This standard sized item prevents the ejector plates from retracting completely so it does not rest against the clamping plate. This avoids plate cocking and rust formation between the two plates during storage. Stop pins are not always used in mold design.
Typically four or more stop pins are used between the rear clamping plate and the ejector plate. Most are on the clamping plates and are typically located in the same position as the ejector return pins.
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