Dalian castings have a long history of application. In ancient times, people used castings and some household appliances. In modern times, castings are mainly used as blanks for mechanical parts, and some precision castings can also be directly used as mechanical parts. Castings account for a large proportion in mechanical products. For example, in tractors, the weight of castings accounts for approximately 50-70% of the total weight, 40-70% in agricultural machinery, and 70-90% in machine tools and internal combustion engines.
The quality of castings has a significant impact on the performance of mechanical products. For example, the wear resistance and dimensional stability of machine tool castings directly affect the precise maintenance life of the machine tool; The size, surface accuracy, and roughness of each pump impeller, pump casing, and hydraulic component directly affect the efficiency, energy consumption, and cavitation development of the pump and hydraulic system. The strength and heat resistance of castings such as internal combustion cylinder blocks, cylinder heads, cylinder liners, piston rings, and exhaust pipes directly affect the working life of the engine.
Expressions of Dalian Casting Parts
Carbon and iron filings are two forms of surface defects in cast iron castings. During the casting process, the solid liquid products of vaporization and cracking aggregate into orange peel like carbon defects on the surface of the casting, while the low filling temperature of liquid metal leads to wrinkling of the casting surface. 100mm for severe parts × The surface wrinkling area of 60mm castings is divided into 5 levels. First class: very slight wrinkling (against fire); Level 2: Mild wrinkling; Level 3: Moderate wrinkling; Level 4: Severe wrinkling; Level 5: Severe wrinkling.
According to the quality inspection results of precision casting, it is generally divided into three categories: qualified products, repair products, and scrapped products. Qualified products refer to castings with appearance quality and basic quality that meet relevant technical requirements or delivery engineering acceptance technical requirements; Repaired products refer to castings whose appearance and basic quality cannot fully meet the requirements and engineering acceptance conditions, but are allowed to be repaired. The castings specified in the specifications and technical conditions shall be accepted as qualified castings; Defective products refer to castings that do not meet the appearance and basic quality standards, have not been repaired, or do not meet the acceptance standards and technical requirements of precision casting.
Data shows that in recent years, the aluminum zinc alloy die-casting industry in China has developed rapidly, with production increasing year by year. On the one hand, driven by the trend of lightweight automobiles, there is a huge demand in the global aluminum alloy die-casting market. In recent years, the internal optimization and upgrading of the automotive industry have stimulated the demand for aluminum alloy die-casting. On the other hand, due to the development of the global die casting industry, the demand for aluminum alloy die castings in various industries is also constantly increasing. The focus of global zinc alloy die-casting production is gradually shifting to China, coupled with China's unique labor and aluminum resource advantages, undoubtedly leading to the rapid development of the die-casting industry.
