Structural Foam Molding is a low-pressure injection molding process that is capable of producing very large structural parts. The molten plastic material is injected into a mold after being mixed with a blowing agent or high-pressure gas. This produces bubbles in the plastic causing it to foam. The foam retains the properties of the plastic but weighs less because of reduced density.

Process Characteristics
Part Cost - moderate Tooling cost - moderate - Low pressure allows use of less expensive tooling Production rate - moderate to high Multiple nozzles are possible in a single part to allow large surface areas. Parts have a swirl pattern so they must be finished for cosmetic purposes Parts can be molded with thick cross sections Sink marks are reduced Process can produce parts up to 100 lbs. and 12 ft. x 10 ft. in area
Examples
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