Pneumatic Diaphragm Valve DIASTAR Six ABS FC PN6 d25-d63

  Datasheet (PDF)

The Georg Fischer DIASTAR Six ABS pneumatic diaphragm valve is engineered for automated flow isolation and throttling in industrial plastic piping systems. Operating with a Fail-Safe-to-Close (FC) pneumatic actuator, the valve utilizes heavy-duty internal spring packs to shut off line media safely upon loss of pilot air supply. Rated for nominal working pressures up to PN6 (6 bar at 20 degrees Celsius), this model covers pipe diameters from d25/DN20 up to d63/DN50. The valve body is precision-moulded from impact-resistant Acrylonitrile Butadiene Styrene (ABS) in RAL 7001 gravel grey, coupled with a durable EPDM diaphragm that guarantees bubble-tight shutoff even when handling media carrying suspended mineral particulates.

A primary mechanical innovation of the DIASTAR Six is the central housing nut assembly, which replaces conventional multi-bolt bonnet patterns. This structure applies constant, symmetrical clamping force along the entire sealing bead of the EPDM diaphragm, eliminating localized stress points and prolonging elastomer working life. True union ends with metric solvent cement sockets permit rapid radial removal from the piping network without spreading adjacent pipes, designed for seamless jointing using Tangit ABS cement and primer.

The actuator housing is fabricated from glass-fibre reinforced polypropylene (PP-GF), providing high structural rigidity and exceptional resistance to corrosive atmospheric conditions. An integrated G 1/8 inch pneumatic control port can be rotated in 90 degrees increments during assembly, allowing flexible air hose routing in restricted manifolds. The hydrodynamic internal flow path delivers up to double the flow capacity of earlier diaphragm valve versions, minimizing system pressure drop. Threaded stainless steel base inserts provide robust anchor points for pipe brackets.

Engineered specifically for closed-circuit cooling systems, chilled water loops, and industrial water treatment installations, the DIASTAR Six ABS FC valve prevents limescale build-up and electrochemical corrosion, ensuring continuous process reliability.