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3 unbalance functions, Unbalance while turning, Unbalance functions – HEIDENHAIN TNC 640 (34059x-04) ISO programming User Manual

Page 449: Unbalance functions 14.3

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Unbalance Functions 14.3

14

TNC 640 | User's Manual for DIN/ISO Programming | 3/2014

449

14.3

Unbalance Functions

Unbalance while turning

General information

The machine has to have been adapted by the

machine manufacturer for monitoring and measuring

unbalance. The unbalance functions are not required

some machine types. These functions might not be

available on your machine. Refer to your machine

manual.
The unbalance functions described here are basic

functions that are set up and adapted to the machine

by the machine manufacturer. The scope and effect

of the described functions may therefore vary from

machine to machine. The machine manufacturer may

also provide different unbalance functions. Refer to

your machine manual.

In a turning operation, the tool is in a fixed position, whereas the

rotary table and the clamped workpiece rotate. Depending on the

size of the workpiece, the mass that is set in rotation can be very

large. As the workpiece rotates, it creates an outward centrifugal

force.
The centrifugal force that occurs basically depends on the

rotational speed, the mass and the unbalance of the workpiece. An

unbalance occurs if an object with a rotationally nonsymmetrical

mass distribution is set in rotation. The rotation of the mass object

creates outward-directed centrifugal forces. If the rotating mass is

evenly distributed, the centrifugal forces cancel each other out.
Unbalance is significantly influenced by the structural shape of the

workpiece (e.g. nonsymmetrical pump body) and by the chucking

equipment. As these factors frequently cannot be changed, you

should compensate any existing unbalance by means of balancing

weights. The TNC provides the "Measure Unbalance" cycle for

this purpose. The cycle determines the existing unbalance and

calculates the mass and position of the required balancing weight.