Disk Area Requirements:
The size of the specimen is related to the material. For most hard-made specimens, the specimen size can be a square with a side length of 100 mm (4.0 inches). For soft specimens, the specimen should be round and use a sample holder. If a sample pad is used, the diameter of the sample should be 108 mm (4.25 inches). If the sample pad is not used, the diameter of the sample should be 135 mm (5.25 inches) so that the sample fixing ring can clamp the edge of the specimen.
If the specimen is smaller than the recommended size, you can put 2 to 3 samples on the specimen pad to meet the needs of the test. If the edges of the sample cannot butt or the thickness of the sample is different, the abrasion test results reflected on the edges will be different from the results of other parts of the sample.
The standard thickness is 6.35 mm (0.25 inches). For samples with a thickness of more than 6.35 mm (0.25 inches) and less than 12.7 mm (0.5 inches), the S-21 riser nut needs to be adjusted. Thickness exceeding 12.7 mm (0.5 inches) requires the use of an abrasion bracket arm raising device.