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GEMÜ 687

Pneumatically operated diaphragm valve

  • Description
  • Features
  • Technical specifications
  • Accessories

The GEMÜ 687 2/2-way diaphragm valve has a low maintenance plastic membrane actuator and is pneumatically operated. The valve has a metal distance piece. Normally Closed (NC), Normally Open (NO) and Double Acting (DA) control functions are available.

  • The modular actuator system permits a variety of options to be used such as tank bottom valves, T valves, sampling valves, multi-port valves and tandem welded configurations
  • Optional flow direction and installation position
  • Connection: Clamp; Flange; Spigot; Threaded socket; Threaded spigot
  • Actuator: Pneumatic
  • ATEX
  • Explosion protection
  • Body material: 1.4408, PFA lined; 1.4408, investment casting; 1.4435, forged body; 1.4435, investment casting; EN-GJS-400-18-LT (GGG 40.3), PFA lined; EN-GJS-400-18-LT (GGG 40.3), PP lined; EN-GJS-400-18-LT, hard rubber lined
  • Max. operating pressure: 10 bar
  • Max. media temperature: 100 ° C
  • Min. media temperature: -10 ° C
  • Nominal sizes: DN 10 (3/8''); DN 12; 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'')
  • Pilot valve
  • Control valve

Fitting Accessories

Product video

Diaphragm replacement for GEMÜ 687 with diaphragm code 5E

05:58 min
954 Views
Online since 04.04.2018
Equipment für Separating Liquid Mixtures

Product applications

Equipment für Separating Liquid Mixtures

There are various reasons for separating liquid mixtures or for changing their ratio of mixture. Pervaporation/steam permeation (membrane filtration) enables the separation of water / solvent mixtures, the separation of liquids with similar boiling points, the dehydration of multicomponent mixtures, the displacement of equilibrium in reactions where water is released and the dehydration of organic compounds. The complete system consists of an evaporator and a membrane module. lf the liquid to be separated is a distillation product, the steam can be directly passed into the membrane module. In this application the mixture is composed of water with maximum 5 % alcohol. The equipment is located in an 'ex' area.

Product news

09.04.2018

New tutorials on replacing two-piece diaphragms

The GEMÜ training team has already published a number of videos in recent years on specific content such as replacing wearing parts.

Product news

07.10.2015

SIL assessment of GEMÜ products

Together with the independent testing organization EXIDA, GEMÜ has assessed a selection of different products in accordance with SIL.