Method and apparatus for coating the interior surface of hollow tubular articles.

摘要

A method and apparatus for spraying a solid particulate powder onto the interior surface of tubular articles (3) by intermittently pumping the powder from a fluidized bed of powder through a powder supply line containing an intermittently operated venturi pump and air amplifier, as well as a pair of constantly operated air diffusers and an electrostatic charging apparatus. A powder collection shroud (6, 23) adjacent at least one open end of the tubular article (3) has a carefully regulated vacuum applied thereto in order to collect oversprayed powders.