负扭矩 meaning in English

negative torque
negative torsional moment

The result of simulation of model 8 ? 1 / 2 ? xhp2s bit shows that , the torque on the bit changes randomly , and the degree of the change increases with the increase of the weight on bit ; the change of the torque on the upper part of the drillstring is not so large as that on the string ' s lower part , and the rotary speed of the bit changes smoothly overall
对8英寸xhp2s钻头做了仿真，结果表明，钻头处受岩石的阻力扭矩是随机变化的，并有负扭矩出现，扭矩的变化幅值随静钻压的增加而增加；钻柱顶部转盘施加的扭矩变化不如底部剧烈；钻头的转速在局部有较小的波动，其总体变化较为平缓。