Valves
- Accessories
  - Accessories
    
    A large range of accessories is available to round off the GEMÜ product range. These include stroke limiters and optical position indicators for valves, assembly accessories, mounting kits for position indicators and controllers, control air adapters and NAMUR mounting brackets, plugs and cable connectors, travel sensors for controllers and many other items.
- Actuators
  - Actuators
    
    Alongside valve assemblies, GEMÜ also offers linear and quarter-turn actuators for adaptation to valve bodies from other manufacturers. These allow, for example, high-quality valve actuators to be fitted to many butterfly and ball valve bodies using connection flanges according to ISO 5211. There is also a suitable actuator in the range for globe and diaphragm valves.
- Ball valves
  - Ball valves
    
    GEMÜ ball valves can be used in many different applications. However, they are primarily used in industrial processes, in the fields of water supply and water/waste water treatment. In addition to this, GEMÜ plastic ball valves are successfully used in the chemical industry. Alongside valves with a straight through body (2/2-way valve), T valves (3/2-way valve) are also available. Accessories, such as seal adjusters and stroke limiters, proximity switches, optical position indicators and electrical position indicators, round off the ball valve portfolio.
- Butterfly valves
  - Butterfly valves
    
    GEMÜ butterfly valves are primarily used in industrial processes and the chemical industry, as well as the fields of water supply and water/waste water treatment. The concentric design is available as standard. However, the double-eccentric and triple-eccentric shut-off valves are also available for projects on request. Depending on the application, appropriate accessories are also available. The use of matched control components such as positioners and process controllers allows GEMÜ butterfly valves to also be used in control circuits.
- Check valves
  - Check valves
    
    Check valves are used in virtually all types of plants, as well as numerous processes and applications in all industries. GEMÜ offers various types of check valves.
- Diaphragm globe valves
  - Diaphragm globe valves
    
    Diaphragm globe valves from GEMÜ are suitable both for opening/closing applications and for control and dosing applications. The PTFE diaphragms used reliably isolate the medium from the actuator. The valves are easy to clean and, in comparison with valves with bellows, have significantly reduced deadlegs. A pretensioning element included in the actuator guarantees external leak tightness, even with temperature fluctuations and settling of the plastic parts. The valves are available both with straight through bodies and as multi-port valve block systems.
- Diaphragm valves
  - Diaphragm valves
    
    As they are available with such a large number of body and seal materials, GEMÜ diaphragm valves are used successfully in many different applications. Depending on the application, various actuation types, body materials and connections are available.
- Fittings and tubing
  - Fittings and tubing
    
    GEMÜ offers over 100 different fitting options for the production of semiconductors, LEDs, high-purity media, microchips and solar cells with the most common connections in the market. The product range has been expanded to include high-quality tubes for applications with high-purity media.
- Globe valves
  - Globe valves
    
    Globe valves are ideal for fast cycle duties, high temperatures and control applications. Although they are often used for steam control and in the field of water/waste water treatment, they can handle the most diverse of applications in industrial processes, and also in sterile and hygienic applications in the pharmaceutical, food and biotechnology industries. GEMÜ offers globe valves in both straight seat and angle seat designs. Depending on the valve type, both 2/2-way bodies and 3/2-way bodies are available.
- Pilot solenoid valves
  - Pilot solenoid valves
    
    GEMÜ supplies pilot valves for pneumatically operated valves, cylinders and other process components. These stand out thanks to their robust and durable design and precise air dosing.
- Single-use valve components
  - Single-use valve components
    
    Single-use valves are used if it is crucial to avoid cross contamination or if a simplified plant design is required. The GEMÜ product range comprises single-use diaphragm valves with manual or pneumatic actuators. The single-use valve body is disconnected from the actuator and disposed of after it is used once. In contrast, the actuator remains in the system for multiple use.
- Solenoid valves
  - Solenoid valves
    
    Solenoid valves are designed for fast cycle duties and are particularly suitable for dosing applications. They are primarily used in the widest range of general industrial applications.
- Strainer
  - Strainer
    
