DIASTAR Diaphragm Valve 025 FC PP-H d75-160

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The Georg Fischer PROGEF Standard DIASTAR 025 FC flanged diaphragm valve is an engineered flow regulation and shut-off solution designed for demanding chemical processing, industrial effluent treatment, and high-purity water applications. Operating on a pneumatic fail-safe-to-close (FC) mechanism, this valve provides dependable, automated process safety by ensuring immediate hermetic closure during air pressure loss. Available in metric dimensions from d75 up to d160 (DN65 to DN150), the assembly integrates fixed flanged connections conforming to EN ISO 15494 and EN 1092, allowing rigid and robust bolt-up integration into standard industrial piping networks.

The pressure-bearing body is manufactured from virgin beta-PP-H (isotactic polypropylene homopolymer), offering exceptional hydrostatic strength, high chemical resistance against aggressive acids, alkalis, and salts, and a 25-year operational design life for water at 20 degrees C. Actuation is delivered via a robust glass-fibre reinforced polypropylene (PPGF) housing containing a pre-compressed, corrosion-protected galvanised steel spring pack. The compact actuator dome incorporates an integrated optical position indicator, facilitating rapid visual inspection of the open and closed valve status under harsh plant conditions.

Engineered to handle harsh process media without compromising purity or structural integrity, the DIASTAR 025 series accommodates either high-elasticity EPDM diaphragms or chemically inert PTFE/EPDM composite diaphragms. Nominal pressure ratings span 6 bar, 8 bar, and 10 bar according to dimension and system configuration. Sourced and supplied across Europe by BigWeld as an authorised Georg Fischer distributor, these pneumatic diaphragm valves deliver maximum operating reliability, precise throttling capability, and zero external leakage in aggressive fluid management circuits.