The wear resistance and dimensional stability of copper castings in the process of production directly affect the accuracy and service life of their machine tools to a certain extent. The size, accuracy and surface roughness of the impeller, shell and inner cavity of hydraulic parts of various pumps directly affect the working efficiency, energy consumption and cavitation development of pumps and hydraulic systems; The strength and resistance to chilling and heat shock of internal combustion engine cylinder block, cylinder head, cylinder liner, piston ring, exhaust pipe and other castings directly affect the service life of the engine.
Copper castings are widely used in industry, especially in construction machinery. Copper castings should have reasonable casting process. That is, according to the structure, weight and size of the casting, the characteristics of the casting alloy and the production conditions, select the appropriate parting surface, modeling and core making methods, and reasonably set up the casting reinforcement, chill, riser and gating system. To ensure high quality castings. Without the improvement of the quality of machine tool castings, the development of machine tool equipment manufacturing and the improvement of the overall level are impossible to talk about, which will affect the competitiveness of China's machine tool equipment manufacturing industry in the international market and continuously improve the quality of machine tool castings, so as to ensure the overall improvement of machine tool manufacturing level.
The process flow for general copper castings is as follows: alkaline chemical degreasing → hot water washing → clean water washing → soaking in 25% hydrofluoric acid → clean water washing → mixed acid corrosion → clean water washing → soaking in 5% alkaline solution → clean water washing → pre copper plating → clean water washing → silver plating → clean water washing → passivation → clean water washing → film removal → clean water washing → soaking → clean water washing → hot water washing → drying → inspection.
Many parts and components of copper castings are made of copper in the process of manufacturing, so their precision should be higher, and the quality is appropriate and good in use. As long as they are normally used in operation, they can be used for a long time without any problems. However, this kind of casting is not completely uncured, which can ensure a relatively long service life. It is still necessary to do a good job in basic maintenance.
If there are pollutants on the surface of copper castings during processing, the cleaning operation must be completed in time, and the chemical protection can be done as much as possible. Although it cannot be directly applied to thick grease, some special maintenance oil can be used, which can effectively play a maintenance role. During daily wiping, do not use water directly, but use soft cloth to avoid the attack of scratches.
