GB 9440-88 is a national standard issued by the Ministry of Industry and Information Technology of the Peoples Republic of China. It specifies technical requirements, test methods and inspection rules, conditions of supply and acceptance, and packaging, marking and quality certificate of cast iron castings and forgings.
GB 9440-88 applies to cast iron castings and forgings of various shapes and sizes. It is suitable for cast iron materials used in the manufacture of tools, machinery and other mechanical parts as well as structural parts. Its technical materials mainly include grey cast iron, nodular cast iron and malleable cast iron. This standard also defines the two types of base casting and forging products.
The mechanical properties of cast iron castings and forgings in accordance with GB 9440-88 should mainly meet the requirements of the following four aspects: first, comprehensive mechanical properties: tensile strength, elongation, hardness and impact toughness; second, hardness in the range of HB170-220, surface hardness should be appropriate; third, nozzle tightness test, no through holes; fourth, the casting surface should be smooth without obvious bottom or irregular marks.
To meet the requirements of GB 9440-88, the supplier should purchase qualified raw materials, conduct heat treatment in accordance with the applicable standards, and perform quality inspections at each related production process to ensure product quality. In addition, the packaging of cast iron castings and forgings should meet the requirements of the standards, and the quality certificate should be issued when the products are shipped.
Adhering to the quality policy of Product Quality is Life, enterprises that manufacture and supply cast iron castings and forgings in accordance with GB 9440-88 must pay close attention to the quality of the products throughout the production process. Through continuous improvement of technology and implementation of scientific management, manufacturers can effectively guarantee the performance and quality of the products, win customers’ trust, and improve the business relationship between manufacturers and customers.
