YO18 The rock drill is used for rock drilling, blasting holes and other drilling works in the quarries, small coal mines and other constructions. It is suitable for drilling of horizontal or inclined holes on the medium-hard and hard rock. Specification Weight: 18kg Overall length: 550mm Cylinder dia: 58mm Piston stroke: 45mm Air pipe inner dia.:19mm Water pipe inner dia.:8mm Shank dimensions: 22*108mm Water pressure: 3.9-5.9*105Pa Air pressure :