| abstract |
As a flame retardant hydraulic oil composition which is most suitable for use at a place where the risk of fire breakout is high under high-temperature and high-pressure conditions, can be applied to a high-pressure pump, has high wear resistance, seize resistance, and sludge inhibiting performance, and can be used for a long period of time, a flame retardant hydraulic oil composition containing (A) at least one base oil selected from hydrocarbon oils, synthetic esters, oils and fats; (B) a carbodiimide compound represented by formula (1) and/or an epoxy compound in an amount of 0.01 to 2% bymass based on the total amount of the composition; and (C) at least one anti-wear agent selected from sulfur-containing phosphoric acid esters, acidic phosphoric acid esters, acidic phosphoric acid ester amine salts, and phosphorous acid esters in an amount of 0.001 to 5% by mass based on the total amount of the composition is provided. |