Examples of usage of AVK butterfly valves with fixed liner

Centric butterfly valves with fixed liner

Centric butterfly valves with fixed liner – wafer, lug and double flanged AVK
Our fixed liner butterfly valves are among the very few of its kind and offer superior advantages.
An outstanding seating concept is the heart of the valve. The rubber is vulcanized directly on the valve body forming a permanent bond with an optimal rubber shore hardness. Consequently, there is no risk of deformation or dislocation of the liner. The valves are therefore suitable even under vacuum conditions.
The disc has a profiled sealing edge which requires minimal deformation of the liner to achieve a tight sealing. This gives less wear of the liner and low operating torques.

AVK series 75 centric butterfly valve with fixed liner
Series 75 butterfly valve from AVK
Design features of AVK centric butterfly valve with fixed liner
• Ductile iron body with coating externally, 350 microns coating, RAL 5017
• Both shafts carried by low friction bearings
• Drive shaft and disc are pinned together for safe operation
• Body and liner are bonded together to ensure high durability
• Stream lined disc design
• Two bearings and an O-ring at the top as backup sealing

Wafer, lug, double flanged butterfly valve - with any type of actuation
• Dimensions: DN40-2000 
• Valve function: Isolating or regulating 
• Actuation: Lever, wormgear, pneumatic and electrical actuators 
• Materials: Shaft of stainless or duplex steel, disc of stainless or Epoxy coated ductile iron, and liner of EPDM (for use with drinking water or high temperatures) or NBR

Where are centric butterfly valves with fixed liner used?
Fixed liner butterfly valves can be used under vacuum conditions as there is no movement and wear of the liner. Furthermore, the fixed liner valve is suitable for high flow velocities and high operating cycles e.g. open/close every few seconds. Fixed liner butterfly valves are typically used above ground, but the double flanged types are also suitable for below ground installations.

The centric butterfly valve with fixed liner can be used in a number of applications within water and wastewater treatment, fire protection and gas supply.

• Water: water treatment, water distribution, pumping installations, water transmission and HVAC
• Wastewater treatment: aeration systems, clean wastewater, filter installations, pumping installations and membrane installations
• Fire protection: indoor and outdoor
• Gas supply: natural gas and flare gas