The hydraulic oil in this dataset consists of trimethylolpropane oleate (base oil), thiadiazole polysulfide (used as extreme pressure agent, auxiliary antioxidant, and rust inhibitor), and phosphate ester (anti-wear additive). It belongs to the synthetic ester-type fire-resistant hydraulic oil, featuring excellent high-temperature thermal stability and shear stability, long service life, high viscosity index, good biodegradability, and very low aquatic toxicity. This hydraulic oil product is suitable for various hydraulic systems operating under severe conditions, such as ladle turret and finishing hydraulic systems in continuous casting production lines at steel plants, reel machine hydraulic systems in hot rolling mills, high-temperature operations such as metal melting, and fire-resistant hydraulic systems required in blast furnaces, furnace dismantling machines, hot rolling mills, foundries, ladle valve systems, power stations, and coal mines.