Metalworking machine

Abstract

A metalworking machine includes a tool for machining a workpiece metal and a cooling liquid supply unit for supplying a cooling liquid to a machining portion between the tool and the workpiece metal. The cooling liquid is formed by applying a degassing treatment that removes dissolved gases from the cooling liquid, and a hydrogenation treatment that adds hydrogen to the cooling liquid.

1 . A metalworking machine comprising:
 a tool for machining a workpiece metal;   a supply unit for supplying a cooling liquid to a machining portion between the tool and the workpiece metal; and   a producing unit for producing the cooling liquid by applying a degassing treatment that removes a dissolved gas from the cooling liquid and a hydrogenation treatment that adds hydrogen to the cooling liquid.   
     
     
         2 . The metalworking machine according to  claim 1 , wherein
 the dissolved gas comprises a nitrogen gas and an oxygen gas, and   concentrations of the nitrogen gas and the oxygen gas dissolved in degassed water after the degassing treatment are 1 ppm or less, respectively.   
     
     
         3 . The metalworking machine according to  claim 2 , wherein the concentrations of the nitrogen gas and the oxygen gas after the degassing treatment are 1 ppb or less, respectively. 
     
     
         4 . The metalworking machine according to  claim 1 , wherein the hydrogenation treatment is a treatment that adds the hydrogen in an amount which is less than a saturated solubility of the hydrogen and which reduces an oxidation-reduction potential of the cooling liquid to a numerical value having no oxidizability. 
     
     
         5 . The metalworking machine according to  claim 4 , wherein the hydrogenation treatment is a treatment that adds the hydrogen at 0.6 to 0.8 ppm. 
     
     
         6 . The metalworking machine according to  claim 1 , wherein the cooling liquid is formed by being further subjected to an oil addition treatment that adds degassed mineral oil or degassed oil and fat. 
     
     
         7 . The metalworking machine according to  claim 6 , wherein the oil addition treatment is a treatment that adds the degassed mineral oil or the degassed oil and fat at 5 to 10%.