Sherwin Inc. manufacturers industry leading liquid penetrant system monitoring products, and the PSM-5 is one of the most popular items.
The PSM-5 test panel is stainless steel, 0.090" thick and measuring 4 x 6 inches. A chrome plated strip runs the length of one side of the panel. Five crack centers are evenly spaced in the chrome plating in order of magnitude/size; the largest is readily visible with low sensitivity liquid penetrants, while the smallest is difficult to observe even with highly sensitive materials. Adjacent to the chrome plated section is a grit blasted area of "medium roughness", to judge the wash characteristics of the penetrant.
The PSM-5 Panel comes in two versions. Both versions are manufactured to Pratt-Whitney P/N TAM 146040 specifications.
Grit Blasted Type - has a chrome strip which has been lightly grit blasted in order to dull the surface
Polished Type - the chrome plated strip on this version is not grit blasted
Sherwin Incorporated is an authorized manufacturer of TAM 146040 panels. PSM-5 Panel processing meets MIL-STD-6866 and ASTM E-1417 requirements for daily system check.