Coal dust dampers are used in pipings of coal fired power plants between mills and burners. The purpose of these dampers is to shut-off individually the coal feeding line upstream the burner when the corresponding mill is out of service.
The coal dust dampers are of heavy duty design with an optimised flow pattern to prevent deposit formation. In opened position the damper flap is positioned completely out of the dust stream which results in full orifice cross section for less pressure drop. 

Application areas
  • Safety damper in coal dust pipes on the basis of DIN EN 12952-9 “Requirements for firing systems for pulverized solid fuels”
Nominal size: DN 150 to DN 800
Operating pressure: max. 0.5 bar g
Operating temperature: max. + 300°C

  • Completely unblocked flow cross section
  • Reliable shut-off of the medium due to robust seat sealing system
  • Shaft sealing certified in acc. with the Clean Air Guidelines (TA-Luft) for full tightness towards the exterior
  • Very short switching times compared to simple shut-off valves
When in its closed position, the flap plate is pressed onto the flap seat by the drive shaft and the internal lever, ensuring dust-tight shut-off. When the flap is opened, the flap plate is moved around 90° and unblocks the entire flow cross section. In this position the flap plate does not interfere with the flow.

Technical features
Valve body: Welded steel construction with inspection opening for service and maintenance when the valve is installed
Seat sealing system: Alternatively metallic sealing made of stainless steel, or soft sealing
Shaft sealing: Primary and secondary double O-ring sealing system optimised for the respective application, with test connection G 1/8
Actuator type:
  • Manually actuated by means of a self-locking gear box
  • Electric actuator with gear box
  • Pneumatically driven rotary drive, double or single acting, with spring reset (preferably for short positioning times)
Process connection: Alternatively with welding ends or flange connection, both available in EN and ANSI design
Special features:
  • Optionally available with internal special hard-facing for wear protection, or with ceramic lining
  • Optionally available with exchangeable seat ring
  • Optionally available with anti-surge protection according to NFPA 85
  • Optionally designed for operating temperatures of up to 400°C