sprue

Sprue refers to the small short passage between end position of runner and cavity. Its function is speeding up the feedstock solution injected into mold cavity in order to fill cavity. And through the gate would add some feed solutions to compensate for the shrinkage in production. Sprue has various types, including straight gate (center), side gate (rectangular gate) superimposed gate, fan gate, film gate, ear shape gate, disc gate, auxiliary wheel type gate, point gate, sub-gate etc.

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