There are hydraulic slow closing butterfly valves, hydraulic ball valves, electric plunger valves installed before the water turbine in hydro power plants. There are large size vacuum butterfly valves, hydraulic butterfly type check valves, electric butterfly valves, pneumatic emergency shut down butterfly valves & check valves, high temperature high pressure gate valves, globe valves, check valves in cast materials of WC6, WC9, C5, C12, C12A and forged materials of A105, F11, F22, F91, abrasion resistant ceramic ball valves, ceramic double wedge gate valves, wear resistant ceramic lined pipes, elbows and tees etc. used in thermal power plants. Abrasion resistant ceramic ball valves and metal to metal seated ball valves are also used in waste to energy power plants. Hydraulic butterfly type check valves and electric butterfly valves are also used in nuclear power plants.