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PUF Pipes Manufacturing Methods |
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Heat insulated and waterproof tubes are usually produced in the form of “annular tubes”. There are two basic methods of polyurethane foam tubes production. The first approach is a tube polyurethane coating by means of spraying or deposition. The second method is coating of a pipe with a polyurethane foam shell which is produced separately. In subsurface pipelining those waterproof pipes are used which are made of low pressure polyethylene (polyethylene mantle-pipes). Spiral lockseam tubes produced from galvanized steel band are used in above-ground pipelining.
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