abstract |
A method for the manufacture of panel heat exchangers from thermoplastic polyamides. At least one sheet is coated with a coating that facilitates bonding of the polymer to itself under the influence of heat. Two sheets, at least one of which has been coated, are placed between moulds in a press. At least one of the moulds has grooves corresponding to the pattern of fluid flow passages to provided in the panel heat exchanger. The moulds are heated and an inert gas e.g. nitrogen, is applied and passed through the fluid flow passages, to assist in the formation of the passages and to remove any voltatile material from the coating. The preferred coating is benzyl alcohol, phenol and polyamide. The heat exchangers may be used in a variety of end-uses, especially in automotive end-uses. |