Special steel parts are uneven, and the treatment method needs to be comprehensively considered according to the specific reasons and the material, shape, purpose and other factors of the parts. The following are some common treatment methods and suggestions: 1. Cause analysis ① Improper material treatment: Special steel parts such as steel surface have oil stains, rust or iron filings and other impurities, or in the pre-treatment process pickling, oil removal and other processes are not handled properly, which may affect the flatness of the steel surface. ② Processing process problems: Special steel parts in the processing process, such as cutting, stamping, welding and other process parameters are not set properly, which may lead to uneven surface of the parts. ③ Environmental factors: such as temperature control during heat treatment, cooling rate, etc., as well as environmental factors during storage and transportation, may have an impact on the surface flatness of parts. Second, treatment methods ① Dressing and processing Mechanical dressing: Use tools such as grinding wheels, files, and grinders to trim the uneven surface to achieve the required flatness. This method is suitable for parts that are partially uneven and easy to machine. Cold pressing method: For materials such as stainless steel, cold pressing method can be used to press the surface of the dent inward to restore the flatness. This method is simple and effective, but attention should be paid to maintain uniform pressure to avoid new damage to the parts. ② Heat treatment High temperature tempering: For the unevenness caused by improper heat treatment, the internal stress can be eliminated and the surface flatness can be improved by high temperature tempering treatment. However, attention should be paid to controlling the tempering temperature and time to avoid adverse effects on the performance of the parts. Local heating repair: For stainless steel and other materials, the high temperature method can be used to heat the dent to a certain temperature to soften the metal material and restore the shape. Then use professional tools for leveling treatment. This method repairs the dent effect better, but attention should be paid to the heating temperature and time control. ③ Surface treatment Sandblasting treatment: The high-speed moving sand grains are sprayed to the surface of the part through the sandblasting machine to remove the unevenness and achieve a certain roughness requirement. This method is suitable for large area uneven parts treatment. Chemical treatment: Chemical treatment methods such as pickling and passivation can remove impurities such as rust and oil on the surface of parts, and improve the surface finish. However, attention should be paid to control the treatment time and concentration to avoid corrosion to parts. ④ Replacement or scrapping If the uneven condition of parts is serious and cannot be repaired to a state that meets the requirements of use by the above methods, or the repair cost is too high, it is recommended to consider replacing new parts or scrapping treatment. III. Preventive measures ① Strengthen material management: Ensure that the surface of steel is clean and free of impurities, and strictly control the quality of pickling, oil removal and other processes during the pretreatment process. ② Optimize processing technology: Reasonably set processing parameters, such as cutting speed, stamping pressure, welding temperature, etc., to reduce the uneven phenomenon generated during processing. ③ Improve storage and transportation conditions: Avoid external forces such as extrusion and collision for special steel parts during storage and transportation to maintain their surface flatness.