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GEMÜ R690

Pneumatically operated diaphragm valve

  • Description
  • Features
  • Technical specifications
  • Accessories

The GEMÜ R690 2/2-way diaphragm valve has a low maintenance membrane actuator and is pneumatically operated. Normally Closed (NC), Normally Open (NO) and Double Acting (DA) control functions are available. The High-Flow valve body provides compact dimensions at high flow rates.

  • Same mounting height planes over multiple nominal sizes
  • Compact plant design due to flow optimised valve bodies
  • Reduced control air consumption
  • Varied optional accessories for measurement and control
  • Connection: Flange; Spigot; Union end
  • Actuator: Pneumatic
  • Body material: ABS; Inliner PP-H, grey / outliner PP, reinforced; Inliner PVDF / outliner PP, reinforced; PP (GF); PVC-U; PVDF
  • Conformities
  • Max. operating pressure: 10 bar
  • Max. media temperature: 80 ° 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''); DN 65 (2 1/2''); DN 80 (3''); DN 100 (4'')
  • Control valve

Fitting Accessories

Product video

How diaphragm valves with plastic valve bodies work

00:44 min
335 Views
Online since 16.09.2015
Deionization of boiler feed water using an ion exchanger

Product applications

Deionization of boiler feed water using an ion exchanger

In steam boiler systems, salts that have dissolved in the water lead to corrosion and deposits. To avoid corrosion and deposits, depending on the operational mode and design of the steam generator, there are important requirements regarding the quality of the boiler feed water. In a deionization system, the salts that have dissolved in the water are removed using ion-exchange resins. These salts are dissociated, i.e. in positive (cations) and negative particles (anions), and as a result, a so-called desalination line is set up as follows: cations exchanger – CO2 degasifier – anions exchanger – mixed-bed fi lter. Moreover, for the installation to operate properly, a regeneration station and neutralization are required.