THE FLUIDISED BED COATING PROCESS

During recent years the use of the fluidised‐bed method of applying plastics coatings to metals has increased considerably. The plastic is in the form of a powder kept in a suspended or ‘fluidised’ state by injecting air into the bed of powder. After cleaning, the article is preheated to a temperature above the melting point of the particular powder being used, and then dipped into the powder. As the particles of powder come into contact with it, they adhere to it and flow together to form a continuous protective surface. After removal from the bed the articles may be further heated in order to obtain full cure and improve the surface quality.