Shut off damper

Function

Shut off damper is used to allow or deny passage of fluids in air or flue duct by switching between “fully closed” and “fully open” at 0° or 90° position. It can’t be used to adjust volume or pressure.

Structure

Shut off damper consists of framework, blades, sealing plate, spindle, bearing, lever, actuator, etc.

• Elastic sealing plates between blades, blade and framework are equipped to ensure 99% air tight performance.
• Louver in airfoil shape are designed to minimize pressure loss to the whole system when damper is open. Rigid structure to avoid deflection and warping.
• Blade spindle is connected with framework by self aligned and self compensating bearing, which makes shut off damper rotate smoothly, no jamming at hot status.
• Bearing journal is stuffed with heat resistant packings to make sure no leakage.
• Framework are carefully fabricated with structural steel to avoid deformation in various condition.

Features

1. Optional alloy material for corrosive fluids to extend service life.
2. Manual operated, motorized, pneumatic driving design provided for choice.
3. Remote control by DCS available.
4. Over torque protection and limit switch.
5. Easy switch between manual or electrical/pneumatic operation.
6. Driving torque 50 to 10000N*m. Dimension 300*400mm to 11000*6600mm.

Application

Shut off damper is widely used in following location in thermal power plant:

• Inlet and outlet of flue gas & combustion air at air preheater.
• Flue gas duct between ID fan and dust collector.
• Inlet and outlet of FD fan and primary air fan.
• Hot/cold primary air inlet before coal pulverizer.
• FGD flue gas inlet/outlet, bypass duct.