Stainless Steel Butterfly Valve. Valve Body Materials: carbon steel, stainless steel and alloy steel. Valve Connection: wafer, lug, flanged and BW. Manufacturing Standard: BS 5155. Butterfly Valve Sealing: metal-seated and resilience-seated. Valve Size range: from 1-1/4 to 120 inches (DN32 to 3,000mm). Pressure: from PN0.1 to PN6.4MPa. Applicable temperature: from -196 to +650°C.