Can High Clamp Tonnage Cause Flash?

In a recent seminar, I received this interesting question…

Can high clamp tonnage actually cause flash?
My Response
Yes, it actually can. High Clamp Tonnage can block the vents, causing gases to become trapped in the mold during 1st stage injection. Although, these gasses most often heat and cause burning or short shots… these gasses can also force the parting line to open allowing the gases and some polymer to escape.
This rare flash resulting from high clamp tonnage tends to be very thin and wispy since it often tightly clamped immediately after it is formed. Often, this flash remains with the mold and builds up on the parting line.
Additional Thoughts
Excessive clamp tonnage is never a good practice as it will often cause damage to the vents, parting line, and may even stress the mold components.

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