Seals refer to parts that prevent fluid or solid particles from leaking from adjacent joints and external impurities from intruding into machinery and equipment. Seals are indispensable basic components in the process of industrial manufacturing. They are widely used in automotive, household appliances, construction machinery, aerospace, petrochemical and other fields. With the sustained growth of China's economy and the continuous expansion of industrial scale, the demand for seals in the downstream market continues to rise.

With the continuous development of Seals Industry in China, great progress has been made at this stage. The products produced can basically meet the domestic demand and become an important basic industry for the development of China's machinery industry. According to the Consultation Report on Supply and Demand of Seals Industry in China from 2019 to 2023 issued by New Sijie Industry Research Center, the market share of metal seals, rubber seals and plastic and other seals is 71%, 18% and 11% respectively. 。 Metal seals play a dominant role in the seals Market in China, and rubber seals also have a larger market demand.

Metal seals are important basic parts of mechanical equipment, which are widely used in machinery, petroleum, chemical industry, metallurgy, power and other industries. Their market demand is greatly affected by the downstream industry. Since 2010, sales revenue of metal seals industry in China has shown a fluctuating development. In 2017, the sales revenue of China's metal seals industry was 73.91 billion yuan, down 10.7% from the same period last year; the total profit of the industry was 6.09 billion yuan, down 4.1% from the same period last year. In 2017, besides the downstream industry, the decline of sales revenue and profit of metal seals industry in China is also affected by the rising price of raw materials and steel for its production.

In 2017, the market size of rubber seals in China was 16.8 billion yuan, an increase of 12.1% over the same period last year. Compared with metal seals, rubber seals industry in China has a better development trend. Except for the decline in sales revenue from 2014 to 2015, the overall trend is upward. Compared with developed countries, the quality and varieties of rubber seals in China still lag far behind, which can not meet the standardization and serialization needs of the market. With the rapid development of China's automobile industry, there is a huge demand for high-performance rubber seals in the market. Especially in the field of rubber seals in key parts of high-grade cars, domestic enterprises can not meet the demand, and the market still needs to rely on imports.

With the increasing market demand, the scale of China's seals industry is expanding. At this stage, there are many enterprises in China's seals industry, mainly distributed in Shandong and the Yangtze River Delta region. But on the whole, except for a few strong enterprises with better competitiveness, most of them are small in scale, slow in technological progress and weak in competitiveness. Therefore, China's seals industry is at a disadvantage in the international market competition, and the industry structure needs to be adjusted and upgraded urgently.