Baffle Gate (Baffle Valve)

About this part

Damper gates (damper valves) are manufactured by Lianyungang Huaneng Power Auxiliary Equipment Co., Ltd. using imported technology. They are used in the inlet, outlet, or bypass flues of absorption towers in flue gas systems, or in flue gas denitrification and dust removal systems.  Desulfurization Flue gas damper gates typically employ a louver-type double-layer damper structure. When closed, sealing air is introduced between the double-layer dampers to achieve airtight sealing and isolate the flue gas.

Damper valves can be classified by shape into square single-shaft double-damper gates and circular single-shaft double-damper gates; by driving method into electric single-shaft double-damper gates and pneumatic single-shaft double-damper gates; by application location into FGD inlet raw flue gas damper gates, FGD outlet clean flue gas damper gates, FGD bypass flue gas damper gates, FGD booster fan inlet damper gates, and FGD booster fan outlet damper gates; and by material into carbon steel single-shaft double-damper gates, stainless steel single-shaft double-damper gates, and nickel-based alloy single-shaft double-damper gates.

Performance Characteristics of Flue Gas Damper

• The flue gas damper adopts a single-shaft driven double-louvered damper structure. A sealing chamber for introducing sealing air is designed between the double-layer blades. Sealing air at a pressure higher than the flue gas pressure is introduced into the damper, creating a sealing air isolation layer between the double-layer dampers, thus blocking the passage of flue gas.
• The opening and closing time of the flue gas damper is ≤60S (can be selected according to user requirements).
• The damper valve is designed with a linkage mechanism on the outside, allowing several blades to open or close synchronously. The shaft seal device is separated from the rolling bearing, making adjustment and maintenance convenient, and eliminating bearing corrosion defects.
• The double-louvered flue gas damper has a reasonable design structure, good blade rigidity, and stable and reliable operation. The sealing type of the louvered damper blades is elastic sealing or air sealing.
• The flue gas damper can be selected with various driving methods: electric or pneumatic.
• The air sealing fan and the damper plate are controlled by a mechanical linkage mechanism, ensuring safety and reliability.

Structural Characteristics of Flue Gas Damper

The flue gas damper mainly consists of a frame, blades, sealing strips, main shaft, bearings, shaft seals, crank linkage mechanism, actuator, and sealing air system (auxiliary system). The frame produced by Huaneng is formed by steel plate molding or welded from shaped steel. The blades are formed by steel plate molding and welding. Special elastic sealing structures are provided between the blades and between the blades and the frame. The blades are made into a hollow cavity type. When the blades are in the closed position, a mechanical sealing barrier is first formed on the flue gas cross-section, and then sealing air with a pressure higher than the working medium pressure is introduced to form a high-pressure sealing air curtain, completely separating the front and back of the blades and ensuring 100% isolation effect.

Huaneng's damper uses a special sealing structure and special bearings at the shaft journal. The special sealing structure has good sealing performance, no leakage, high temperature resistance, and corrosion resistance. The special bearings have automatic self-aligning and automatic compensation functions. IV. Technical Parameters of Flue Gas Desulfurization Damper:

• Flue duct cross-section: W (width) × H (height) × L (thickness);
• Applicable medium: Hot and cold flue gas;
• Design temperature resistance: ≤300℃;
• Design pressure: ±8500Pa;
• Internal and external leakage rate of flue gas: “0”
• Driving method: Electric or pneumatic;
• Power supply and control requirements: Selected by the user. 
• Applicable medium: Hot and cold flue gas;
• Design temperature resistance: ≤300℃;
• Design pressure: ±8500Pa;
• Internal and external leakage rate of flue gas: “0”
• Driving method: Electric or pneumatic;
• Power supply and control requirements: Selected by the user.

Quality documentation included

• Dimensional inspection report (CMM / profile projector) for critical features
• Material certificate with heat number traceability
• Surface finish and hardness records where specified
• Photographic packing record before shipment