Abstract: A mold, adapted for resin transfer molding of composite articles, that has a seal for maintaining a vacuum resulting in denser composite parts. A mold body has at least two openings including an opening for removing the article therethrough. There are at least two mold closures adapted for closing the openings and two of the mold closures are in mutual contact within the interior of the mold. A seal is disposed between each closure and the mold body for sealing each mold closure to the mold body to continuously seal only a single surface. The mold has an improved seal for initiating and maintaining a vacuum thus reducing part porosity.

Abstract: An apparatus for molding hollow composite articles having a plurality of internal webs. A mandrel assembly apparatus includes slidable sidewall members, an inflatable pressure membrane surrounding the length of the slidable sidewall members and actuator means mounted on the interior of the sidewall members for lateral displacement thereof together with the inflatable membrane. Adjacent mandrel assemblies accurately position the internal webs of the composite article mechanically, while the inflatable membranes serve to compact the web laminates. The expandable sidewall members also prevent bridging or tearing of the pressure membrane associated with the formation of inner corner radii.