Turning - Rohm Norm RN 1391 Informaciones Y Directivas Generales Para El Empleo De Instalaciones De Sujeción Accionadas Por Fuer

2 | Reference Speed and Clamping Force Calculation
2.1.3

Turning

Re. a) "Calculating the required clamping force F
Required Clamping Force of a Power Chuck [} 40])
The clamping force required depends on the type of work to be performed.
The cutting force on the turning tool results in three components:
Main cutting force F
During the turning process, the feed force F
mainly absorbed by the contact surface of the workpiece on the jaws. When
turning, the remaining main cutting force generates a torque (F
must be absorbed by the chuck and transmitted by friction at the clamping
point.
The torque produced by the main cutting force during turning determ-
ines the clamping force required.
where:
F = clamping force required for a specific job with the chuck stationary
spz
F = main cutting force
s
Clamping ratio
μsp = clamping coefficient (friction between jaw and workpiece)
S = safety factor
z
The components "feed force F
formula. If necessary for extreme conditions, they are included in the safety
factor S .
z
Main cutting force F
F = s ∙ t ∙ k
s
where:
s = feed mm/rev.
t = depth of cut, mm
k = spec. cutting force kN/mm²
c
The product s x t (feed x depth of cut) = chip cross-section (can be obtained
from Table 1)
42 / 138
- Feed force F
s
(1)
machining Ø (processing Ø)
is calculated from feed, depth of cut and material.
s
(2)
c
- Passive force F
v
and the passive force F
v
clamping Ø
" and "passive force F
v
" (see Determining the
spz
.
p
x d
s
" are not entered in this
p
are
p
/2) which
z
RN-1391