Multistation forPVC cones
The Roto LOP 8000/300/4 injection machine with turntable recently supplied by Presma to a German road signage producer is equipped with 4 stations with vertical mould opening and horizontal injection units. It produces PVC cones to a height of one metre with reflective film inserted into the mould prior to injection. The cones have to be injected from the base instead of from the point, as is the usual method, and from the top down to facilitate mould filling without damaging the insert.
To ensure good quality of the melt and prevent scorching, the plasticizing chamber features oil-regulated temperature control, and the injection phase is controlled in a closed loop. The hydraulically controlled shut-off nozzle optimizes rotation times of the mould table and material purging. The four stations ensure optimum cooling of the moulded article and the upward opening of the upper mould half with a 1,100 mm stroke makes it possible to extract the article in an "open sky" configuration, with a sideways shift of the lower mould half.