Worth Knowing: Selection Criteria for Rotary Indexing Tables

Before purchase following questions should be considered:

1. Mode of operation

  • Rotary Indexing Tables uniaxial
  • Rotary Indexing Tables multiaxial

2. Workpiece sizes

  • geometry
  • weight
  • mass moment of inertia

3. 3. Type of axes – activation of Rotary Indexing Tables

  • Rotary Indexing Table directly integrated in machine control (as one more machine axis)

    Advantages:

    no additional control necessary
    simultaneous operation (Turn&Burn) possible
    cost-efficient and high efficient manufacturing solution for modern machines

    Disadvantages:

    applicable only on machines prepared for this

  • Rotary Indexing Table integrated by separate control (communication via M-command of machine)

    Advantages:

    universal solution for all Rotary Indexing Tables
    quickly applicable on other machines (WEDM, SEDM, EDM drilling)

    Disadvantages:

    additional, separate control necessary  
    fits only for positioning, simultaneous operation (Turn&Burn) not
    possible


4. Selection of measuring system accuracy

Accuracy of Rotary Indexing Table is proportionally depending on accuracy of direct measuring system (angle encoders, encoders).
They are available in various classes of accuracy (higher accuracy = higher price).
 
The diagram shows that for small workpiece diameters linear positioning error (straight distance) is not very high also for less accuracy of measuring system but for larger workpiece diameters may occur large deviations.  
 
As standard angle encoders with accuracy +/-5" or +/-10" are used (other accuracies on request).
 
Diagram Genauigkeit Rundteiltisch Auswahl

Example:

Max. positioning error depending on system accuracy and workpiece diameter

Workpiece diameter
50 mm 100 mm
Measuring system accuracy +/- 5 seconds +/- 0,0012 +/- 0,0024
Measuring system accuracy +/- 10 seconds +/- 0,0024 +/- 0,0048