... and Advantages1,With hydro-automatic feeding device, and high drilling efficiency. 2, Convenient to operate, safe ... 60,φ73,φ89,φ95,φ133Thru-hole diameter of power headφ35,φ60,φ81,φ120The size of ... and reverse circulationApplicable impactorMedium wind pressure,High wind pressureLifting speed of power head (m/s)0.25 0 ... .4 94.55Pressure capacity(kN)0-15Speed of power head(r/min)Group A (corotation 13,22 ...