| 摘要 |
<p>The invention concerns a method and apparatus for injection moulding elongated plastics articles, such as pipes, in welded-together units. The process comprises the steps of (i) providing a mould having an open end closed by one or more gates, an inner mandrel within the mould and defining between its outer surface and the inner surface of the mould the shape of the article to be moulded; (ii) injecting molten plastics material into the space between the mould and the inner mandrel; (iii) moving the newly moulded unit of hollow plastics article at least partially onto a mandrel which was exterior of the gates of the mould when the molten plastics material was being injected, with the rear end of the unit of the article in a position in the mould for another unit of the hollow plastics article to be welded thereto as it is formed in the mould during the next moulding step; (iv) allowing the formed unit of the hollow plastics article to cool outside the mould; and (v) repeating steps (ii), (iii) and (iv) until the desired length of hollow plastics article has been formed.</p> |
