MILL LOAD - Roll Force,
Torque, Power
The
Mill Load application is specifically developed for mill
design/operation engineers to calculate roll separating force,
rolling torque and power, etc.
Typically, load
calculation is needed for an existing mill when a new rolling
process is applied either with higher reduction or in lower
temperature or higher speed, or for a stronger material.
This is to make sure the force, torque, etc. are not over
equipment capacity. In building a new mill, motor selection,
mill size determination and transmission system design, etc.
are all based on mill load calculation.
Applications in this section consist of:
This suite of mill
applications are based
on our sophisticated
rolling mill process
models, especially those
to determine force,
torque and power
requirement. The model
have been developed and
continuously improved
for the past 20 years
with extensive mill test
results in Germany and
USA, etc. For high
accuracy of prediction,
every detail involved is
carefully determined.
For example
-
Projective contact area. Elementary slab
method is used by constructing imaginary contour, together
with modifications from spread, pass sequence and fill ratio, etc. For
some passes, contact area models are used based on
experiment
results on the shapes of
contact areas in various pass sequence.
-
Mean flow stress. The strain along the contact
length ranges from 0 at the entrance, to the max. strain (pass
strain) at the exit. A mean (or average) strain is used
to achieve high accuracy.
Flow stress
model is
specifically
developed for a
wide strain rate
range 0.05-500/s
(applicable up
to 3000/s); so
the model is
sufficient to
cover the modern
finishing block
case with
rolling speed
over 100m/s.
-
Shape factor (Q factor). This factor covers pass
sequence, entry billet shape
and contact, etc. The shape factor model used
is among those developed through a ten-year rolling process
research in a four-stand high-speed continuous mill (speed up to over
70m/s).
-
Lever arm ratio. During torque calculation, experimentally established model for lever arm ratio
in each pass sequence is employed, besides the accurate calculation of the
roll separating force.
Related Resources
On Rolling Mill Process Modeling
- Empirical Models
Metal Pass Roll Pass Consulting
Do-It-Yourself Improvement: Ask
A Question
Flow
stress and modeling
Roll pass related US patents
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