Grinder for removing swelling on hot rolls

[pdentrem]

This has been idling for a very long long time.
Rolling mill rolls are ground flat but when heated they expand but not equally across the working length, as the heaters are usually in the center and the end which are near the oil cooled bearings are naturally cooler. So naturally the material rolled is slightly thinner in the center by a few tenthousandths. In the past we tried using CNC grinding but total failure and reground the rolls back to flat. The next attempt was to use a large diamond wet stone and basically flattened the center. This worked but what a job!
I had designed a power grinder to do this quicker but management was lukewarm. Finally a couple months ago, we were given the go ahead to build it.
Per the photos the two long rods sit the grinder on the top of the roll and the two brass faced (still need to trim the brass) will register and the wheel will slightly contact the rolls and remove a couple thousandths. We only need the 2-3” of the center done and the rolls are 6” across. The wheel is 400 diamond grit and 4” in diameter.

Hopefully the photos are semi coherent!
Pierre

 

[Dan Dubeau]

I'm not going to pretend I know anything about the application and use of it, but I can appreciate the creative problem solving, and machining that went into that custom tool. Well done! Show us some pics of it in action, if you're allowed so we can understand how it works more.

Ok, I took a couple more looks at the pics and re-reads of the description before posting, and If i'm understanding it right, I'm guessing this is how it's used? Front/side view showing only the important stuff. Blue are the long rods, green the grinding disc, and the gold are the brass posts. The brass and long posts register on the outside roll diameters at the end, and the brass ones control your depth of cut? If so, that seems like a pretty great, and simple way to accomplish that task. Should be a time saver for sure.

 

[pdentrem]

That is right. We believe this should work as we are just removing a small amount of metal and not in a rush to do so. Going to set it up next week and try it. Fingers crossed!
Pierre