25) Which metal is used for coating vessels in food industry?

26) What is the name of method of plastic coating that the heated part kept in a bed of powdered plastic resin held in suspension by air?

27) Which surface preparation method the solvent white sprit, carbon tetra chloride, trichloroethylene is used?

28) What is the name of surface preparation method?

29) Which method of surface preparation is used for the heavily rusted steel work?