STARgate HRS expands material and application range

Oerlikon HRSflow has expanded the application range of its STARgate HRS hot-runner technology, which uses a diaphragm-based gate shut-off system to control melt flow into the mold cavity. Previously focused on packaging applications using polypropylene and recycled polypropylene, the pin-less valve gate solution is now also suitable for processing PMMA, ABS, PS, HDPE, LDPE and filled polymers. This broadens its potential use across additional applications and market segments. According to the company, the technology can be used to produce components weighing from 40 g to 2.5 kg.

The diaphragm concept is designed to improve cooling performance compared with conventional solutions. Oerlikon HRSflow reports that it can reduce cycle times by up to 20%, thereby increasing productivity. The nozzle has a free-flow design intended to maintain a consistent melt velocity, smooth the flow of plastics and minimize stagnation areas. These characteristics facilitate faster color changes and can reduce scrap rates.

Part weight and mold dimensions

Trials at the Oerlikon HRSflow R&D Technical Center indicate that the STARgate HRS technology can enable part weight reductions of up to 17%. More efficient and uniform cavity filling, combined with optimized application engineering, mold design and injection molding machine settings, allows wall thickness to be reduced and lighter components to be produced.

The system does not require the installation space for actuators that, in conventional valve gate systems, are typically arranged axially above the valve pins. This enables a reduction in the tool stack height. The pin-less configuration also permits smaller nozzle diameters and smaller mold pockets, resulting in a more compact hot-runner solution.

Production trial at Flow Beyond 2026

Oerlikon HRSflow demonstrated STARgate HRS during Flow Beyond 2026, an international summit held in Italy in September. A live production trial involved the injection molding of a thin-wall, 1.5-liter bucket from recycled polypropylene. The component was manufactured in a two-cavity mold developed by Inmold Group.

The bucket weighed 41 g and was produced with a cycle time of 4.7 seconds, without using a take-out plate. According to the information presented, the trial achieved zero stringing and maintained the required part quality. The result was based on the combined setup of the injection molding machine, mold and hot-runner system equipped with STARgate HRS technology.

Engel, Guztech Polymers and Inmold Group participated as project partners. The case study showed how matching the injection molding machine, mold design and hot-runner system can support productivity and process reliability while maintaining product quality.