TOS SUA 125 NUMERIC - Page 24

SUA 125 NUMERIC
34200003 TOS a.s. 02/2011
24
follows:
1. Safety instructions for regular application of workpiece chucks.
2. Information for user how to determinate the clamping force and select the suitable chuck.
3. Information of clamping force change during rotation of chuck equiped with the standard moving chuck jaws.
4. Information of max. admissible mass of moving chuck in max. radius and max. speed.
5. Information of min. adjusting jaw distance for effective clamping.
6. Information of the method of clamping force determination for special moving jaws.
7. Instructions for maintenance including lubrication and time intervals in measuring of the static clamping force.
8. Information for workpiece exchange referring to ISO 3089 and ISO 3442.
9. Description of the conditions which should be fulfiled between workpiece chuck and its controlling device. (eg. in case of
using a clamping cylinder).
When using the workpiece chucks the operator should be follow the requirements of their manufacturer as follows:
- the workpiece dimensions recommended to chuck should be respected in relation to the possibility of starting risk factors,
- on the basis of requisite clamping force and kind of clamping of workpiece, max. admissible speed should be determined,
- stress analysis of dynamical clamping forces should be made for special adjusting jaws of workpiece chuck in accordance
with the method mentioned in the directions for use by the chuck manufacturer,
- the measuring of the static clamping force should be made for verification of the maintenance quality in regular intervals
in accordance with the maintenance chuck instructions,
- avoid the residual risks which can start from faults resulting from the effort of reaching the satisfactory quality of rotary
balance of workpiece and chuck,
- the controlling force intensity for the safe clamping should be respected.
The safe operation of workpiece chucks is assumed that the clamping force will be constant in course of machining process.
For this reason the chucks should be provided with following data by the manufacturer:
- name or marking,
- CE marking,
- type marking or serial number,
- max. admissible starting force or torque,
- max. static clamping force with max. starting force (torque) measured in new chuck and lubricated in
accordance with the manufacturer intructions,
- max. chuck speed.
CAUTION: The detailed data about max. speed and max. static clamping force of workpiece chuck must be applied by the
operator to the following cases:
- if the cutting force variation is occured.
- if the chucks are the source of noise and vibrations.
- if the speed is dangerous from point of view of chuck permanent damage. This case comes usually into the
consideration if the chuck body is made from grey cast iron.
- as far as the clamping force required for a certain case of the machining is unknown in advance.
- as far as the actual clamping force set for a certain case of machining is unknown by the chuck manufacturer.
Warning: When determining the clamping force and speed of the workpiece chuck it is necessary to get to know that its
intensity is reduced by the action of the centrifugal force and other effects in consequence of:
a) overspeeding set for the certain case of machining,
b) mass and type of non-standard clamping jaws,
c) different diameters of workpiece against jaws,
d) unsuitable conditions for chuck - e.g. excessive lubrication,
e) the state of workpiece unbalance,
f) the intensity of peripheral cutting forces,
g) the clamping method of workpiece by means of jaws (external or internal clamping).