There are many process concerns and challenges to this environment seen often in converting applications.
First, the word oven or dryer indicates heat. Heat related concerns include the following:
The temperature limitations and location of the bearings
• Webex standard idler bearings are good up to 350°F.
• Other high temperature bearings are offered.
• Live shaft designs often have bearings mounted outside the heated zone.
The temperature limitations of the roll materials
• Aluminum should be avoided above 350°F.
The temperature limitations of the platings or coverings
• Both linear and radial expansion must be considered.
• Aluminum dead shaft rolls will require steel bearing inserts.
• Rolls mounted in bearings must be able to "float" on one end.
Other design concerns include:
Solvents present in the drying process
The drying process often involves many chemicals that will destroy grease in bearings.
Drive components or tendency drive arrangement
Oven designs often have very little wrap on the rolls; therefore a drive may be required. If a roll is tendency driven, special considerations must be given to the shaft design.