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GEMÜ butterfly valves

Butterfly valves in plastic and metal

  • Areas of application and industrial sectors
  • Valve type
  • Technical data

Butterfly valves: Areas of application and industrial sectors

GEMÜ butterfly valves are primarily used in industrial applications and the chemical industry, as well as the fields of water supply and water/waste water treatment. The concentric and single-eccentric designs are available as standard. However, the double-eccentric and triple-eccentric shut-off valves are also available for projects on request. Use of matched control components such as position indicators, positioners and process controllers allows GEMÜ butterfly valves to also be used in control circuits.

Butterfly valves: Valve type

The butterfly valve comprises a ring-shaped body in which a ring-shaped elastomer seat/liner is inserted. A washer guided through a shaft swings through a 90° rotary movement into the gasket. Depending on the version and nominal size, this enables operating pressures of up to 25 bar and temperatures up to 210 °C to be shut off. Most often, these valves are used for mechanically pure liquids, but can also be used in the right material combinations without posing any problems for slightly abrasive media or gases and vapours. 

Due to the large variety of materials, the butterfly valve is universally compatible, for example with countless industrial applications, water/drinking water treatment, coastal and offshore sectors. The butterfly valve is also often a cost effective alternative to other valve types, where there are no stringent requirements regarding switching cycles, hygiene or control accuracy. In large nominal sizes of greater than DN 150, it is often the only shut-off valve that is still viable. For more stringent demands with respect to chemical resistance or hygiene, there is the possibility of using a butterfly valve with a seat made of PTFE or TFM. In combination with a PFA encapsulated stainless steel disc, it is suitable for highly aggressive media in the chemical or semiconductor industry; and with a polished stainless steel disc, it can also be used in the foodstuff or pharmaceutical sector.

For all the valve types specified, GEMÜ offers numerous customized accessories for automation and process optimization. Electr. position indicator, position and process controllers, sensor systems and measurement devices, are easily and quickly fitted, adjusted and integrated in the existing process control technology. 

Butterfly valves: Technical data

OperationManual, pneumatic, motorized
ConnectionsUnion ends, threaded sockets, butt weld spigots
Operating pressure0 - 16 bar
Body materialsMetal: Aluminium, stainless steel, cast iron, brass, SG iron, cast steel
Plastic: PES, PP, PVC
Media temperatur-60 - 210 °C
Nominal sizesDN 15 - 1600
GEMÜ 423
Union end
PVC-U, grey
6 bar
60 ° C
DN 15 (1/2''); DN 20 (3/4''); DN 25 (1''); DN 32 (1 1/4''); DN 40 (1 1/2''); DN 50 (2'')
GEMÜ 428
Clamp; Spigot; Threaded connection
1.4408, investment casting material; CW614N, brass; CW617N, brass
10 bar
120 ° C
-20 ° C
DN 15 (1/2''); DN 20 (3/4''); DN 25 (1''); DN 32 (1 1/4''); DN 40 (1 1/2''); DN 50 (2'')
GEMÜ 488
Flange (U section); Flange (lug); Flange (wafer)
EN-GJS-400-15, SG iron material
16 bar
150 ° C
-10 ° C
DN 25 (1''); DN 40 (1 1/2''); DN 50 (2''); DN 65 (2 1/2''); DN 80 (3''); DN 100 (4''); DN 125 (5''); DN 150 (6''); DN 200; DN 250; DN 300; DN 350
GEMÜ 498
Flange (lug); Flange (wafer)
1.4404, block material; EN-GJS-400-18-LT, SG iron material; S355J2 + N, cast steel material; VE Duroplast, reinforced
10 bar
200 ° C
-20 ° C
DN 40 (1 1/2''); DN 50 (2''); DN 65 (2 1/2''); DN 80 (3''); DN 100 (4''); DN 125 (5''); DN 150 (6''); DN 200; DN 250; DN 300
PP, reinforced
10 bar
90 ° C
5 ° C
DN 50 (2''); DN 65 (2 1/2''); DN 80 (3''); DN 100 (4''); DN 125 (5''); DN 150 (6''); DN 200; DN 250; DN 300
Flange (U section); Flange (lug); Flange (wafer)
1.4408, cast stainless steel material; EN-AC-46100, aluminium casting material; EN-AC-47100, aluminium casting material; EN-GJS-400-15, SG iron material; EN-GJS-400-18-LT, SG iron material; S275JR, cast steel material
16 bar
210 ° C
-60 ° C
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''); DN 125 (5''); DN 150 (6''); DN 200; DN 250; DN 300
Flange (lug); Flange (wafer)
EN-GJS-400-15; EN-GJS-400-18-LT
16 bar
150 ° C
-10 ° C
DN 50 (2''); DN 65 (2 1/2''); DN 80 (3''); DN 100 (4''); DN 125 (5''); DN 150 (6''); DN 200; DN 250; DN 300

Uranium removal and partial deionization at the Trollmühle Waterworks

GEMÜ butterfl y valves at the Trollmühle Waterworks - Uranium removal and partial deionization using Uranex® and Carix® procedures
Currently, the waterworks at the Trollmühle water supply authority in Windesheim near Bingen am Rhein supply approximately 43,000 people in 14,000 households with 2.2 million m³ drinking water per year. At peak times, this means a daily dispensing volume of up to 8500 m³.