PIPE FORMING APPARATUS FOR VOLUME OF PLASTIC ALONG THE PIPE WALL

摘要

Apparatus for forming continuous products as an extruder die (21) with a supply channel which terminates with a channel mouth feeding plastic to a moving mold tunnel (23). The mold tunnel (23) comprises mold blocks (25, 27) of different mold block shapes which move past the channel mouth (31, 39) to form the wall of the product with a varying configuration. The channel mouth (31, 39) has an adjustable mouth gap which automatically adjusts in gap size according to which one of the mold block (25, 27) shapes is moving past the channel mouth (31, 39) to adjust plastic flow through the channel mouth so as to affect changes in thickness of the plastic along the product wall.