air /petrol /electric rock drill from china type:YT24,YT28,YN30,YN30A,YN30E,YN27,YN27C,YN27T ... the temporary projects that the machine has to be carried at any time and in any place. 4. In operation, ... it can be handled horizontally, vertically downward, or upward at an angle below 45°. When turned vertically downward, it can ... forty degrees below zero Air /petrol /electric rock drill from china