... : pneumatic breaker tools,mining tools,rock tools,rock drill,leg drill,atlas copco,drifters Air-leg Rock Drills yt27,yt24,yt28 application:YT27 ... most fit for drilling horizontal and inclined blastholes in medium-hard and hard rock with a hardness of (f=8-18) .YT28 may ... (mm) Water pipe inner dia φ13 (mm) Rock drill hole dia φ34~φ42(mm) Rock drill hole depth 5 (m) Shank size ...