Velan, Inc. Triple-offset Valves

Bidirectional, zero-leakage, triple-offset butterfly valves Features and benefits The Torqseal's advanced design features three-way eccentricity and unique elliptical seat geometry ensuring compressive sealing around the entire seat and a "tightâ€, bubble-free valve. • CoCr alloy hardfaced seat: Raised, conical seat prevents solids build-up from interfering with the seal. Seat is hardfaced with CoCr alloy to meet severe service (in lieu of soft 316 SS hardfacing). • STANDARD LAMINATED RESILIENT DISC SEAL TO 800°F (427°C): One to four graphite layers are carefully assembled between stainless steel rings and graphite using phenolic resin bond. Solid seal rings are available for abrasive services as well as high temperature applications up to 1112°F (600°C). • ""ZERO LEAKAGE" SEAT TIGHTNESS (API 598 RESILIENT SEAT STANDARD): The disc seal, evenly compressed around its circumference, produces a wedging effect which flexes the seal ring and reacts like a spring. The resilient seal assures "zero leakage" of liquids or gases to API 598 resilient seat standard. Resiliency in the seal allows disc movement during thermal cycles while retaining tight shutoff. • NO CAVITY: There is no cavity to allow build-up of solids. • ONE-PIECE SHAFT: Large diameter shaft for safety is connected to the disc close to the bearings to absorb loads with taper pin and key to allow for differential expansion due to temperature. • SHAFT BEARINGS: The shaft is centered on two long bearings, chromed, nitrided, or as stellite (option) protected against the entrance of solids by bearing seals which are standard on Torqseal valves. • LOW EMISSION SHAFT SEALS 0 - 100 PPM: Shaft is burnished to 8 RMS, ID of packing chamber finish 32 RMS. Live-loading available for long maintenance-free service. Easy access for packing adjustment. • CERTIFIED TO API 591, PED & ASME N (UPON REQUEST)