Comparison of mist generation rates for micro-lubrication and flood application of cutting fluids during milling and drilling.
Gressel-M; Shulman-S; McClure-T; Adams-R; Gugger-M
American Industrial Hygiene Conference and Exposition, June 2-7, 2001, New Orleans, Louisiana. Fairfax, VA: American Industrial Hygiene Association, 2001 Jun; :37
While cutting fluids have been used since the mid-1800's, their use and formulation have changed dramatically over the years, for both performance and health and safety reasons. In addition to the potential occupational hazards associated with cutting fluids, disposal of the used cutting fluids is also a concern to many machining operations. Microlubrication, also known as near-dry and semi-dry machining, is one approach to reducing the volume of cutting fluids used. More traditional approaches to fluid application have been to flood the part and tool with fluid. Micro-lubrication provides the machining process with a limited amount of cutting fluid as a mist, at flow rates that are orders of magnitude lower than for flooding. One question surrounding micro-lubrication is the impact on occupational exposures to the cutting fluid mist. The primary study objective was to compare the respirable aerosol generation rate of cutting fluids from microlubrication and flood application under standardized testing conditions. Two machining processes were studied, milling and drilling, with five different cutting fluids, all soluble oils. Cutting fluid mist was monitored by an Aerodynamic Particle SizerŪ sampling from the exhaust duct of the machining center's enclosure. Particle sizes 10 mm and smaller were used to calculate the concentrations and mist generation rates. When compared to flood application, micro-lubrication resulted in 16 to 180 times the mist generation for drilling and 4.3 to 5.3 times the rate for milling, depending upon the cutting fluid. These results suggest that mist collection systems are more critical for micro-lubrication than with flood application. In addition, these data also suggest that modification of the micro-lubrication application equipment should be explored to increase the size of the mist applied to the machining interface. Such modifications may lead to reduced mist generation rates for micro-lubrication.
Fluid-mechanics; Hazards; Metalworking-fluids; Machine-operators; Machine-tools; Lubricants; Exposure-levels; Respiratory-irritants; Respiration; Respirable-dust; Aerosols; Milling-industry; Oils; Particulate-dust; Particulates; Aerosols; Aerosol-particles
American Industrial Hygiene Conference and Exposition, June 2-7, 2001, New Orleans, Louisiana