... /electric rock drill from china type:YT24,YT28,YN30,YN30A,YN30E,YN27,YN27C,YN27T certificate:ISO9001,CE super air /petrol /electric rock drill ... petrol engine, an air compressor and a rock drill. 2. During operation, the rock powder is blown away by the compressed air ... maxim depth of 6m. Applications1. The machine is used for rock drilling. It can be converted into a breaker or a ...