ACE, now a part of Benko Products, has provided Burn Off ovens for various customers that want to reclaim or reuse metal wheels and rollers. This can be anything from roller coaster wheels to rubber rollers used in office equipment.
Various types of rubber are used and it is important to know what kind of rubber that needs to be removed. Natural rubber, neoprene and other “natural rubber” is removed fairly easily although a different type of cycle may be necessary due to the large amount of smoke that is generated. The afterburner on our ovens can only handle a certain amount of combustibles. If the oven is overloaded, smoke can escape through the exhaust stack. Therefore we can extend the cycle times to slow the process down a bit to handle the smoke. Rubber on metal parts generally have a large amount of rubber. Seeing a wheel or roller with 2” of rubber is not uncommon.
Urethane is a different matter. When urethane is burned, it gives off a corrosive gas. The steel interior of the oven, the cart, etc. can become corroded and fail after only a few years. To counteract that corrosion, we can provide some protection. We have used a Viton coating on the interior of the oven shell and then we have placed Stainless Steel foil in between the insulation layers on the walls and ceiling. I recently quoted a customer, Johns Manville, on an oven with the SS foil as they are replacing an oven that had the same option. Their existing oven lasted 22 years.
We can also provide a third water suppression system for customers processing rubber. During the heating cycle, the adhesive holding the rubber to the metal fails and the rubber falls away. The rubber can still be only partially burned and can lay on the floor of the oven. The third water system helps to extinguish any rubber that is smoldering on the floor.
Take a look at the attached photos of rubber rollers before and after processing in our test Burn Off oven.