Diaphragm valve DIASTAR ABS 025 DA double acting

The Georg Fischer DIASTAR ABS Series 025 DA double acting pneumatic diaphragm valve delivers flow regulation and tight shut-off in industrial piping networks. The body is made of ABS (acrylonitrile butadiene styrene) and sealed by an EPDM diaphragm, a combination suited to secondary cooling circuits, chilled water loops, industrial water treatment, marine systems and drinking water distribution. Integrated metric flanges to EN 1092, ISO 7005 and DIN 2501 in PN10 and PN6 patterns let the valve be bolted directly into thermoplastic pipelines without separate flange adaptors. Available sizes are 75 mm, 90 mm and 110 mm.

The double acting (DA) actuator uses control air for both the opening and the closing stroke, giving short response times, balanced thrust and consistent stroke control across varying line pressures. Unlike spring return units, it keeps full operating force in both directions without working against a return spring, which optimises compressed air consumption and reduces internal actuator wear. An optical position indicator on top of the actuator housing confirms valve status at a glance during routine plant inspections.

The streamlined ABS flow path limits turbulence and pressure loss, reaching kv values of up to 2700 l/min on the larger nominal diameters. ABS offers high impact resistance, high tensile strength and good thermal insulation in sub-zero and chilled process conditions, so the valve body stays free of sweating and external corrosion. Together with the chemical and thermal endurance of the EPDM diaphragm, the Series 025 DA handles non-abrasive fluids, treated water and common utility chemicals. Threaded metal inserts in the body provide secure structural mounting on pipe brackets and modular skids, while the flanged connection allows inline maintenance and diaphragm inspection without cutting the pipe run.

BigWeld is an authorised Georg Fischer distributor and supplies the DIASTAR 025 DA in PN10 and PN6 pressure classes with EPDM seals.