摘要 |
<p>A thickened end is formed on a plastics pipe by heating the pipe end over a predetermined length and axially compressing the heated length in a mould cavity which is longer than the heated length. During an initial phase of the compression, the heated length is thickened and during a subsequent phase the adjacent section of the unheated remainder of the pipe is heated by conduction from the heated length. Thickened conditions are arranged so that the ultimate thickened length of pipe is slightly less than the length of the cavity.</p> |