Seals refer to components that prevent fluid or solid particles from leaking between adjacent bonding surfaces and prevent external impurities from entering the interior of machinery and equipment. Seals are essential basic components in industrial manufacturing processes, with applications in fields such as automobiles, home appliances, engineering machinery, aerospace, and petrochemicals. With the sustained growth of China's economy and the continuous expansion of industrial scale, the demand for seals in downstream markets continues to rise.

The sealing industry in China has made significant progress through continuous development, and the products produced can basically meet domestic demand, becoming an important basic industry for the development of China's machinery industry. According to the "2019-2023 China Seal Industry Market Supply and Demand Research and Consulting Report" released by the New Frontier Industry Research Center, the market share of metal seals in China's seal industry is 71%, rubber seals is 18%, and plastic and other seals is 11%. Metal seals dominate the sealing market in China, while rubber seals also have a significant market demand.

Metal seals are important basic components of mechanical equipment, widely used in industries such as machinery, petroleum, chemical, metallurgy, and power. Their market demand is greatly influenced by downstream industries. Since 2010, the sales revenue of China's metal seal industry has shown a fluctuating development trend. In 2017, the sales revenue of China's metal seal industry was 73.91 billion yuan, a year-on-year decrease of 10.7%; The total industry profit was 6.09 billion yuan, a year-on-year decrease of 4.1%. In 2017, the decline in sales revenue and profits of China's metal seal industry was not only affected by downstream industries, but also by the rise in the price of raw materials such as steel required for production.

In 2017, the market size of rubber seals in China was 16.8 billion yuan, a year-on-year increase of 12.1%. Compared to metal seals, the development trend of China's rubber seal industry is relatively good, with an overall upward trend except for a slight decline in sales revenue in 2014-2015. There is still a significant gap in the quality and variety of rubber seal products in China compared to developed countries, which cannot meet the market's standardization and serialization needs. With the rapid development of China's automotive industry, there is a huge demand for high-performance rubber seals in the market, especially in the field of rubber seals for key parts of high-end cars. Domestic enterprises are unable to meet the demand, and the market still relies on imports.

With the continuous growth of market demand, the scale of China's sealing industry is constantly expanding. At present, there are numerous enterprises in China's sealing industry, mainly distributed in Shandong and the Yangtze River Delta region. But overall, except for a few strong enterprises with good competitiveness, most enterprises are small in scale, slow in technological progress, and have weak competitiveness. Therefore, China's sealing industry is at a disadvantage in international market competition, and the industry structure urgently needs to be adjusted and upgraded.