Loss of Straight Metalworking Fluid Samples From Evaporation During Sampling and Desiccation

Abstract

Straight metalworking fluids (MWFs) were used to evaluate the potential for the loss of MWF mass from filters. Two methods were used to study the stability of MWF mass on filter media. The first was to spike known amounts of MWF onto polyvinyl chloride (PVC) filters, store the filters over silica gel desiccant, and take repeated gravimetric measurements of the filters at intervals of 1, 2, and 3 days. An MWF aerosol mist was generated in a test chamber and collected on PVC filters for the second experimental method. Additional clean air was drawn through a subset of filters (range 0.02–0.48 m3), which were then stored over silica gel prior to weighing. Losses due to desiccation were found in filters that had not been exposed to airflow, as well as for filters after aspiration. The losses occurring in spiked filters (range of mean 2.6–15.2%) were higher than those in collected filters (range 0.7–8.1%). The MWF aerosol mass collected on PVC filters decreased with the increasing volume of clean air passing t...