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GEMÜ 428

Motorized butterfly valve

  • Description
  • Features
  • Technical specifications
  • Accessories

The GEMÜ 428 soft seated butterfly valve made from stainless steel or brass is motorized. A manual override and an optical position indicator are integrated as standard. With its rounded and polished disc edges, the butterfly valve is optimized for frequent cycle duties. The surface of the butterfly valve can be further finished.

  • Suitable for vacuum applications and low temperatures
  • High-quality butterfly valve made from stainless steel or brass
  • Available in small nominal sizes
  • Compact and robust body
  • Compact selection of actuators is possible
  • Connection: Clamp; Spigot; Threaded connection
  • Actuator: Motorized
  • Seal material
  • Body material: 1.4408, investment casting material; CW614N, brass; CW617N, brass
  • Conformities: CSA; EAC; FDA
  • Max. operating pressure: 10 bar
  • Max. media temperature: 120 ° C
  • Min. media temperature: -20 ° C
  • Nominal sizes: DN 15 (1/2''); DN 20 (3/4''); DN 25 (1''); DN 32 (1 1/4''); DN 40 (1 1/2''); DN 50 (2'')

Fitting Accessories

Product video

How butterfly valves work

00:38 min
869 Views
Online since 16.09.2015
Dosing station for dyeing auxiliaries

Product applications

Dosing station for dyeing auxiliaries

Indigo belongs to the group known as vat dyes. These dyes are typified by the fact that they do not form a chemical compound with the yarn, instead adhering to its surface as a surrounding pigment. Hydrosulphite (dithionite) is used as an auxiliary material when dying cotton with indigo (e.g. denim). It turns the water-insoluble blue colour indigo into a water soluble light-yellow leucoindigo (indigo white). This process is referred to as vatting.