Diaphragm valve DIASTAR PVDF Ten FO

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The Georg Fischer SYGEF Standard DIASTAR Ten pneumatic diaphragm valve with Fail Safe to Open (FO) function is engineered for reliable isolation and throttling in chemical distribution, pharmaceutical purified water, and ultrapure utility piping systems. Actuated pneumatically by spring force in the absence of control air pressure, the FO configuration guarantees immediate full-bore passage whenever pilot pressure drops, securing processes that demand fail-safe open fluid continuity. The valve features a rugged PVDF housing paired with an optimized internal flow geometry that delivers up to double the flow rate compared to earlier designs, minimizing turbulence and pressure drops across nominal sizes d20 to d63 mm (DN15 to DN50). Its housing nut construction replaces traditional four-bolt patterns with a single uniform tensioning point, ensuring consistent radial compression over the diaphragm and significantly reducing maintenance duration. Designed with union ends featuring metric butt fusion spigots, the unit allows swift radial installation and dismounting without straining adjacent pipe runs, while offering seamless compatibility with infrared (IR Plus) and bead and crevice-free (BCF Plus) fusion welding technologies. The high-purity PVDF wetted body combined with inert PTFE/EPDM or PTFE/FKM diaphragms and FKM seals resists aggressive media including oxidizing acids, halogens, and deionized water across an operating temperature range from -20 degrees Celsius to +140 degrees Celsius at nominal operating pressures up to 10 bar. Actuator air connections rotate at 90-degree intervals to accommodate constrained industrial skids and automate dosing loops with absolute process integrity.