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GEMÜ 491

Pneumatically operated butterfly valve

  • Description
  • Features
  • Technical specifications

Die GEMÜ 491 PTFE seal butterfly valve has a metal actuator and is pneumatically operated. The disc and shaft are one piece; the body and liner are available in different designs. The butterfly valve is available in nominal sizes DN 40–900 (1½"–36") and in wafer and lug body versions.

  • Suitable for isolating and control functions with gaseous and liquid media
  • Seal material TFM™ (FDA 21CRF 177.1550)
  • Installation length acc. to ISO 5752/20, EN 558-1/20, JIS 10K
  • ATEX version available as an option
  • TA-Luft compliant
  • Extensive applications using a variety of materials
  • Connection: Flange
  • Actuator: Pneumatic
  • ATEX
  • Explosion protection
  • Body material: ; 1.4301, stainless steel; EN-GJS-400-18-LT; S355J2G3 steel
  • 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

Product video

How butterfly valves work

00:27 min
4048 Views
Online since 16.09.2015
Innovative methods for freeze-drying pharmaceutical products

Product applications

Innovative methods for freeze-drying pharmaceutical products

Many pharmaceutical manufacturing procedures are based on bio-technological processes. Often, their molecular structure is extremely complex and their liquid form is unstable, which is why many bio-pharmaceuticals cannot be stored directly. Freeze-drying is the gentlest procedure for conserving the active ingredient solution. Because of critical operating conditions the butterfly valve GEMÜ 490 is particularly important.