Major producers of automotive and truck tyres usually produce radial tyres by curing the various rubber compounds in the tyre at elevated temperature and pressure, in a large tyre press containing a mould for the tread design. High-pressure nitrogen and steam can be used to mould or "cure" the rubber in the pre-assembled "green" tyres.
 The use of nitrogen and steam provides two key benefits. First, by controlling temperature by injecting steam and by controlling pressure by injecting nitrogen, the producer can generate a curing cycle in which the temperature and pressure can be somewhat independently varied for optimum results. This enables the tyre producer to avoid the use of high-pressure hot water systems with corrosion and maintenance problems, or endo gas generators with their inherent safety and reliability problems. The other key benefit is the ability to minimise oxygen content in the system, which results in improved life of the bladder on the tyre press, as well as reduced corrosion in the system.
Nitrogen at about 400–600 psig (27–41 bar) is injected along with steam into a bladder or inner tube which is inside of an uncured rubber tyre in a tyre press. The pressure forces the green tyre to conform to the shape of the mould and forces air out from between the many layers of the tyre. Air Products will evaluate and design the required high-pressure nitrogen gas delivery system. In addition, we provide expertise and know-how regarding the valves and piping for handling the high-pressure gas in the tyre press area, as well as safety training.
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