Metal Seated vs Soft Seated Ball Valve
Soft seats provide low-friction sealing when the selected polymer is compatible with the pressure, temperature and process fluid. Metal-to-metal seats are considered when heat, abrasion, erosion, solids or severe cycling move the service outside practical soft-seat limits.
Metal seating normally introduces coating or hardfacing, lapping, tighter surface control and higher operating torque, while soft seating requires careful review of polymer temperature, creep, decompression and chemical compatibility.
The buyer should state maximum and normal temperature, solids content, shutoff requirement, cycling frequency and fluid composition before deciding whether a metal-seated or soft-seated ball valve is appropriate.