BGD 568—T-Bend Tester is designed to evaluate the flexibility and adhesion of an organic coating on a metallic substrate by observing the cracking or loss of adhesion when a coated test panel is bent.This method can be used to confirm whether paints, varnishes or related products meet a given test requirement in a pass/fail test, or to determine the minimum bending diameter at which cracking does not occur.

Coated panels are bent back on themselves to 180º, with the coated surface on the outside of the bend, at progressively less severe radii of curvature, the radii of curvature being defined by spacers or mandrels. After bending, each panel is examined with a magnifying glass for cracking of the coating and by a tape pull-off test for loss of adhesion of the coating. The minimum diameter to which the test panel can be bent without cracking or loss of adhesion,i.e.when failures on longer occur, is taken as the T-bend rating.

It conforms with DIN EN ISO 17132, ASTM D 4145 and EN 13523-7 《Paints and varnishes – T-bend test》 “Folding method”