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GEMÜ 491 Edessa

Pneumatically operated butterfly valve

  • Description
  • Features
  • Technical specifications
  • Accessories

The GEMÜ 491 Edessa PTFE lined butterfly valve has a metal actuator and is pneumatically operated. The "Normally Closed", "Normally Open" and "Double Acting" control functions are available. Disc and shaft are one piece, body and liner are available in different designs. The butterfly valve is available in nominal sizes DN 25 to 1050 (1½"–36"), in the standardized installation lengths: ISO 5752/20 | EN 558-1/20 | API 609 category A (DIN 3202 K1) and wafer and lug body versions available.

  • Suitable for chemically corrosive media
  • High-quality selection of materials can be combined in different ways
  • High level of plant reliability thanks to one-piece shaft and spring-washer-supported seal system
  • Long service life thanks to shaft bearings and special disc and liner geometry
  • Optional accessories are installed, set and tested so they are ready for operation
  • Connection: Flange (lug); Flange (wafer)
  • Actuator: Pneumatic
  • Seal material
  • Body material: 1.4404, block material; EN-GJS-400-18-LT, SG iron material; S355J2 + N, cast steel material; VE Duroplast, reinforced
  • Conformities: ATEX; EAC; FDA; SIL; TA Luft (German Clean Air Act); USP
  • Max. operating pressure: 10 bar
  • Max. media temperature: 200 ° C
  • Min. media temperature: -20 ° C
  • Nominal sizes: DN 40 (1 1/2''); DN 50 (2''); DN 65 (2 1/2''); DN 80 (3''); DN 100 (4''); DN 125 (5''); DN 150 (6''); DN 200; DN 250; DN 300; DN 350; DN 400; DN 450; DN 500; DN 600

Fitting Accessories

Product video

How butterfly valves work

00:38 min
1461 Views
Online since 16.09.2015
More videos
GEMÜ valves in plants for modern sludge recycling
Further applications

Product applications

GEMÜ valves in plants for modern sludge recycling

Large sewage clarification plants, such as the urban drainage department of Stuttgart, recycle their sludge in mono-combustion plants. GEMÜ valves in the plant design ensure the safety and reliability of processes when it comes to drying sludge.