Pneumatic Diaphragm Valve PP-H DIASTAR 025 FO d75-160mm

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The Georg Fischer PROGEF Standard Diaphragm Valve DIASTAR Series 025 FO is a pneumatically actuated industrial valve engineered for corrosive chemical processing, water treatment systems, and demanding fluid automation. Manufactured from unpigmented beta polypropylene homopolymer (ß-PP-H) in compliance with EN ISO 16138, this valve provides exceptional chemical resistance against acids, alkalis, and aggressive process media across industrial piping networks. Supplied across Europe by BigWeld, an authorised Georg Fischer distributor, this diaphragm valve delivers long-term process reliability and precise flow throttling.

The pneumatic actuator operates on a fail-safe-to-open (FO) principle, automatically driving the valve to the fully open position upon loss of compressed air signal to maintain continuous system discharge or pressure relief. Enclosed in a rugged, glass-fibre reinforced polypropylene (PP-GF) housing, the actuator mechanism resists harsh atmospheric exposure and airborne chemical vapors. It features pre-stressed corrosion-resistant springs, an integrated optical position indicator for clear visual status verification, and robust stainless steel assembly bolts that maintain uniform clamping pressure on the diaphragm interface.

Engineered with fixed metric backing flanges for direct bolting into metric piping spools, the valve accommodates pipe outside diameters of 75 mm, 90 mm, 110 mm, and 160 mm. The weir-style body geometry facilitates linear throttling characteristics and low pressure loss while eliminating dead legs where process media could crystallize or stagnate. Internal fluid containment is secured through high-grade diaphragm options in either flexible EPDM elastomer or chemical-grade PTFE/EPDM composite, ensuring zero leakage across the seat and complete isolation of the operating mechanism from the transported media.

Designed for operating temperatures ranging from 0 degrees up to 90 degrees Celsius, this PP-H pneumatic valve integrates seamlessly into automated chemical distribution skids, industrial wastewater treatment facilities, and process cooling loops requiring automated fail-safe operation.