Method and apparatus for forming composite material articles

摘要

A ply (100) of fiber reinforced composite material is laid onto a mandrel (30) having a vacuum ported upper surface with a generally U-shaped cross section. Ply (100) is laid onto the top web (32) of mandrel (30), with its side edges being laid in a cantilevered fashion. A flexible bag (20) is inflated into a stretched condition and lowered over mandrel (30). Bag (20) rolls over mandrel (30) to form play (100) down over mandrel (30). As bag (20) rolls over mandrel (30), it folds ply (100) along two contoured bend lines between the web (32) and flanges (34, 36) of mandrel (30) and simultaneously restrains ply (100) from folding along a straight line. Bag (20) engages a seal (38) carried by mandrel (30). A vacuum is applied through mandrel (30) to evacuate the area between bag (20) and mandrel (30) within seal (38), to compact ply ( 100). Each ply of composite material is formed and compacted before laying another ply.