Examples To Calculatory Determine The Required Speed For Your Drilling Machine - Optimum OPTidrill B 16H Betriebsanleitung

Drill bit
Ø
in mm
39,0 33 49
40,0 32 48
41,0 31 47
42,0 30 45
43,0 30 44
44,0 29 43
45,0 28 42
46,0 28 42
47,0 27 41
48,0 27 40
49,0 26 39
50,0 25 38
5.3

Examples to calculatory determine the required speed for your drilling machine

The necessary speed is depending on the diameter of the drill bit, on the material which is
being machined as well as on the cutting material of the drill bit.
Material which needs to be drilled: St37
Cutting material (drill bit): HSS spiral bit
Set point of the cutting speed [
Diameter [d] of your drill bit: 30 mm = 0,03 m [meters]
Selected infeed [f] according to the table: about 0.35 mm/rev
ϑc
----------- - -------------------------------------------------- -
n = =
Speed
π ×
d min
Set a speed on your drilling machine which is less than the determined speed.
INFORMATION
In order to facilitate the production of larger drill holes they need to be pre-drilled. This way, you
reduce the cutting forces and improve the guiding of the drill bit.
The pre-drilling diameter is depending on the length of the
chisel edge. The chisel edge does not cut, but it squeezes
the material. The chisel edge is positioned at an angle of
55° to the major cutting edge.
As a general rule of thumb it applies: The pre-drilling
diameter is depending on the length of the chisel edge.
Recommended working steps for a drilling diameter of 30 mm
Example:
1st working step: Pre-drilling with Ø 5 mm.
2nd working step: Pre-drilling with Ø 15 mm.
3rd working step: Drilling with Ø 30 mm.
Determining the cutting speed and the speed
Version 1.1.8 dated 2018-09-13
65 82 98 122 147
64 80 96 119 143
62 78 93 117 140
61 76 91 114 136
59 74 89 111 133
58 72 87 109 130
57 71 85 106 127
55 69 83 104 125
54 68 81 102 122
53 66 80 100 119
52 65 78 97 117
51 64 76 96 115
v
] according to the table: 40 meters per minute
c
40
m
(
425 rpm
=
× , × ,
3 14 0 03m
Translation of the original instructions
OPTIMUM
M A S C H I N E N - G E R M A N Y
Speed n in rpm
163 204 245 286
159 199 239 279
155 194 233 272
152 190 227 265
148 185 222 259
145 181 217 253
142 177 212 248
138 173 208 242
136 169 203 237
133 166 199 232
130 162 195 227
127 159 191 223
)
Chisel edge length 10% of the
drill bit - Ø
327 408 490 653
318 398 478 637
311 388 466 621
303 379 455 607
296 370 444 593
290 362 434 579
283 354 425 566
277 346 415 554
271 339 407 542
265 332 398 531
260 325 390 520
255 318 382 510
®
817
796
777
758
741
724
708
692
678
663
650
637
GB
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