Birmingham-based GB Precision (www.gbprecision.co.uk) provides complex bespoke solutions — including mould tools, components and sub-assemblies — to customers in demanding sectors such as medical and pharmaceutical packaging, aerospace and F1.

One recent challenge was to provide a rapid-cycle multi-impression medical-packaging mould tool where the moulding material — a high-performance engineering polymer — had a tendency to ‘string’ during the moulding process.

The customer specified the use of a hot-runner system for the tool, but as GB Precision director Paul Turner observes, “there are hot-runner systems and hot-runner systems. The original specification assumed quite a simple system that would have been adequate for a less challenging application but would in this case have resulted in a narrower moulding window due to the nature of the material.”

GB Precision was able to convince the customer that incorporating a gated hot-runner system would allow the tool design to be optimised with regard to filling and cavity orientation, and thereby reduce the cycle time.

In addition, the moulding window would be substantially increased and material wastage would be reduced.

“By providing our engineering expertise at the tool design stage, we were able to give the customer long-term benefits in his tool’s productivity.

“We were able to show that the initial additional cost of incorporating the more-complex valve gated hot-runner system would be quickly outweighed by savings in accurate mould control, setting optimisation and waste reduction.”