The Asahi America Type 57 wafer-style butterfly valve with a lever handle is made of polyvinyl chloride (PVC) and has ethylene propylene diene monomer (EPDM) seats and seals, a polypropylene (PP) disc, and flanged connections. Made of PVC for corrosion resistance and less weight than valves made from metals, this wafer-style valve fits between two pipe flanges and is designed to retain a seal against two-way pressure to prevent backflow in single-direction systems. The EPDM rubber seats and seals provide increased water and chemical resistance, and a plastic lever handle provides manual flow control. The disc is made of polypropylene for resistance to various chemicals and less weight than similar discs made from metal. The maximum pressure is 150 pounds per square inch (psi) for use with water, oil, and gas (WOG), and the working temperature range is 30 to 120 degrees F. This valve has flanged connections for bolting to pipes for greater ease in installation and maintenance than welded connections, and a molded International Organization for Standardization (ISO) bolt circle on the top flange for accessory mounting. It meets National Sanitation Foundation (NSF) 61 quality assurance requirements for use in drinking-water system components. This butterfly valve is for use in applications including chemical processing, water and wastewater systems, Irrigation, food processing, and mining.
Butterfly valves are used to regulate flow between pipes, tubes, and hoses by rotating a lens-shaped disc in the center of the valve and are suited for high-capacity, low-pressure applications. When the valve is fully opened, the disc face is parallel to the inlet and outlet of the valve, and when the valve is closed, the disc face is perpendicular to the opening of the valve. Butterfly valves may have a handle or lever that aligns with the disc position (open or closed) for manual flow control. They are primarily used in applications including agriculture, water treatment, fire protection, compressed air or gas, and vacuum service.
Asahi/America, Inc. manufactures corrosion-resistant fluid flow products, including thermoplastic valves, actuators, flow meters, tubing systems, and single and double containment piping systems. The company, founded in 1977, and headquartered in Malden, MA, meets International Organization for Standardization (ISO) 9001:2008 and National Sanitation Foundation (NSF) 61 standards.