DIN338 Twist Drill Bits HSS-R HSS-G HSS Cobalt

DIN338 Twist Drill Bits HSS-R HSS-G HSS Cobalt
Short twist drills have a rank angle (sometimes referred to as angle of twist)
of 27°, a point angle between 118° and 135° as well as a cylindrical shank.
Type N is suitable for standard chipping materials. A distinction is made
between roll forged and fully ground twist drills, depending on the production
process.

When producing roll forged drills, the slugs are heated and formed into spiral
coils. Fully ground drills get their spiral coil cut while being fully
hardened. For a better distinction between the diff erent types of twist
drills, the following finishes are assigned to the different drills:

Standard DIN338
Form Type N
Material HSS-R/HSS-G/HSS-E
Tolerance H9/H8
HRC 61-66
Surface Bright/Black/Golden
Point Angle 118° for HSS Rolled Drill Bits
135° Split Point for HSS-G/HSSE from 3.0mm
Helix Angle 20-30°
Cutting Direction Right

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