Pneumatic Diaphragm Valve DIASTAR Six PVC-C FC PN6

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The Georg Fischer DIASTAR Six PVC-C pneumatic diaphragm valve provides reliable fail-safe-to-close (FC) automated flow isolation and throttling in demanding industrial piping systems. Engineered by Georg Fischer and supplied by BigWeld, this valve combines an agate grey post-chlorinated polyvinyl chloride body with a high-grade EPDM diaphragm. Operating with an internal spring set, the fail-safe-to-close actuator ensures tight shut-off upon pilot air loss, protecting downstream equipment and lines against uncontrolled chemical flow.

The optimized linear flow geometry of the DIASTAR Six provides double the flow capacity of previous valve generations, substantially decreasing pressure drops and operational energy demands. Its compact pneumatic actuator features a 90 degrees indexable pilot air connection, enabling installers to rotate the air port for tidy pneumatic tubing routing in tight pipe racks. Routine maintenance is simplified by a heavy-duty central housing nut that replaces traditional four-bolt bonnets. This thread connection eliminates uneven bolt torque and allows fast diaphragm servicing without removing the valve body from the line.

Constructed from industrial-grade PVC-C (RAL 7038), the valve offers superior resistance to aggressive acids, bases, and salt solutions at operational temperatures up to 80 degrees Celsius. Rated for a working pressure of 6 bar, this series covers metric pipe diameters from d25 to d63 (DN20 to DN50). The valve body is equipped with metric solvent cement spigots built to EN 558 face-to-face installation lengths, allowing direct integration into industrial manifolds.

Widely deployed in chemical processing lines, industrial water treatment, electroplating baths, and cooling circuits, the valve delivers long-term process reliability. As an authorised Georg Fischer distributor, BigWeld supplies genuine industrial components across Europe with full technical backing.