Valves with metal seats are designed for abrasive type services or operations with temperatures that prohibit the use of an elastic material. The function of the seat is given by the contact between the metal of the ball and the seat, which is hard metal.
The main characteristic of metal-seated valves is their ability to withstand higher temperatures and more intense operating conditions than soft-seated valves. The metal seat can withstand temperatures up to 550°C, resists cavitation due to the passage of abrasive agents and hydraulic shocks the most, so valves with metal seats are best suited for systems with high corrosion or erosion rates.
Metal seats can be hardened by ultrasonic coating, tungsten carbide, chromium carbide.