CLA 5 - Preventing Bitumen Surface Skin
ASTM D92 Appendix X1 describes a technique to prevent the surface skin formation when testing the flash point of asphalts with an open cup flash point tester like Anton Paar’s CLA 5.
The automatic Cleveland open-cup (COC) measures and describes the properties of a sample in response to heat and a test flame under controlled conditions. The flash point measures the tendency to form a flammable mixture with air while the fire point indicates the tendency of sustained burning.
The CLA 5 is suitable for flash and fire point applications of lubricants or bituminous material. It is an open-cup determination for expected flash and fire points in the range of 79 °C to 400 °C (175 °F to 752 °F).
Asphalt and bitumen tend to form a surface skin when heated up. When a surface skin is present, the flash point detection will fail, because the flammable vapors cannot evaporate from the sample and therefore cannot be ignited by the test flame.
Get the document
To receive this document please enter your email below.