Internal steam pressure cure

Internal steam pressure cure - A rubber-lined vessel which can be sealed and is structurally strong enough to take steam pressure during cure. Examples are railroad tank cars and chemical reactors. 

Rubbers are also being extruded, in a not essentially different way from plastics. Cooling of the extrusion cylinder is necessary to prevent premature vulcanisation as a result of the heat developed by internal friction. The extruder is fed by ribbons, obtained from milled sheets. End products are hoses, profiles, and cable mantles. On-line vulcanisation can be achieved by passing the extrudate through a steam channel, while the rate of extrusion is adjusted to the rate of curing. For this purpose high-rate vulcanisation recipes have been developed. Steam temperatures of about 200 °C are being applied (15 bars pressure). Treads for motorcar tyres are also extruded they are wrapped round the pre-formed carcass and then formed and vulcanised in a press. 

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