Analysis Of Lined Ball Valve Application Status

Lined Ball Valve are essential equipment for the safe operation, maintenance, renovation, and development of gas transmission, distribution, and storage systems. Improperly selected or poorly made ball valves can cause leaks, production stoppages, and other accidents. These accidents can disrupt normal life and production, or even cause significant damage to the nation, people, and property. Therefore, careful selection of gas ball valves is crucial.

With the development of the gas industry, demand for specialized gas ball valves is increasing. Our factory continuously releases new products to meet market competition. Currently, buried gas ball valves in my country are primarily categorized by structure into floating and fixed ball valves. Drive modes include manual, worm gear, electric, pneumatic, and gas-hydraulic transmission. Installation methods include gate wells and direct burial. According to relevant data, the most widely used manual, fully welded ball valve in urban coal-to-gas transmission and distribution systems is the Hebei, Hongqiao, and Beichen districts of Tianjin. The city's three districts, Hebei, Hongqiao, and Beichen, have over 120 kilometers of medium-pressure pipelines and over 300 valves, over 80% of which are ball valves, followed by butterfly and gate valves. Before the gas source conversion project, the gas pipelines in the three districts mentioned above operated with manufactured coal gas. Manufactured coal gas contains numerous impurities, particularly a mixture of tar, aromatic hydrocarbons, and dust, forming a "gas glue" that often compromises valve sealing and can even cause valve stem seizure. Therefore, we primarily selected valves whose structural features address this issue, ensuring flexible opening and closing and leak-free operation. After years of practical experience and data analysis, we found that ball valves (both floating and fixed) are most suitable. However, with the completion of the Tiandai Coal Project, the properties of natural gas have changed. While natural gas is cleaner and drier than coal-fired gas, it contains sandy dust and operates at higher pressures. Under high pressure, sand and dust can significantly scour the valve cavity. Furthermore, natural gas contains highly corrosive hydrogen sulfide. Therefore, the selection of natural gas ball valves for urban underground pipelines presented a new challenge.