Polímeros: Ciência e Tecnologia
Polímeros: Ciência e Tecnologia
Original Article

A methodology for determination the inlet velocity in injection molding simulations

Diego Alves de Miranda; Willian Kévin Rauber; Miguel Vaz Jr.; Paulo Sergio Berving Zdanski

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The inlet velocity of thermoplastic in injection molds plays a crucial role in obtaining high-quality polymer parts and the final performance of the product. It is known that the way the polymer is injected into the mold can directly affect important properties, such as the distribution of internal stresses, the cooling rate and the formation of surface defects. However, there are injection molding machines that only control injection pressure and dosage, making it difficult to obtain the gate inlet velocity into the mold cavity. Besides, some molds have many injection channels as well as complex inlet geometries, which make a challenging task to identify the inlet velocity. This study presents numerical and experimental approaches on how to determine the entry velocity in thermoplastic injection molds. The main results showed that these methods are highly efficient and contribute to identifying the gate inlet velocity with good accuracy.




inlet velocity, injection molds, numerical/experimental methodologies


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