The increasing demand of severe-service applications with extreme operating conditions has pushed the limits of commonly used valve materials. Metallurgists and materials engineers such as Velan's Dr. Fadila Khelfaoui are therefore developing novel material solutions and processes to sustain the extreme operating conditions of the valves. Valve components, such as wedge, disc, ball, and seat, are hardfaced to reduce the effects of friction, wear and corrosion and thus enhance their in-service life. Cobalt-based alloys are commonly used due to their unique galling performance, low coefficient of friction, and superior corrosion resistance at temperatures up to 650°C (1,200°F). These features help to prevent the valve components from seizing, suffering surface deterioration, and/or being affected by gross material transfer between two counter bodies.
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