... , drawworks, mast, traveling system and driving devices of truck mounted drilling rig are mounted on a self-propelled chassis ... load ranging from 253000lbs (1125kN) to 505800lbs (2250kN). The truck- mounted drilling rigs feature heavy working load, reliable performance, good ... hydraulic disc brake. Auxiliary brake can be of air controlled water-cooling disc brake, air tong brake, hydro brake, ...