Proficiency testing of used cold rolling emulsion and fresh oil concentrate

Anders Janols

In November 2009 eight laboratories from four European countries carried out a proficiency test on used cold rolling mill emulsion and fresh oil concentrate used to make up this emulsion. One main purpose of this initiative was to verify the results regarding the suitablilty for performing proficiency testings with such emulsions achieved from two minor Round Robins among four Nordic labs and also a methods study made by SSAB to investigate the impact on analysis results of longer times for transport and the recommended routines for preparing the samples before analysis work.

An important objective was also to gain knowledge of distribution of results between laboratories and methods, in case the proficiency tests on these types of samples were assessed reliable.