Rotary Table is a precision work positioning
device used in CNC machining centers to precisely position the component in
desired angle to do multi-face operation in a single setup. Rotary tables can
be interpolated as 4th axis with machines X,Y and Z axes to enable machining of
profiles such a cam machining, blade machining, helical grooves etc. which is
out of reach with a standard 3 axes machining center.
Based
on the application one can use only the Rotary Table with some work holding
fixture or will have to use some accessories like Dead Center or Revolving
Center Tailstocks, Face Plate Tailstocks, Manual or Power Chucks etc.
There
are some basic points which needs to be checked for correct sizing of Rotary
Table.
Rotary Table selection guidelines
1.
Rotary Table Selection based on Component Size
·
Check for the swing
required on the component
·
Check for Center Height of the Table
·
For Multi spindle
Table check for the center distance between the spindles
·
In vertical
condition if the length of the component is more than 100 mm it is recommended
to use the tail stock support
·
Larger component
can be used provided load and clamping torque is within capacity of the Rotary
table. For larger swing use height Block.
2.
Rotary Table Selection based on Clamping Torque
·
Check for the
machining forces required to do the operation.
·
Check for the
distance from the center where operation is to be carried out.
·
Calculate torque
applied during machining ( Torque = Force x Distance)
·
Machining torque
should be with in Clamp torque capacity of the Table
·
Check for the type
of clamping required (Hydraulic or Pneumatic )
3.
Rotary Table Selection based on Component Weight
·
Check the dead
weight of the component and fixture.
·
The dead weight of
component & fixture should be within the capacity of Load capacity of the
Rotary Table.
·
With tail stock
support Load capacity of the Rotary Table in vertical condition will become
same as horizontal load capacity.
4.
Rotary Table Selection based on Indexing Accuracy
·
Check for the
accuracy requirement on the component.
·
If accuracy
specified in mm, check for the diameter at which the accuracy is required.
·
Convert Indexing
Accuracy of the Rotary Table specified in arc sec to mm at the diameter where
the operation is to be carried out
·
(A = Tan Ө x R),
o
Ө = Indexing Accuracy (Ex: +/-
15” (30”sec))
o
R = Radius at which
the operation to be carried out
o
A = Accuracy in μ
·
NOTE: Higher
accuracy of +/- 5” can be achieved by using additional high resolution encoder
mounted on the table axis.
5.
Rotary Table Selection based on Machine Capacity
·
Check the Machine
Strokes and ensure once Rotary Table is mounted on the Machine Bed, component
falls in the machining area.
·
Also check for the
Tool change position. While tool changing the tool should not foul with Rotary
table.
·
Total weight of the
Rotary table including the work holding should be with the capacity of the
machine load capacity.
6.
Rotary Table Selection based on fouling with
machine guard
·
Check for fouling
of Rotary table Sheet Guard with Machine guard after mounting on Machine bed
locating on the center tenon slot.
·
If there is fouling
we can use Rear Motor mounting Table, provided there is sufficient space
between Machine table and Machine sheet guard when table is in extreme right
hand side.
7.
Rotary Table Selection based on controller
feasibility
·
Check if Machine
Controller is capable of taking 4th axis for single axis table and 4th and 5th
axis for two axis tables.
·
We can also suggest
stand-alone controller if the machine is not capable of handling 4th axis,
provided component does not need
continuous interpolation with machine axes for performing the operation
·
In some cases
controllers are capable for 4 regular axes and 5th axis can only do indexing.
We
would be happy to assist you to provide correct selection of Rotary Table and
its accessories. For more details please feel free to write to us at marketing@ucamind.com
No comments:
Post a Comment