Shank Hex 22X108mm 25X108mm 7degree 12degree Rock Stone Quarry Drilling Taper Steel Bar Rod

Shank Hex 22X108mm 25X108mm 7degree 12degree Rock Stone Quarry Drilling Taper Steel Bar Rod

Different rock formations and rock drills require different taper angles. When drilling with high impact hydraulic rock drills in medium-hard to hard and abrasive rock formations, a wide taper angle is normally used. Taper angles of 11 and 12-degrees are normally used on modern drill rigs. For low impact rock drills and softer rock formations, a narrow taper angle of 7 degrees is used. A 7 degree angle can also be used if bit spinning is a problem when using 11 and 12 degree equipment. In addition, a 4.46 degree angle is ideal for soft rock when you're using pneumatic or hydraulic drill rigs to prevent bits from spinning or becoming detached.