Enamels Glass fibres

Many metal borates find important industrial applications (p. 140) and annual world production exceeds 2.9 million tonnes Turkey 1.2, USA 1.1, Argentina 0.26, the former Soviet Union 0.18, Chile 0.13Mt. Main uses are in glass-fibre and cellular insulation, the manufacture of borosilicate glasses and enamels, and as fire retardants. Sodium perborate (for detergents) is manufactured on a 550 000 tonne pa scale. 

In pipelining, the trend is towards all-welded steel for long lines, and since the wall thickness is less than that of cast iron, protection is the more important. Many types of coating are used, from thick concrete to thin paint films, and each has its own particular suitability, but the majority of pipelines throughout the world today are coated with hot-applied coal tar or petroleum asphalt-base-filled pipeline enamels, into which reinforcing wraps, such as glass fibre are applied. 

In the special case of pipelines operating at relatively high temperatures such as for the transmission of heavy fuel oil at up to 85°C, heat insulation and electrical insulation are provided by up to 50 mm of foam-expanded polyurethane. As a further insurance against penetration of water, and to prevent mechanical damage, outer coatings of polyethylene (5 mm), butyl laminate tape (0-8 mm) or coal-tar enamel reinforced with glass fibre (2-5 mm) have been used. 

Glass fibre reinforced enamels BS 4147 BS 4164 BS SI4 AWWA/ANSI C203 Hot applied in factory and in field by line travel 2-5-6 Asphalts prone to water absorption and root damage. Coal tar resistant to oil products and root damage. Long successful service record, particularly coal tars. Proven under concrete weight coatings. 

Chile 0.13Mt. Main uses are in glass-fibre and cellular insulation, the manufacture of borosilicate glasses and enamels, and as fire retardants. Sodium perborate (for detergents) is manufactured on a 550 000 tonne pa scale. 

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