Multistage process for producing hollow plastic articles from half shells

摘要

The present invention relates to a multistage process for producing hollow plastic articles, encompassing the following steps:
a) producing a tubular plastic parison by means of extrusion or coextrusion;
b) cutting open the plastic parison to produce two planar-surface parts by separating the plastic melt with the aid of flow dividers arranged in the interior of the blow molding head;
c) molding the planar-surface parts in two mold halves to give half shells (7), where a removable intermediate frame (8) separates the mold halves from one another at least along the peripheral edges, so that the semifinished products/half shells are not in contact with one another;
d) opening the mold halves and removing the intermediate frame (8);
e) closing the mold halves, with the result that the half shells (7) come into contact with one another along a peripheral rim; and
f) bonding the half shells (7) to give a hollow article.