... DTH hammer: 1,with drill 2,road paving, quarry, mine exploiting 3,trinity design in joint 4,everyone is tested before delive Drill ... perforation, rock operations. Drill Impactor advantaesQC70/80/90/100 DTH-impact, uses a single piston, valves and the board after ... can not directly adjustable joints and drill pipe connections, reducing production costs. Second, the drilling and diameter taper when Card ...