Prodn. appts. for hollow rubber objects

摘要

The unvulcanised rubber item is put in a vessel which is then sealed at both ends except for an outlet to a vacuum pump. The inside of the rubber item is pressurised so that it expands to touch the wall of the container. Any remaining air is removed via by a vacuum pump. The valve to the vacuum pump is closed and the excess pressure within the rubber item is reduced. The item remains in contact with the wall of the vessel where it is then vulcanised. The vulcanising medium can be hot air.