Pensky-Martens Closed Cup Test Procedure

Summary

The Pensky-Martens Closed Cup Tester can be used to determine the flashpoint of a petroleum product in the temperature range 40-360°C. The procedure used to determine the flashpoint is dependent on the petroleum product. Procedure A applies to distillate fuels such as diesel or kerosene, while procedure B is applicable to residual fuel oils, petroleum liquids that form a surface film under test conditions and used lubricating oils amongst others. The sample is contained in a brass test cup which is placed inside the apparatus and fitted with a testcover. The sample contained in the test cup is heated and stirred simultaneously. An external ignition source is periodically directed into the test cup (this momentarily interrupts the stirring). This is done until a flash is observed (meaning the sample has reached its flashpoint).