Bonding fiberglass-reinforced plastics

The tubular reverse osmosis device is shown in Figure 4.10. The tube serves as the pressure vessel and the membrane is installed inside the tube. Tubes with inside diameters of % and 1 inch have been used. Uniformly porous fiberglass reinforced plastic tubes have been used and nonporous but perforated copper, stainless steel and fiberglass tubes have also been successfully used. The membrane can be bonded to the tube in which case it is cast in situ or the membrane can be loose. The loose membrane is cast in sheet form and a cylindrical section is formed and placed in the tube. Packing densities for the Vi-inch diameter tube are about 100 square feet per cubic foot and about 50 square feet per cubic foot for the 1-inch diameter tube. 

Fiberglass-Reinforced Plastics. To obtain high-quality pipe connections, the surfaces to be joined must be roughened and the pipes carefully tapered. Polyester adhesives or thermosetting epoxy resin adhesives are best suited for bonding. A pressure of 50 -100 N/cm is applied to the joined surfaces. 

The relative elongation of the metal on bonding of the biplates to the extent that the fibers of the fiberglass break and wrinkles and folds appear in the external layer of the glass-reinforced plastic amoimts to 0.19-0.22%. 

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