GB862094A - Improvements in or relating to the construction of water boxes for heat exchangers - Google Patents

Abstract

862,094. Laminates. MENDIP (CHEMICAL ENGINEERING) Ltd. July 24, 1959 [April 26, 1958], No. 13315/58. Class 140. [Also in Group XIII] A heat-exchanger water box or header (see Group XIII) is made by applying successive layers of fibre reinforced synthetic resin to a mould each layer-being separately polymerized or all of the layers being polymerized simultaneously. In forming the box, an initial layer (layer B), of polyamide, polyester or polyacrylic fibre is moulded to the required inside shape of the box, and then a synthetic resin such as a polyester or epoxide is applied in the form of a viscous liquid and worked into the fibre layer, the resin containing a suitable catalyst or hardener such that it will harden only after several days at room temperature, Reinforcement in the form of a prefabricated steel network R is then pressed into the resin before the latter hardens and thereafter a final layer of (layer C) of synthetic resin reinforced by glass, polyamide, polyester, polyacrylic or other fibres is applied. Layers B and C may contain a filler such as calcium carbonate to modify the characteristics of the material, layer C containing more filler than layer B, this being said to obviate excessive stresses which would otherwise arise due to unequal contraction of layers B and C. A condensed silica may be added to the resin to facilitate application. Each of the layers B and C may be formed by several applications of the resin. The steel network R may be omitted.