ore powder.