| 摘要 |
<PICT:0942731/C3/1> In a process for moulding articles of an expanded polymeric material, in which the cooling time of the article in the mould is decreased, polymeric particles containing an expanding agent are partially expanded then crushed while still hot and re-expanded and subsequently moulded into the finished article in a heated mould. Unexpanded particles, from a hopper 23A, are partially expanded in a cylindrical stainless steel expander 10 by steam from a conduit 27A and fed via a shoot 29A to the rollers 37 where they are crushed to 2-2 1/2 times their expanded density. The crushed particles are then partially re-expanded by steam in a cylinder 11 and subsequently fed to a storage unit 12 where the particles are allowed to mature for 6-10 hours during which time particles absorb atmospheric air. The pre-expanded particles are then fed to a heated mould 13 and moulded into the finished article which is removed after it has sufficiently cooled. The crushing rollers are preferably lightweight hollow rolls, e.g. stainless steel pipes. During expansion in the cylinders 0, 11 the particles are agitated to prevent agglomeration by stirrers driven by motors 31A and 31B respectively. The time spent during the expansion in the second cylinder 11 is reduced by the stream of air issuing from the line 35.
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