Cutting chisel edge with high centring accuracy due to strong core and special point geometry. High roundness and alignment accuracy of the deep hole, thanks to 4 guide chamfers. Outstanding chip evacuation due to 4 internal cooling channels from ⌀ 3.8 mm. Up to 3.7 mm ⌀ with 2 internal cooling channels. Straight major cutting edges with honed edges and special flute profile for short chips, even on long chipping materials.
Maximum drilling depth:
flute length (see table) less 1.5×nominal ⌀.
For process reliability when using the 12×D deep-hole drill, an initial centre drilling with No. 121068 – 121130 or 3×D pilot drilling operation with No. 122736 is necessary.
Form HB and HE supplied at the same price as HA.
Form HB: order with No. 123214.
Form HE: order with No. 123212 + 129100HE.