The curing foreman checks the Shop Order to identify the mandrel needed for the order. The mandrels are pulled from the rack and the raw rubber tubes are slipped over them. Depending on a variety of factors, the raw rubber tubes may then be wrapped down tighter onto the mandrel. It is now ready to be cured (vulcanized).
The tubes are then placed into an autoclave (similar to a giant pressure cooker) where the rubber is vulcanized against the mandrels. This process not only cures the rubber but also sets the tubes’ inside diameter. The tubes are then taken to the grinding department where they will have their outside diameter set.