Reference Speed And Clamping Force Calculation; Power-Operated Clamping Devices; Reference Speed - Rohm Norm RN 1391 Informaciones Y Directivas Generales Para El Empleo De Instalaciones De Sujeción Accionadas Por Fuer

Incorrect
Workpieces with cast iron or forged
tapers
2

Reference Speed and Clamping Force Calculation

2.1

Power-Operated Clamping Devices

2.1.1

Reference Speed

When using clamping jaws, the following instructions must be observed:
▪ The clamping jaws should be designed in such a way that their weight and
height is as low as possible. The clamping point should be as close as
possible to the frontside of the chuck. (Clamping points at a larger dis-
tance may cause a higher surface pressure in the jaw guiding mechanism
and may thus reduce the clamping force considerably).
▪ If the special jaws are for design reasons wider and/or higher than the
step jaws assigned to the clamping device, the resulting higher centrifugal
forces must be considered when calculating the required clamping force
and the reference speed.
For calculating the rated speed for a certain machining task the follow-
ing formula is to be applied:
F = initial clamping force with the chuck at standstill (N)
spo
F = required clamping force of the chuck for a certain machining task (N)
spz
n = max. speed (rpm)
max
m = mass of the entire jaw unit (kg) (base and top jaw)
r = centre of gravity radius of the entire jaw unit (m)
c
a = number of jaws
RN-1391
Reference Speed and Clamping Force Calculation |
Correct
Clamping with self-seating inserts
2
EN
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