With the rapid development of China’s automobile manufacturing industry, many high-end automobile brands have been launched almost at the same time with developed countries, and the corresponding automobile delivery machine manufacturing industry has also been developed rapidly, among which the level of engine casting has also been greatly improved. No matter the casting output, casting technical requirements and casting quality, they have basically met the requirements of modern automobile development The increasing demand for motivation.
Taking the production of cylinder block (cylinder head) of main castings for small and medium-sized passenger engine as an example, many automobile engine foundry enterprises have adopted clay sand high-pressure molding (a few of them are self hardening resin sand molding), while core-making generally adopts coated sand hot core or cold core technology, while in the smelting area, most of them adopt duplex smelting or electric furnace smelting, and the engines produced are high-strength thin-wall iron parts 。 In order to meet the technological requirements of high-strength thin-walled iron castings, many manufacturers have introduced advanced technological equipment, such as high-efficiency sand mixer, high-pressure molding line, highly automatic core making center, and powerful shot blasting equipment, most of which are integrated dip coating, drying and automatic core removal. In the aspect of process quality control, many enterprises have realized online detection and control, such as equipped with online detection of molding sand performance, hot metal quality detection and judgment device by thermal analysis, and rapid detection by vacuum direct reading spectroscopy. Industrial endoscope for cleanliness inspection, etc. A considerable number of enterprises have also applied computer model simulation technology in product development. It is no exaggeration to say that in terms of hardware parts, China’s engine casting level is no less than that of the developed countries in the world. In a word, it has modern casting production conditions.
However, it should be acknowledged that there is still a big gap between us and the developed countries in terms of economic benefits, product quality and technical requirements of engine casting enterprises.
To improve the quality of production and reduce the loss of waste products is an important way to narrow the gap with developed countries, give full play to the efficiency of imported equipment and improve the efficiency of enterprises. This paper attempts to discuss the common casting defects and Countermeasures in the production of gray cast iron cylinder block (cylinder head) castings of small and medium passenger car engines in China’s foundry enterprises under modern casting conditions.