The type RT 100 U ratio drills available from Guhring Australia are used for the drilling of long and short chipping material, such as cast steels, heat treatable steels and case hardened steels.
The type RT 100 U ratio drills can also be used with alloyed steels that have a tensile strength of up to app. 1200 N/mm2 which include high-alloyed AlSi-alloys, cast iron, carbon steels and bronze.
The concave cutting point geometry, with special point geometry and web thinning, of the type RT 100 U ratio drills enables production of short chips as well as providing self-centring qualities. The drills also offer small diameter tolerance and alignment accuracy.
Ratio drills are also available with internal cooling and with straight shank. But this is without whistle notch flats for application in hydraulic chucks.