The heated sprue nozzle brings the point of thermal separation to the mold-parting surface and eliminates the major of the sprue excess material. Cycle times decrease up to 40 % and provide better part quality.
- Up to 40% reduced cycle time
- Up to 30% reduced shot size
- Up to 7% increased part weight due to higher microstructure density
- Improves part quality
- Reduces porosity and eliminates costly sprue cone
- Decreases tool costs
- Traditional cold plug nozzles can be replaced by the hotcast sprue nozzle
- Increased design options with new mold design e. g. smaller plate thickness
- Less scrap after electro-plating finishing, e.g. improved surface
- Continuous heating from goose neck to the mold
- Integrates into 50T, 80T and 125T die-casting machines
A sprue is normal with traditional hot-chamber die-casting production process. After casting the melt is freezing inside the long melt supply channels. The added sprue weight and size increases the amount of zinc to be recycled and increases production costs.
The new hotcast Sprue Nozzle is located at the mold-parting surface – like the common cold sprue bushing. Therefore the point of thermal melt separation is moved from injection point to the mold-parting surface, which reduces the sprue to a minimum. The advantages are reduced production material costs, reduced tooling costs and improved cycle times due to faster freezing of the zinc melt. In field production tests cycle times have been improved up to 40 %.
The flow distance from the heated machine nozzle to the mold is an important factor to improve acceptable part quality. The heated hotcast Sprue Nozzle causes a higher melt temperature within the mold versus the traditional cold sprue design. Mold filling can be improved; longer cast distances or thinner cast channel width can be designed with same quality.
Higher flow characteristics results in higher microstructure density. Less porosity and blow holes increase part weight during production. Tests confirm that scrap is significantly reduced with surface sensitive parts. This means increased part yield and reduced scrap rates after finishing processes, (e.g. electro-plating), will improve the bottom line costs.
Moreover, the use of the Sprue Nozzle results in longer life of machine components and tools. With same mold filling process the cast pressure and speed parameters can be reduced without suffering part quality.
hotset has been greatly successful with the development of this sprue nozzle. It is already working at renowned companies:
Dr. Christian Kuwer, Technical Manager of Sieper GmbH in Lüdenscheid, Germany (manufacturer of SIKU toy model cars and WIKING models) has used them and come to the conclusion:
“We have discovered that one of our 'problem tools', with which we were previously only able to produce difficult-to-cast components to an extremely high quality“.
Dr. Kuwer confirms also: “The filling speed and filling pressure can be reduced without any disadvantages to the quality of the component”.