Description
GRAFF drill bits, Set of 10 are made of HSS steel by rolling (screw-rolling) method with ground edge according to DIN338 standard. Drill bits have a cylindrical shank for a drill. Angle at the apex of 135 degrees and cross undercutting provide excellent drilling of metal without pre-drilling. Drill bits are used for drilling bores in alloyed and unalloyed steels, malleable and gray cast iron.
| Diameter, mm | Total length, mm | Working part, mm | Recommended rotations per minute, rpm |
|---|---|---|---|
| 1 | 34 | 12 | 5740 |
| 2 | 49 | 24 | 4780 |
| 3 | 61 | 33 | 3820 |
| 4 | 75 | 43 | 2870 |
| 5 | 86 | 52 | 1910 |
| 6 | 93 | 57 | 1720 |
| 7 | 109 | 69 | 1530 |
| 8 | 117 | 75 | 1340 |
| 9 | 125 | 81 | 1150 |
| 10 | 133 | 87 | 960 |
