A component of a hot runner system.
The sprues from the hot runner drop through the cavity plate to the parts. Each sprue has a rod that can be moved forward to cut off flow through the sprue. The opening of the sprue is timed to be just after the melt front has passed that location. The lower pressure drop through the hot runner system is passed on to the gate. The results is lower filling pressures and reduction in the number of weld lines in the plastic part.
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