Things which are Important to avoid Strip Waviness defects:
"I" Unit
A Measure of Flatness
The Unit of measurement for Flatness is the "I" Unit.
One I Unit is a measure of the amount of elongation gaugation against the shortest measured
segment and is measured as a 1/100000th part.
One I Unit is defined as the Flatness error caused by differential length (of different fibers of strip)
of 0.001% or one part in 100,000.
For Example
If a 1,000mm long length of strip (at the centre) is rolled
with its edge 1000.01mm long, then the Flatness error between
centre and edge would be 1 'I' unit.
Shape Control Methods
- Skewing Control
- +/- Roll Bending Control
- Intermediate Roll Shifting
- S Roll Type Flatness Control
- Thermal Crown Control
- Selective Cooling
Some Strip Defects/Edge Waviness |
Centre Buckles |
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Edge Waves |
Long Center & Edge Waves |
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Edge Wave |
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