简介:Electrostatic, rotating bell (ESRB) application is one of the most important coating application techniques
for industries with demanding specifications for optical attractiveness of coatings, such as automotive. The
E简介:Electrostatic, rotating bell (ESRB) application is one of the most important coating application techniques
for industries with demanding specifications for optical attractiveness of coatings, such as automotive. The
ESRB process involves production of droplets using a high-speed rotating bell, which are subsequently
transported to the substrate being coated via shaping air [1-3]. An electrical potential is applied between the
bell and the substrate which further helps droplet atomization and transport. This research investigates the
effects of inertia, centrifugal force, drag force, and electrostatic force on the atomization mechanism and
particle size distribution using an automotive OEM base coat formulation. Coating flow rate (CFR), shaping
air flow rate (SAFR), bell speed (BS), and electrostatic potential (EP) were used as primary parameters to
create various atomization conditions and particle size distributions. The atomization mechanism, ligament
formation, and particle size distribution were measured using high-speed laser shadowography and image
processing. The effects of governing forces and particle size generated on efficiency of droplet transfer to the
substrate and optical appearance of the coatings were studied to generate operating windows for optimum
process efficiency and appearance.详细>