Speed Information, Maintenance Recommendations, Reference Speed; Influencing Factors That Significantly Impact The Tensioning Force - Optimum OPTiturn TH4610D Betriebsanleitung

The maximum rotational speed of a lathe chuck may only be applied at maximum actuating
force and with perfectly working chucks.
Lathe chucks must be designed for the maximum rotational speed of the machine, the
permissible lathe chuck speed with respective jaws and/or top jaws, as well as the maximum
measured static clamping force at maximum introduced force must be specified in the operating
instructions for the lathe chuck or be indicated on the lathe chuck itself. Replacement lathe
chucks must comply with EN 1550 standards. The minimum distance to the machine bed must
not be less than 25 mm.
WARNING!
Do not clamp any workpieces that exceed the permitted chucking capacity of the lathe
chuck. The clamping force of the chuck is too low if its capacity is being exceeded. The
clamping jaws may loosen.
Only use lathe chucks designed for the speed of the machine.
Do not use lathe chucks with an external diameter that is too large.
Please ensure that lathe chucks are manufactured to EN 1550 standards.

4.14.1 Speed information, maintenance recommendations, reference speed

in accordance with DIN 6386
The reference speed is the number of rotations, at which the mathematical centrifugal force
with the corresponding jaw design correlates with the greatest tensioning force when the
machine is at a standstill. The reference speed applies for jaws mounted inside in tiers,
whereby they must not protrude past the outer diameter of the chuck.
At the determined reference speed, 1/3 of the tensioning force which is available when the
machine is at a standstill, is available for clamping the workpiece. The prerequisite is that the
clamping chuck is in proper working order.
In general, the labels on the clamping jaws and lathe chuck (perm. speed, max. turning
diameter, ...), the information in the respective lathe chuck operating instructions and, for
special jaws, the additional information on the respective drawing must be observed.
The lathe chucks included in the scope of delivery cannot be used with top jaws.

4.14.2 Influencing factors that significantly impact the tensioning force

Clamping jaw centrifugal force
To calculate the required tensioning force for processing a workpiece, the centrifugal force of
the clamping jaws must be taken into account.
The permissible speeds can be determined in accordance with VDI Guideline 3106
"Determining the permissible speed for lathe chucks (jaw chucks). This guideline also allows for
the residual tensioning force at a specified speed to be determined.
Version 1.0.6 - 2022-5-17
Fc Centrifugal force in N
m Mass in kg/set
rs Centre of gravity distance to the centre of the chuck in
metres
n
-1
Speed min
r Centre of gravity distance to the clamping jaw
0
Translation of original instruction
TH4610 | TH4615 | TH4620 EN
151