traction aid牵引装置tractionn.拽；牵引；牵引力；附着磨擦力traction performance牵引性能traction dynamometer拉力测力计,牵引力测力计traction speed lever前进速度调节杆traction transtormer牵引变压器traction substations牵引变电所traction calculation牵引计算traction drive shaft驱动轮传动轴traction rope sleeve牵引索套traction-type cell牵引型电池traction andfixation牵引固定