unlubricated bearing无润滑轴承
unlubricated sliding无润滑滑动
unlubricated surface无润滑表面
unlubricated compressor无油压缩机
unlubricated friction干摩;无润滑摩擦
unlubricated wear金属无润滑磨损
unlubricated forward extrusion未润滑正向挤压
unlubricated friction and wear摩擦磨损
Unlubricated or lubricated service润滑或润滑服务