GUHRING Deep hole drill FS SC TiALN shank HA int. cooling 12.0mm

Deep hole drill, 20 x D

RT 100 T method: • Mill a surface at right angle to the start angle of hole machining. • Produce a cylindrical pilot hole (tolerance F9) with a drilling depth of at least 1 x D. • Insert into the pilot hole with approx. 300 rpm at f = 500 mm/min. • Set the cooling lubricant pressure and speed. • Continual drilling to full drilling depth without relief cycle. • For through holes with an inclined exit, reduce the feed rate v f to approx. 1 mm before breaking through to 40%. • After reaching the drilling depth, switch off the rotation and coolant, extract in rapid traverse. • Conventional coolant lubrication min. 40 bar. Note: The drills can be sharpened several times. All deep holes must be piloted before starting to drill.Deep hole drills should never be moved freely in the machine when at the full speed.

Design: Right cutting. Special groove shape with double bevel and special grinding. With twisted internal cooling through the bar. Normal angle of rake 30°, core thickness thicker than normal and without core gradient. The drill has a very good self-centring behaviour. Application: For drill holes with very narrow Ø tolerances and very good surfaces. Suitable for drilling extremely deep holes up to 20 x D with high cutting speeds. Especially for short-chipping materials such as cast iron, grey cast iron, tempered grey cast iron, tempered and nodular cast iron and aluminium alloys with a high silicon content.