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What is the classification of iron pipes?

2019-07-04 839
Iron pipe fittings can be divided into three types: injection, coating and rolling. The two most popular methods are coating or rolling. They are sometimes abstractly referred to as plastic-lined pipe fittings. But even if it is painting and rolling, there are substantial differences in technology and application effect between them.
Iron pipe fittings are generally coated with epoxy resin powder in the interior of ductile iron grooved pipe fittings. However, this kind of pipe fittings are not as sophisticated as the thermoplastic grooved pipe fittings in technology, because its internal plastic adhesion is not as good as the thermoplastic grooved pipe fittings.
Thermo-rotational grooved pipe fittings are high temperature composite cold and hot water general PE inside the grooved pipe fittings. The bonding force is appropriate and firm. Destructive experiments with knives show that it is difficult to cut off the inner liner PE layer of the pipe fittings made by thermal rolling process.
Injection pipe fittings are a kind of composite pipe fittings which are made up of grooved pipe fittings and injected PP by injection moulding machine.

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