Ball valves are commonly used as fluid shutoff valves in onshore and offshore oil and gas production facilities. They are also used in fuel gas system feeding furnaces. Ball valves are designed to control the flow of high-pressure gasses and liquids with minimal pressure drop. They have a very low response time which means they are quick to open and close, and these valves have a tight-sealing capability with low torque. Ball valves can be used in various remote locations within petrochemical industries as these valves are versatile and easy to operate and repair.
Ball valves are available in numerous styles like a reduced bore, full bore, v-port, floating-type, and true-union, making these valves highly versatile. A floating ball valve works better in a low to medium pressure pipeline, whereas a trunnion ball valve can be used in high-pressure conditions.
Ball valves are suitable for pigging. Pigging is the process of cleaning a gas pipeline where a device known as a pig travels through the pipeline. This process is not supported by certain valve types that do not allow the free travel of pig through the connected valve. For example, a butterfly valve has a rod running through its center that obstructs the path of a running pig rendering the valve incapable of pigging applications. A full bore ball valve lends itself to the pigging application. In an open state, the bore of the valve is parallel to the inlet and outlet ports; hence, there is no visual difference between the valve and pipe bores. In this way, a pig can have an unrestricted flow through a full bore ball valve unrestricted, thereby cleaning the bore of the valve along with the entire pipeline.
Ball valves are used primarily for low-pressure applications, where rubber seals can be used. For high pressure and high-temperature applications, choose a ball valve with a metal seat. Ball valves handling combustible and dangerous fluid media are provided with an emergency seat seal. These emergency seat seals are made of metal and are attached adjacent to the ball so that the ball can move against the metal seal in case the original soft seal catches fire. For maximum life and performance of the valve, choose materials like brass, aluminum, steel, or cast iron for the body. The packing material must be capable of lasting through a fire.
