What is the reason why the double-cylinder pneumatic butterfly valve can't be closed after opening?

The following are some well-known brands recognized by the valve industry, which are widely recognized and enjoy a high reputation. Although the ranking may change with time and market conditions, the following brands are generally considered as one of the top brands in the valve industry:

The following influential first-line brands of water system valves and industrial valves can be used for reference only: Suzhou Newway Valve, Shanghai Guanlong Valve, Shanghai Zhong Qi Valve, Sanhua, Su Yan, Shentong, Sufa, Nanfang, Jiang Yi and Yaozi.

The above manufacturers are only for estimation and reference, and the specific situation may be different or floating at any time due to a series of factors such as changes in market conditions, the size of competition pattern and the stability of product quality. Valves are indispensable key equipment in industrial production and civil facilities, and their brand quality and reputation directly affect users' satisfaction and trust.

These brands are famous for their innovative technology, high-quality products and reliability in the valve industry. It is worth noting that the market and industry are developing rapidly, and different rankings may be different due to time and region. For the latest ranking information, it is recommended to refer to industry reports, professional institutions or market research data to obtain more detailed and accurate information.