Power-Failure Quick-Opening Flue Gas Damper Valve

About this part

The implementation of a coke oven flue gas desulfurization project requires extracting flue gas from the underground flue.  A vertical Slide gate valve needs to be installed after the gas extraction point to prevent leakage or backflow of coke oven flue gas. However, in special situations such as power failure of the main flue gas fan, to ensure system safety, this vertical slide gate valve must be able to open automatically, promptly, and quickly, ensuring that the flue gas can be discharged normally through the underground flue.

Lianyungang Huaneng Power Auxiliary Equipment Co., Ltd. has specially developed a "power-off quick-opening vertical slide gate valve," also known as: quick-opening slide gate valve, quick-opening flue gas valve, quick-opening flue gas slide gate valve, coke oven underground flue slide gate valve, counterweight quick-opening valve, or coking quick-opening slide gate valve. This device can automatically, promptly, and quickly open even in the event of a power failure during system abnormalities, ensuring rapid flue gas passage and thus guaranteeing system safety.

Main Components of the Device

The power-off quick-opening vertical slide gate valve device mainly consists of two parts: the slide gate valve body and the driving device. These two parts are arranged parallel to each other and connected as a whole through a steel wire rope and pulley system. See the "Structural Diagram of the Power-Off Quick-Opening Vertical Slide Gate Valve" below for details. The slide gate valve body mainly consists of the door frame, door body, elastic linear sealing strips, and a three-way positioning guide wheel group. The driving device mainly consists of the device frame, counterweight, counterweight guide rail, damping device, shock absorption device, counterweight lifting device, locking device, quick-release device, and control system.

Technical Specifications

Working Principle

Under normal operating conditions, the damper blade is held in position by an electric or electro-hydraulic actuator. When a power failure or emergency shutdown occurs:

• Electrical energy to the actuator is interrupted

• A stored energy mechanism (spring, counterweight, or hydraulic accumulator) is released

• The damper blade opens fully within a short time

• Flue gas is safely discharged through the duct system

The opening action does not rely on external power, ensuring reliable operation during emergencies.

Main Components

A typical power failure quick-opening Flue gas damper valve consists of:

• Damper body: Designed for high-temperature flue gas environments

• Damper blade: Single or multi-blade structure for fast opening

• Actuator: Electric or electro-hydraulic type

• Energy storage unit: Spring-loaded or weight-driven mechanism

• Limit switches: Provide position feedback

• Sealing system: Metal or composite seals for normal operation

Key Features

• Automatic opening during power failure

• Fast response time for emergency conditions

• Fail-open safety design

• Suitable for high-temperature flue gas systems

• Robust structure for continuous industrial operation

Typical Applications

• Industrial boiler flue gas systems

• Thermal power plant ductwork

• Industrial furnaces and incinerators

• Flue gas desulfurization systems

• Emergency bypass or relief flue ducts

In these systems, the damper serves as a safety relief and protection device rather than a flow control component.

Technical Considerations

When specifying or designing this type of damper, the following parameters are commonly evaluated:

• Opening time under power loss

• Maximum flue gas temperature

• Duct size and pressure conditions

• Required fail-safe position

• Maintenance accessibility

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