Thickness Controlling in 2Hi Cold Rolling Mill

Probably in the owners manual....

If not, then the manufacturer's telephone number certainly will be. The Original Poster did ask for <...anyone...>, after all...

<...anyone...> <...some one...>

Ask here: Vaid Engineering Industries - Manufacturer of Cold Rolling Mills ...

About 3 decades ago I did the controls for a rolling mill for nickel.

We used diamond pointed LVDT's on both the in-going and out-going strip.

The rolling force causes the mill frame to stretch - so if the in-going strip becomes thicker then the mill needs to screw down to have the required out-going thickness.(Feed-forward control). Obviously there is a time lag between the in-going measurement and when that thickness reaches the rolls. A delay based on strip speed for the screw down has to be programmed so the mill is not tightened prematurely.

The outgoing measurement is a check on the result - but again it tends to be past history, so all you can do is have a small adjustment to keep the average gap correct to achieve the final measurement. This is calculated between the incoming thickness, how far the mill was closed, and the final result,

There was a lot of math involved, and test measurements made for the setup. Once setup it was amazingly accurate.

The science of how the rolls reduce the material and the selection of roll diameters, power, etc. is another topic on its own.

In aluminum, you can't touch the strip, so LVDT sensors with very high accuracy are connected to the roll bearing housings, measuring actual displacement of the rolls. Add to that sensors reading the force in the stack, load cells, from which you can calculate the bending of the bearing housings and the mill rolls . A mathematical model of the mechanical components including deflection cross machine and stretch in the vertical direction is used to calculate the mill roll gap, setting the thickness of the product. On line radioactive gauges that directly measure the strip thickness coming out of the rolls are used to control the loading of the roll stack, often with very high pressure hydraulics loading the roll stacks, to give fast feedback response to changes in the process, temperature and metallurgy. This sort of control system is sometimes referred to as AGC, automatic gage control.

The shape of the strip in the cross direction is very important, so the thickness is not uniform across the width, to reduce edge cracks and other stresses, this is part of the thickness control, shape control.

Depending on the depth of explanation you are looking for, use search term cold roll mill AGC and you will find a wealth of information from which you can narrow your request for information. The metal you are working with, the compatible solvents/lubrication, roll friction, temperature rise during rolling, all very complex subjects that can be simplified by zeroing in on your actual machinery.

This is off topic. Dear mr moderator :

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Tag / two high cold rolling mill