PCE-CPT 20 Cupping Tester 
For coating flexibility and adhesion testing in accordance with ISO 1520
 
CPT 20 is a cupping tester, or surface coating flexibility testing device, used for testing the formability, ductility, adhesion and elongation of paints, lacquers, varnishes, powder and protective coatings on sheet metal. Used in manufacturing production, paint shop and quality control applications, the CPT 20 cupping tester aids in determining coating strength, durability and elasticity.

A mandatory test in Qualicoat and QIB accredited quality control laboratories, a cupping test, also referred to as an Erichsen test or dent test, uses a spherical punch to deform a sample. This deformation results in a cup-like bulge. When using the CPT 20 to perform a cupping test in accordance with the ISO 1520 standard, the sample should be placed coating side up so that the 20 mm spherical punch presses against the uncoated underside of the metal sheet. The cupping test is terminated when small cracks and/or detachments are observed on the bulged part of the sample. The CPT 20 cupping tester's easy-to-read display shows the bulge deformation distances that can be used to determine the coating's flexibility rating.