| 摘要 |
<p>The cast tube (T) is subjected internally in a chill-mould (1) to the uniform spraying of water from 1000 DEG C. approximately to 350 DEG C. approximately. Then it is extracted from the chill-mould and in a furnace is subjected to isothermal bainitisation maintenance, after which it is cooled in the atmosphere to ambient temperature. Without it being necessary to add expensive chilling elements, one thus obtains lightened tubes having very good mechanical properties and the ovalisation of which remains acceptable.</p> |
