An Experimental Investigation of Cutting Fluid Mist Formation Via Atomization in the Turning Process
 
 
 

Kenneth L. Gunter | MS | 1999

Cutting fluid mist that is formed during machining operations represents a significant waste stream and potential health hazard. Existing control strategies, including machine enclosures, mist collectors, mist suppressants, and dry machining, are not totally effective in preventing cutting fluid mist exposure and may result in increased manufacturing costs. An alternative strategy is to modify the machining process itself so as to reduce or eliminate the formation of mist droplets. Such a strategy requires a fundamental understanding of the underlying process conditions that influence mist formation, which up to this point have not been well understood or widely investigated.
 

In this work, an experimental investigation is conducted of the underlying process conditions influencing cutting fluid mist formation via atomization in the turning process. Design of Experiments methods are used to determine the statistical significance of several variables on mist mass concentration and size distribution, including spindle speed, workpiece diameter, sampling location, and oil concentration. It is found that increasing spindle speed has a dominant effect on the PM10, PM2.5, and PM1.0 mist mass concentration.
 

Spindle speed is also found to significantly affect the number of super and submicron particles that are generated. In addition, the interaction of spindle speed with other variables (e.g., workpiece diameter, sampling location) is shown to have a significant effect on other mist distribution statistics, such as mean diameter and standard deviation. Responses tend to be approximately equal for high spindle speed but exhibit more variation at the low level.

Due to growing concerns that the smallest airborne particles pose the greatest health threat, the effects of process conditions on the formation of submicron particles is also investigated. It is observed that the smallest ambient particles are effectively removed by the addition of a high concentration of larger mist droplets. This fact may prove to be useful in the implementation of improved mist control strategies.

If you have any comments or suggestions please e-mail jwsuther@mtu.edu.