Water glycol-based hydraulic fluid
The present invention provides a water-glycol hydraulic fluid comprising 0.3-0.6% by mass in total of fatty acid sodium salt and/or fatty acid, and 0.3-0.6% by mass of dimerized fatty acid. The water-glycol hydraulic fluid also comprises 20-60% by mass water, 20-60% by mass glycol, 0.01-0.06% by mass alkali hydroxide compound selected from potassium hydroxide and/or sodium hydroxide, and 1.0-5.0% by mass alkanolamine.
1. A water-glycol hydraulic fluid comprising 20-60% by mass water, 20-60% by mass glycol, 0.01-0.06% by mass alkali hydroxide compound selected from potassium hydroxide and/or sodium hydroxide, 1.0-5.0% by mass alkanolamine, 0.3-0.6% by mass in total of fatty acid sodium salt and/or fatty acid having from 4 to 18 carbon atoms, and 0.3-0.6% by mass of dimerized fatty acid.
2. The water-glycol hydraulic fluid according to claim 1 , wherein the fatty acid sodium salt is sodium laurate having 12 carbon atoms.
3. The water-glycol hydraulic fluid according to claim 1 , wherein the fatty acid is lauric acid having 12 carbon atoms.