| 摘要 |
According to a first aspect of the invention, there is provided a process for manufacturing a spiral concentrator unit including the steps of providing a first mould (10) for moulding an inner, slurry bearing polyurethane layer; providing a fibreglass backing layer (13), located so as to create an enclosed cavity (12) between the first mould and the backing layer; and filling the mould cavity (12) with polyurethane, allowing the polyurethane to cure and bond with the backing layer (13) so as to produce a spiral trough with a uniform, high wear resistant inner layer of polyrethane and a relatively cheaper fibreglass backing layer. |
