AWWA C203-20 pdf download.Coal-Tar Protective Coatings and Linings for Steel Water Pipe
4.3.1 General. This section describes the composition and physical properties of materials to be used for liquid adhesives, coal-tar enamel, innerwraps, outerwraps, and finish coats intended for use in hot-applied coal-tar enamel linings and protective coating systems for steel water pipelines. The liquid adhesive and coal tar shall be provided by the same manufacturer.
4.3.2 Liquid adhesive. Type A (coal-tar), Type B (fast-drying, synthetic), and Type C (two-component heat-curable liquid epoxy) liquid adhesives are covered by this standard. Unless Type A liquid adhesive is specified by the purchaser, Type B or Type C liquid adhesive, which may be employed under all conditions when coal-tar enamel is specified, shall be used. At site locations where air emission regulations may restrict the use of Type A and Type B liquid adhesive, other resin-base liquid adhesives may be used as equivalent to the Type A, B, and C liquid adhesives covered in this standard, provided that when topcoated with the appropriate coal-tar enamel, they meet the performance requirements of Table 1 and are approved by the purchaser. Consult the manufacturer for specific alternative surface preparation and application systems.
4.3.2.1 Type A liquid adhesive. Coal-tar liquid adhesive shall consist only of processed coal-tar pitch and refined coal-tar oils, suitably blended to produce a liquid that may be applied cold by brushing or spraying and that will produce an effective bond between the metal and a subsequent coating of coal-tar enamel.
4.3.2.2 Type B liquid adhesive. Fast-drying synthetic liquid adhesive shall consist of chlorinated rubber, synthetic plasticizer, and solvents. These constituents shall be suitably compounded to produce a liquid that can be readily applied cold by brushing or spraying and that will produce a suitable and effective bond between the metal and a subsequent coating of coal-tar enamel.
4.3.2.3 Type C liquid adhesive. Rapid-curing two-component liquid epoxy system uses the latent heat of the hot enamel to cure the system. The constituents shall be suitably compounded to produce a liquid that can be readily applied at ambient temperatures by brushing or spraying and that will produce a suitable and effective bond between the metal and a subsequent coating of coal-tar enamel.
4.3.2.4 Application properties. The Type A and Type B liquid adhesives shall dry to the touch in accordance with the manufacturer’s recommendations. Type C liquid adhesive shall be applied according to the manufacturer’s recommendations. Type C shall not be allowed to cure or dry prior to the application of hot enamel.AWWA C203-20 pdf download.