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Ali Hamza
Ali Hamza
Mechanical
20 Jan 2019

What is the surface Application of paints on Metals??

Surface Application on metal:

New Iron Work:

The surface should be free from scales, rust and grease. Scales and rust are cleaned by hardwire brush. Grease is removed by using petroleum or by hot alkaline solution of Na2CO3 orNaOH, benzene, and limewater. A priming coat of red lead with barytes(BaSO4) and raw linseed oilis then applied over the prepared surface. After drying of the priming coat, one or moreundercoatswith desired paint are applied. The second coat is given only after the first coathas dried. The finishing coat is applied carefully to produce a smooth fine surface.

Old Iron Work

The surface is prepared by scraping properly all the scales and rust with emery paper. Thegreasy substances are removed with lime water. The old paint may be burned with a blowlamp or by suitable solvents. After this the surface is brushed with hot linseed oil and paintedas for new iron work.