... prop is constant-resistance prop with hydraulic oil supply outside.as the pioneer of designing and manufacturing this equipment in China,we ... as driven medium.all the key parts(movable prop,cylinder,pedestal,rest spring,etc.)adopt advanced erosion resisted technology ,and can ... )3.83.83.83.83.8SHORING POWER(kN)3030303030INNER IAMETER OF HYDRAULIC CYLINDER(mm)Φ100Φ100Φ100Φ100Φ100RELlEF VALVE RATED ...