Oil composition for use in trace oil supply cutting/grinding work

Abstract

This invention provides an oil composition for cutting and grinding by minimum quantity lubrication system, characterized by comprising an ester oil with a kinematic viscosity of 0.5-20 mm 2 /s at 100° C., and an ester-based polymer with a kinematic viscosity exceeding 20 mm 2 /s at 100° C. and an average molecular weight of 5,000-10,000,000. The oil composition for cutting and grinding by minimum quantity lubrication system according to the invention can achieve an excellent balance between misting property and inhibition of floating mist and ensure that an adequate amount reaches the working section, for cutting and grinding by minimum quantity lubrication system.

1 . (canceled) 
     
     
         2 . A process comprising the steps of:
 cutting and grinding a workpiece by minimum quantity lubrication system with an oil composition;   wherein the oil composition comprises:   an ester of a polyhydric alcohol and a monobasic acid with a kinematic viscosity of 0.2-12 mm 2 /s at 100° C., and   an ester-based polymer with a kinematic viscosity exceeding 20 mm 2 /s to 2,500 mm 2 /s at 100° C. and an average molecular weight of 10,000-300,000;   wherein the content of the ester is 90.00 to 99.99% by mass and the content of the ester-based polymer is 0.01 to 10.00% by mass based on a total amount of the composition.   
     
     
         3 . A minimum quantity lubrication system, comprising:
 a cutting and grinding apparatus cutting and grinding a workpiece;   a lubrication apparatus providing a lubricant oil composition to the cutting and grinding apparatus;   wherein the lubricant oil composition comprises:   an ester of a polyhydric alcohol and a monobasic acid with a kinematic viscosity of 0.2-12 mm 2 /s at 100° C., and   an ester-based polymer with a kinematic viscosity exceeding 20 mm 2 /s to 2,500 mm 2 /s at 100° C. and an average molecular weight of 10,000-300,000;   wherein the content of the ester is 90.00 to 99.99% by mass and the content of the ester-based polymer is 0.01 to 10.00% by mass based on a total amount of the composition.