Triple layer plastic coating process

摘要

A process for triple layer coating of a hollow metal article involves application, onto the cleaned and heated article, of a base layer of pulverulent epoxy resin, a sprayed polymeric adhesive powder layer and then an external cover layer of polyethylene powder, followed by cooling to room temp. The novelty is that the article is a tubular part and is (a) heated to 200-270 (pref. 220-250) deg C before coating and (b) transported continuously in one direction while being screened against radiant heat loss during the heating and coating. Also claimed is an installation for carrying out the above process.