Abstract: A method of molding a high density composite article which, when completed, has opposed outer skins of fiber-reinforced plastics material and polymer mortar core between the skins. The method is performed by (a) providing an openable mold defining a mold cavity and an injection port through which polymer mortar may be introduced into the cavity; (b) opening the mold and placing within the cavity respective layers of fiber reinforcement to form the opposed outer skins; (c) closing the mold and injecting polymer mortar consisting of a resinous material loaded with high density particulate aggregate through the injection port into the cavity, between the layers of fiber reinforcement placed therein; and (d) applying sufficient pressure to the injected polymer mortar to ensure resin is separated from the polymer mortar and penetrates the said layers.

Abstract: A method of moulding a high density composite article which, when completed, has opposed outer skins of fibre-reinforced plastics material and polymer mortar core between the skins. The method is performed by (a) providing an openable mould defining a mould cavity and an injection port through which polymer mortar may be introduced into the cavity; (b) opening the mould and placing within the cavity respective layers of fibre reinforcement to form the opposed outer skins; (c) closing the mould and injecting polymer mortar consisting of a resinous material loaded with high density particulate aggregate through the injection port into the cavity, between the layers of fibre reinforcement placed therein; and (d) applying sufficient pressure to the injected polymer mortar to ensure resin is separated from the polymer mortar and penetrates the said layers.

Abstract: A pipe construction system which utilises a multiplicity of arcuate pipe segments 11, 12 to form a pipe section 10 and which sections are assembled together to form a length of pipe. Each segment 11, 12 has two longitudinal edges 13 of increased radial thickness and having a groove 14 formed in the circumferential direction whereby an interlocking and sealing member 15 may be located in the aligned grooves 14 of two adjacent segments 11, 12. One end of a pipe section 10 assembled from the segments defines a socket 22 for receiving a spigot 23 defined at the other end of a like section. The spigot end of each segment has a pocket 25 formed along said edge 13 but within the thickness of the major area of the segment, which pocket 25 mates with a corresponding pocket 25 of an adjacent segment whereby sealant may be disposed in the mating pockets.