main control valve

This is domestic-made,can widely supplied in the road header.

1)Same structure as STF series as removed piston sleeve, integrated body case and piston cylinder hole; featured with high power-mass ratio and technical performance;
2)Applied hydrostatic oil-film modality between ball-socket of piston and ball head of con-rod to heighten its contact pressure ratio, working pressure and mechanical efficiency;
3)Special surface treatment of piston guarantees its permanent structure and low-friction seal that enables its higher volumetric and mechanical efficiency;
4)higher anti-impact and load performance due to its enhanced roller bearing;
5)Longer service life due to special materials and advanced heat treatment in main transmitting parts;