ring-oil bearing油环润滑轴承

piston ring gap clearance-oil control油环开口间隙

inner-ring oil-flow环下供油

double-ring oil seal双剖分油封

double-ring oil sealing双流环形油密封

single-ring type sealing oil system单流环式密封油系统

double-ring sealing oil system双流环密封油系统

O-Ring for oil vat油缸密封圈

oil ring self-lubrication油环自动润滑