    Strainers are used to filter out contaminants in fluid flows. Depending on the flowing medium, different mesh sizes and materials are available for the filter insert.
- Tools
  - Tools
    
    Not every installation and repair step can be carried out with standard tools. However, so that this can be done quickly and simply, GEMÜ provides a selection of special tools for valve assembly or wearing part replacements, for example.
Measurement & control
- Accessories
  - Accessories
    
    A large range of accessories is available to round off the GEMÜ product range. These include stroke limiters and optical position indicators for valves, assembly accessories, mounting kits for position indicators and controllers, control air adapters and NAMUR mounting brackets, plugs and cable connectors, travel sensors for controllers and many other items.
- Electrical position indicators and combi switchboxes
  - Electrical position indicators and combi switchboxes
    
    Pneumatically operated quarter-turn valves and valves with a linear actuator are often used in conjunction with electrical position indicators. Depending on the device type, microswitches or proximity switches are used. They enable reliable end position feedback and can be equipped with a fieldbus connection upon request (e.g. AS-Interface, DeviceNet, etc.).
- Fittings and tubing
  - Fittings and tubing
    
    GEMÜ offers over 100 different fitting options for the production of semiconductors, LEDs, high-purity media, microchips and solar cells with the most common connections in the market. The product range has been expanded to include high-quality tubes for applications with high-purity media.
- Flowmeter
  - Flowmeter
    
    GEMÜ offers various valve designs for flow measurement systems:
- Positioners and process controllers
  - Positioners and process controllers
    
    GEMÜ's product range for process automation of valves includes 3-point controllers to control the position of motorized valves and electro-pneumatic positioners for pneumatic valves with quarter-turn or linear actuators.
- Pressure and temperature measurement devices
  - Pressure and temperature measurement devices
- Pressure control valves
  - Pressure control valves
    
    GEMÜ pressure control valves are used in plants that require a constant operating pressure or system pressure. They control the upper pressure limits, prevent pressure peaks and/or balance out pressure fluctuations. Depending on the function, three different designs are available.
Spares
- Diaphragms
  - Diaphragms
    
    A diaphragm is the central sealing element in a diaphragm valve. Only the diaphragm and the valve body are in direct contact with the flowing medium. In addition, it ensures external hermetic sealing. Diaphragm production takes place within the GEMÜ group and with certified suppliers. Distinctions are made between soft elastomer and PTFE diaphragms. Diaphragms for weir-type diaphragm valves have the tried and tested GEMÜ seal system up to a nominal size of DN 100.
- Replacement actuators for diaphragm valves
  - Replacement actuators for diaphragm valves
    
    For fast and simple replacement of actuators, GEMÜ permanently has an appropriate selection of different replacement actuators in stock.
- Replacement actuators for globe valves
  - Replacement actuators for globe valves
    
    For fast and simple replacement of actuators, GEMÜ permanently has an appropriate selection of different replacement actuators in stock.
- Spare parts kits for globe valves
  - Spare parts kits for globe valves
    
    All valves are subject to a certain degree of wear during their lifetime. For the replacement of these components or for repair purposes, the range includes various spare parts kits.
Applications

687 20D 137 21FRN

Diaphragm valve, pneumatic

Item number:		88846829
Description

Type	687	Diaphragm valve, pneumatically operated, plastic actuator, stainless steel distance piece
DN	20	DN 20
Body configuration	D	2/2-way body
Connection type	1	Threaded socket DIN ISO 228
Valve body material	37	1.4408, investment casting
Diaphragm material	2	NBR
Control function	1	Normally closed (NC)
Actuator version	FRN	Operator size FRN
Diaphragm size	25	Diaphragm size 25

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Description Features Tender specifications

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.

Hermetic separation between medium and actuator
CIP/SIP capable
Wide range of adaptation options for add-on components and accessories
Suitable for particulate and abrasive media
Stainless steel body suitable for corrosive environments
Wide range of adaptation options for add-on components and accessories

Tender specifications for

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