Some of the products of asbestos which are manufactured are discussed below.
1. Asbestos Boards
Asbestos fibres and Portland cement are mixed and moulded under hydraulic pressures. These are available in board and sheet forms. Some of the commercial forms are claddings, roofing and decking units.
Asbestos boards are available in natural mottled grey colour and pigmented boards are also marketed. Boards are dense and rigid but workable easily using carpenter’s tools. These boards can withstand temperatures up to 540°C.
Asbestos boards are marketed in two sizes, viz., Class A: thickness = 6.5 mm and width = 1.2 mm; Class B: thickness = 5.0 mm and width = 1.2 mm.
Asbestos boards are economical and completely incombustible. They can take up paints of any shade economically. These are easily workable and durable.
2. Asbestos Sheets
Asbestos sheets are flat and are classified as compressed and uncompressed. Compressed sheets are of minimum thickness unit which can withstand bending stress of 22 N/mm2 with a density of 1600 kg/m3, whereas uncompressed units can withstand a bending stress of 16 N/mm2 with a density of 1200 kg/m3. Corrugated types of sheets are with thickness varying from 4.76 to 6.35 mm and the corrugation has a pitch of 10 cm and the weight being 145 N/m2.
Asbestos sheets are used for wall-lining, wall-panelling, partitions, side-cladding and false-ceilings. Also used for wardrobes, cupboards and kitchen-pantry shelves. Blackboards, hoardings, signboards, window panes and door panels are also of asbestos sheets.
3. Asbestos Cement Pipes
These pipes are made using 15–20% of asbestos fibres, 80–85% of cement and water. Pipes of different sizes, bands, functions, taper pipes, shoes, etc., are also manufactured to the required shape and size. They can be easily cut and need no paint to maintain.
These pipes claim several advantages because of its adaptability, easy installation, and are light, strong and can withstand normal handling.
Asbestos cement pipes are used as rain water pipes, valley gutters, soil waste and ventilating pipes, half-round gutters, etc.
4. Asbestos Paint
It is prepared by the addition of finely ground asbestos to an oil paint or distemper. It is highly fire resistant, heat and sound insulation. It is vermin-proof and prevents corrosion of metals.
5. Asbestos Fibres
Asbestos is also available in fibre form in the market. These fibres have adequate strength and flexibility and are used in making conveyor belts, boiler insulation, brake lining, etc.
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