GEMU's websites make use of cookies. If you are using the site, this means that you agree to the use of cookies. To implement personal settings, click here

GEMÜ 428

Motorized butterfly valve

  • Description
  • Features
  • Technical specifications
  • Accessories

The GEMÜ 428 butterfly valve has a low maintenance motorized quarter turn actuator. A manual override and an optical position indicator are integrated as standard.

  • Low weight
  • ATEX version available as an option
  • Various seal materials available
  • Connection: Threaded socket
  • Actuator: Motorized
  • Body material: 1.4581; CW617N (brass)
  • Max. operating pressure: 10 bar
  • Max. media temperature: 100 ° 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

00:27 min
3609 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.