Check valve 561 PVDF

  Datasheet (PDF)

The Georg Fischer SYGEF Standard check valve type 561 with fixed flanges is an engineered non-return valve designed for demanding industrial chemical processing, ultrapure water systems, and aggressive media distribution. Built entirely without metallic internal components, the valve utilizes a gravity and backpressure-actuated flow-optimized return cone to reliably prevent reverse flow in vertical piping runs. The double-guided cone geometry ensures stable, vibration-free hydrodynamic operation even under elevated flow velocities, minimizing pressure loss and turbulence across the flow channel. Tight bi-directional isolation against reverse flow is reliably initiated at a minimum water column of 2 meters, backed by high-resilience FKM elastomeric seals that resist swelling and chemical attack. Constructed from pure, unpigmented polyvinylidene fluoride (PVDF), the assembly demonstrates outstanding thermal and chemical stability across a continuous operating temperature envelope from -20 degrees C to 140 degrees C, maintaining superior mechanical strength and creep resistance under a nominal pressure rating of 16 bar. Factory-integrated fixed metric flanges provide a rigid, structurally stable flanged interface with face-to-face dimensions conforming to EN 558-1, matching the compact installation footprint of standard type 546 ball valves for seamless integration into modular process lines. The corrosion-resistant thermoplastic housing allows straightforward servicing and component replacement, offering uncompromising operational reliability in aggressive chemical delivery, pharmaceutical purified water, demineralized water loops, and heavy industrial processing applications where spring fatigue and metallic contamination must be eliminated.