Abstract: Apparatus for forming articles, e.g. one-piece pipe insulators, from a longitudinally advancing strip-shaped felt of fibrous material has a housing around tubular inner and outer dies, a gas supply through openings in the outer die for curing the felt as the felt is pulled between the dies from beyond the dies and a transverse cutter for cutting the cured felt to length. To facilitate easy replacement of the outer die, e.g. by another outer die of different transverse size or shape, the housing has openings larger than the cross-section of the outer die for receiving the outer die therethrough, and readily releasable closure plates around the outer die close the housing openings. The outer die may comprise separable sections connected end-to-end.

Abstract: A fibre felt forming die assembly and method employ a mandrel having an external forming surface, an outer die extending around the mandrel and having an internal forming surface spaced from the mandrel external forming surface to define a gap for the advance of a felt therebetween. A heater is provided for heating the mandrel to thereby heat and at least partially cure the felt at and adjacent a surface of the felt facing the mandrel as the felt passes through the gap, and hot gas is then discharged through the entire thickness of the felt to further cure the felt. To counteract deposition of bonding material from the felt on the mandrel, an arrangement is provided for cooling the felt prior to the heating of the felt by the mandrel, so that the felt undergoes a rapid temperature transition.

Abstract: A method for the continuous formation of articles, e.g. one piece pipe insulator sections, from a strip-shaped felt of fibrous material, e.g. glass fibre, containing a hardenable bonding material employs stationary forming surfaces between which the strip is pulled, from beyond the forming surfaces, to deform the strip, which is then cured. The forming surfaces are readily and inexpensively replaceable for forming articles of various shapes and/or sizes.