By adjusting the components of the cleaning agent,the wettability and spreadability of the workpiece surface were increased,and a uniform water film was formed on the workpiece surface while the oil was removed.With the anti-rust treatment,a uniform anti-rust film was formed on the surface of the workpiece,which effectively reduced the residue on the surface of the workpiece after nitriding treatment.After on-site testing and verification,the residue of the workpiece after nitriding was significantly reduced,and it was expected to be widely used in the nitriding process in the precision hydraulic industry.