... not only hard alloy innercooling drilling head to drill with high speed, but also high-speed steel twist drilling head. 2. It also ... CNC controlled, very convenient to operate, Automation, high precision, variety, medium and small batch production can be realized. 3. ... drill at the same time, high efficiency. Two kinds of drilling heads, BTA or gun drill. Can clamp workpiece of Φ4000mm,drill hole ...