Do well the needle valve type mold, into the gate generally lower than the product surface, in the absence of phi front by surface without obvious traces of color to identify, use a needle valve type into the gate is to use the gate set, with cooling temperature will be higher than near around some, slightly shiny.
There will also be obvious marks on the valve tip, because the high temperature and the freezing of the inlet will always be more direct than the mold steel.
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