| 摘要 |
<p>A process for the manufacture of piping from a material having a secondary crystallization phase, such as polybutylene. The extruded piping is laid straight or on a large diameter drum immediately after moulding and remains so until the secondary crystallization phase is substantially complete. This causes the piping to 'memorize' the straight or substantially straight condition, thus allowing it to be coiled for storage without assuming an undesirable curvature.</p> |
