Trepanning tool for metal - has spring loaded point ensuring correct centring and can include extension lengths for producing deep holes

摘要

The trepanning tool has a taper shank (12) and an adaptor (18) at the other end for locating the cutting head (14). The assembly is made by means of collars (38) screwing inside the head. A stationary ring (23) is on the head to provide a fixing for a coolant supply, rotating seals (26 to 29) being provided. Extension pieces (13) can be fitted between adaptor and cutting head for producing deep holes. The cutting head has a centre point (45) which ensures correct location when commencing a cut. This point is fitted with dished spring washers (48) and forms a piston (51) sliding back inside a cylinder (64) as the cut progresses.