7 aspects to pay attention to when designing LSR liquid silicone injection molds

The structure of thermoset liquid silicone rubber (LSR) injection molds is generally similar to that of molds used for thermoplastic compounds, but there are several significant differences. For example, LSR compounds generally have a low viscosity and therefore very short filling times, even at very low injection pressures. To avoid air trapping, it is essential to have a good air venting device in the mold. In addition, LSR compounds do not shrink as much as thermoplastic compounds in the mold; they tend to expand when hot and shrink slightly when cold. As a result, the product does not always remain on the convex side of the mold as expected but is retained in the cavity with a larger surface area.

Zetarmold ∙

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∙ 1y ago