Production of hollow- or coated injection mouldings in simplification of gas internal pressure process

摘要

There manufacture of mouldings with an internal cavity, involves using two different materials and is based on the gas internal pressure method, in which a first medium fills a mould and a second medium is introduced subsequently. In the new method, a core section (5) is first introduced into the mould cavity (1). A moulding compound then fills the remaining space. The core is removed, leaving a space (7) corresponding to its volume. The second medium (e.g. gas) is then injected into the compound at one or more points, displacing the compound to form the internal cavity (8).