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Buderus Manual on Trenchless Installation of Ductile Cast ... - Duktus

Buderus Manual on Trenchless Installation of Ductile Cast ... - Duktus

Buderus Manual on Trenchless Installation of Ductile Cast ... - Duktus

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Properties <strong>of</strong> ductile cast ir<strong>on</strong> pipes<br />

In today‘s typical pipe foundry, the cast ir<strong>on</strong> for producing the pipes is smelted in a cupola<br />

furnace, is adjusted to a preset compositi<strong>on</strong> by tailored metallurgical procedures<br />

and is raised to the requisite casting temperature. This is followed by the treatment<br />

with magnesium to produce ductile cast ir<strong>on</strong> and the melt, having been treated in this<br />

way, is then at <strong>on</strong>ce cast into pipes.<br />

The outcome <strong>of</strong> the developments that took place over the 0 years between 1920<br />

and 1970 was that the tensile strength <strong>of</strong> pipes could be raised and their weight and<br />

wall thickness halved. As development <strong>of</strong> the producti<strong>on</strong> technology has c<strong>on</strong>tinued,<br />

and above all with modern-day systems for c<strong>on</strong>trolling the casting machines, it has<br />

been possible for a c<strong>on</strong>siderable further reducti<strong>on</strong> to be made in the wall thickness <strong>of</strong><br />

the pipes. Account has been taken <strong>of</strong> this in the product standards EN [2.1] and<br />

EN 98 [2.2], where a shift can be seen from classificati<strong>on</strong> by wall thickness to classificati<strong>on</strong><br />

by pressure class.<br />

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