The invention provides a high-temperature detergency
zinc-free hydrogenated hydraulic oil composition, and relates to the technical field of hydraulic oil additives. The hydraulic oil composition is prepared from the following components in percentage by weight: 0.2 percent to 0.4 percent of an anti-wear agent, 0.05 percent to 0.1 percent of an extreme pressure agent, 0.02 percent to 0.05 percent of a
metal deactivator, 0.1 percent to 0.3 percent of an
antioxidant, 0.05 percent to 0.1 percent of an anti-
rust agent, 0.01 percent to 0.03 percent of a cosolvent, 0.01 percent to 0.04 percent of a
clearing agent, 0.2 percent to 1.0 percent of a
pour point depressant, 0.01 percent to 0.05 percent of a de-
foaming agent, 0.01 percent to 0.05 percent of a de-emulsifier and 98 percent to 99 percent of II type or III type
base oil. The hydraulic oil disclosed by the invention has excellent
wear resistance, water separation property, filterability, anti-
rust property, hydrolytic stability,
oxidation resistance,
thermal stability and high-temperature detergency.