Series A31 & A32 Abrasion resistant centric butterfly valves feature a lock type seat, spherical sealing surface disc and strong stem-to-disc connection for easy use in many industrial applications especially Mining Industry, dry bulk conveying, paper mills, and all users of Slurry and High Abrasion applications. With the field replaceable seat fully isolating the body and shaft from the media, and the heavy duty construction for severe vacuum up to 285 psi, the valves are also widely used in food and beverage processing, vacuum desulphurization plants, shipbuilding, HVAC, etc.