Depending on the voltage level, high-tension insulators are often several meters long. In the injection moulding process they are usually produced by applying the "Step-Moulding-Method". However, with the number of steps being increased, the total cycle time rises as well. If the insulators are manually transferred, there will be the risk of an increased reject rate as a result of an operating error.
Cost-saving solutions in the process technology of DESMA
On the basis of a D 968.560 ZO BENCHMARK 750 DESMA developed a special machine which enables the injection moulding of 1,500 mm long articles in one piece by means of mould carrier platens lengthened to 1,700 mm. So the number of steps could be more than halved. The new D 968.700 T has been recently added for article lengths of up to 1,700 mm.
This special machine can be optionally fitted with a LSR injection unit which makes a maximum injection volume of 11,000 cm³ possible. Due to the fact that that liquid silicone is being applied, the injection unit is sufficiently dimensioned with a pressure of 1,000 bar. The injection mould with quickly changeable inserts was developed and produced by the DESMA mould shop. Compared to conventional injection units for customary elastomers, clear cost benefits can be achieved.