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Casting technology is one of the main methods to obtain mechanical products blank, is an important basic process of casting machinery industry, occupies an important position in the national economy.

Currently, the development of precision casting technology in industrial developed countries in the world can be roughly summarized into four goals, namely:

1. Improve casting quality and reliability, and produce high-quality near-final casting;

2. Shorten delivery time;

3. Protect the environment and reduce or even eliminate pollution;

4. Reduce production costs. The current status of precision casting technology in China is large output, with an annual output of about 12 million tons of castings, more than 20,000 factories and more than 1.2 million employees of casting technology. One of the characteristics of China's foundry technology industry is the rapid development of township enterprises since the reform and opening up to become an important force in China's foundry technology industry. The number of township precision foundries has exceeded the number of state-owned foundries, and the casting output of township foundries accounts for about half of the total casting output in China.