Rust inside furnace rolls?

[dfrank]

We use a ceramic roll with a steel shaft in a furnace on a Cold A&P line. A descaler is used to rinse the ID at the manufacturer, but the ends are not capped when delivered. Should they be, and how is the inside rusting after a descaling process? How can we prevent this?

 

[rhodie]

I'd suggest condensation is creating the flash rusting you are describing. Find a way to eliminate temperature differential, and you might solve your problem.