Formulas, Thread turning formulas – Sandvik Coromant Threading User Manual
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apx
=
a
p
nap - 1
√
√
5. Technical reference
Formulas
Use the following formulas as a reference for successful thread
machining.
Thread turning formulas
Infeed
(Manual formulas, when not using the Sandvik Coromant calculator)
Δap = Radial infeed
X =
Actual pass (in a series from 1 to nap)
a
p
=
Total depth of thread + extra stock
nap =
Number of passes
=
1st pass = 0.3
2nd pass = 1
3rd and higher = x-1