Seals are materials or parts that prevent fluid or solid particles from leaking from between adjacent bonding surfaces and prevent foreign impurities such as dust and moisture from entering the components inside the machine. The storage temperature of the seal is preferably below 30 ° C to avoid high temperature aging of the seal. Seal development Although the rubber seal is small, its role makes it a basic component and accessory in the main national economic industries such as national defense, chemical industry, petroleum, coal, transportation and machinery manufacturing, and it plays a very important role in the development of the national economy. In recent years, with the rapid economic growth, the rubber and plastic seal manufacturing industry has maintained double-digit growth. The data shows that in 2011, the size of China's rubber and plastic seal manufacturing industry (above companies (according to the statistical caliber of the National Bureau of Statistics, sales revenue of more than 20 million yuan) achieved a total industrial output value of nearly 10 billion, an increase of more than 20%. China Rubber and Plastic Seals There are more than 150 companies in the manufacturing industry (with an annual income of 20 million yuan), and the domestic rubber seal industry generally shows a small-scale and low-tech development situation. From the perspective of the economic type of enterprises, private and foreign-funded enterprises account for The ratio is over 95%, which is the main economic type of the industry. At the same time, enterprises are basically concentrated in East China. From the number of enterprises, sales revenue and asset scale, East China has occupied a considerable share and the market concentration is high. A private enterprise in China's seal industry serves a variety of customers with high-quality products and efficient service concepts.