This is a fire-safe ball valve that is manufactured through the forging method. This makes the ball bore rotate and become perpendicular to the pipeline and thus block fluid flow.įigure: Working of a fire safe ball valve. ![]() ![]() To close the fire safe ball valve, the handle is turned for another 90 o opposite to the direction turned when opening the valve. When the ball is rotated for 90 o it becomes in line with the pipeline and thus allows fluid to flow. This makes the handle which is connected to the ball via a valve stem to rotate the ball. To open a fire-safe ball valve, the handle is rotated for 90 o. The working of a fire safe ball valve to allow fluid flow depends on a ball with a bore at its center. The normal operation of a fire safe ball valve that is opening and closing fluid flow is also maintained. In the stem packing, the thermoplastic seal material is supported by the use of graphite seal as the secondary packing in case of fire. In the seat design, the thermoplastic melts in case of high temperature and the valve seal is obtained by use of a body machined to serve as a secondary seal. The other method uses a thermoplastic stem packing and thermoplastic seat material like PTFE. In a fire-safe ball valve with a stem packing and seat insert, the graphite remains even when the valve is exposed to fire. The method of using a fire-proof component uses a metallic seat, graphite seat insert, and graphite packing on the stem. One method is by using a fire-proof component and the other method is by using non-fire proof component supported by a special design that prevents leakage after the material melts. The two methods are used to achieve a fire-safe ball valve design. The leakage could occur from the stem and or the seat. Two types of fluid leakages are avoided by using a fire safe ball valve that is before the fire and after the fire. Fire-safe ball valve manufacturers are tasked to ensure a tight shut-off of the valve during and after fire outbreaks. Fire safe ball valves are mostly used in refining and chemical processing plants to help in handling flammable fluids. As such, a fire safe ball valve is needed so that it will not leak fluid when it gets exposed to fire. The fluid leakage will support the fire and make it grow bigger than before. If a ball valve that is not fire safe is used and fire occurs, it will cause fluid leakage from the valve stem. A fire safe ball valve is used because of possible flammable or hazardous fluid leakage from the valve in case of a fire outbreak. A fire-safe ball valve should be able to maintain its ability to contain pressure during and after a certain duration of fire exposure. The actuator that can be used for fire-safe ball valves is electric or pneumatic. Fire-safe ball valves are operated manually using a hand lever or using an actuator. These standards are followed by the fire safe ball valve manufacturers to ensure the valve can work as required. ![]() There are certain design and test standards considered in fire-safe ball valves. Because most of the valves are made up of non-alloy materials for sealing, they have to maintain functionality even at high temperatures or fail in a predictable way that differentiates fire-safe ball valves and other types of ball valves. Fire-safe ball valves are valves designed to reduce downstream leakages and fugitive emissions in case they are exposed to high-temperature fires.
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