Facts about the ASTM D6450 Standard Test Method
The ASTM D6450 test method is used for Flash Point by Continuously Closed Cup (CCCFP) Tester. A Continuously Closed Cup operation is based on an apparatus with a lid of solid brass and electrically controlled temperature. Two sensors measure the temperature of the specimen and the lid, complementary to that, two electrically insulated pins for a high voltage arc and a connecting tube for the pressure monitoring and the air introduction are incorporated in the lid. The chamber temperature is electrically controlled by associated equipment, and also a digital readout of the specimen is provided. ASTM D6450 round robin test results have shown a significant bias compared to the referenced ASTM D93 method. Based on this insight the more elaborated ASTM D7094 method was developed.
With this test method the determination of the flash point of fuel oils, lube oils, solvents, and other liquids is covered. ASTM D6450 measures the tendency of the test specimen to form a flammable mixture with air under controlled laboratory conditions. (Andreas Schwarzmann, R&D)
When measuring with ASTM D6450, the test specimen should ideally flash when the hot flame of the ignited vapor causes an instantaneous pressure increase of at least 20 kPa inside the closed measuring chamber. An amount of 1 ± 0.1 mL test specimen is introduced into the sample cup. At that point both specimen and cup are at a temperature at least 18°C below the expected Flash Point, with additional cooling if necessary. After that the cup is raised and pressed onto the lid of specified dimensions where it forms the continously closed but unsealed test chamber with an overall volume of 4.0 ± 0.2 mL.