... to fifteens excavator.It can drill 24mm-46mm dia hole.Drilling speed can be 0.8-1.2m/min DangShan DS30 hydraulic ... rock drill is a new generation drilling equipmentsof our factory ,which takes more than 18 year careful ... product has many outstanding features: small original driving force, fast speed, stability control, low noise,simple,reliable, easy maintenance, flexible ...