Guillotine Dampers

Patented Bellow Seal Design – The Tightest Seal in the Industry
Exemplary Isolation in Hostile Gas and Particulate Environments

Flextech Industries’ guillotine dampers are preferred in applications where isolation (open/close operation) is critical and where services conditions can be severe. There is no “light-duty” guillotine damper.

Flextech offers two basic types of custom-engineered Warrior Series guillotine dampers: the ‘low leak’ Structural Seal design and the ‘ultra low leak’ patented Bellow Seal design.

Structural Seal Design

The Structural Steel design uses a structural steel channel frame with a structural angle on the downstream side of the blade to create the duct seal. This design is a cost-effective solution where moderate leakage rates are acceptable and the gas stream is relatively clean.

95 to 98% isolation
Low operating / maintenance costs

Patented Bellow Seal Design

The patented Bellow Seal design uses convoluted metal bellows on both the upstream and downstream side of the blade to form the seal. The Bellow Seal is a continuous-perimeter seal with no gaps or overlaps and requires that no bolting be exposed to the gas stream. The result of this patented technological advancement is an area seal with reduced leak passages, lower seal air requirements, and increased seal life expectancy. It is manufactured in both rectangular and round configurations without the need for transitions. This design is frequently used without seal for applications where ‘man safe’ isolation is not required.

High sealing efficiency for 99.5 to 99.9% isolation
Seal is 125-300% thicker than conventional leaf seal and will last considerably longer under corrosive conditions
Seal has 300% greater contact area than conventional leaf seal, eliminating the possibility of large inversion
Inverted-V leading edge
Particularly suited for applications where deposits of ash or other solids are anticipated
Externally cartridge-mounted for quick and easy removal/replacement, with single-point access. Cartridge design can be replaced in a matter of hours without scaffolding and allows for removal of sections rather than the entire seal. As a result, operating and maintenance costs are lowered.

Advantages of Flextech Guillotine Dampers

Lower pressure drop than multi-bladed louver dampers
Less space required in the duct (i.e., flange/flange)
- Guillotine - 12” to 18” f/f
- Double Louver – 36” and up f/f
Improved capability to cut through deposits of particulate in the duct
Fewer moving parts, less maintenance, and lower downtime costs

A seal air system is required for ‘man safe’ isolation. The Bellow Seal guillotine damper requires a significantly smaller seal air system than all other types of guillotine dampers.

Guillotine Applications include:

Scrubbers, Precipitators, Oxidizers, Heaters, Incinerators, Boiler Breaching, and Burner Fuel Lines

Drive Systems

Flextech offers three basic drive systems for guillotine dampers:

Dual Mining Chain and Pocket Sprocket Drive

The drive system is most commonly used in large guillotine dampers. The frame is constructed of a heavy, rolled structural channel (A36) with cross bracing and lifting lugs to withstand all drive thrusts, wind, and handling loads without additional supports. Web-mounted bearings support torsionally rigid sprocket/torque tube assemblies by utilizing high-strength, corrosion-resistant stub shafts.

Long wall mining chain and pocket sprockets are standard, providing smooth, trouble-free blade movement. The chain has no tight clearances to promote' corrosion, dirt accumulation, and subsequent binding (as conventional ‘plate and pin’ styles are subject to). The dual chains are linked by the drive tubes to ensure that the attached blade is always driven straight and its alignment is maintained when driving through uneven solid deposits. The dual-chain drive is recommended for all applications in duct sizes larger than five feet on a side/diameter, and tends to be generally more economical than the jackscrew drive in sizes exceeding five feet.

Positive positioning of the blade in both opening and closing directions
Infrequent chain adjustment due to pre-stretching during manufacture.
Even tracking of the blade despite driving it through uneven solid deposits
Designed to withstand the maximum output of the actuator
Sealed bearings are web-mounted for proper support of torque tubes’ secondary reducers

Rack and Pinion Drive

The rack and pinion drive is a more economical drive system for small- to mid-size guillotine dampers. The torque is transferred directly to the blade from the drive pinion via a rack that is cut into the blade edges. The holes are located so that, in the closed position, they are covered by path.

Suitable for dampers smaller than five feet on a side
Positive positioning of the blade in both opening and closing direction

Linear Cylinder Drive

The linear cylinder drive is the most economical drive system for smaller guillotine dampers. It offers positive positioning of the blade in both opening and closing directions. It is provided with a standard four-way solenoid valve and end cushions for two-position operation.

Suitable for dampers smaller than five feet on a side
Positive positioning of the blade in both opening and closing direction

Actuators

Flextech offers three actuator systems for its guillotine dampers:

Manual

The manual handwheel and chainwheel actuators are available for direct drive
applications on dual chain and rack and pinion systems. All are designed so that
the actuation load does not exceed 80 pounds. They are also self-locking.

Pneumatic

The pneumatic linear cylinder is an 80–120 psig source with sufficient volume to operate reliably.

Electric

The electric actuator may be used to drive the dual chain and rack and pinion systems. It consists of a self-locking worm gearbox, limit and overtorque protection, and a manual override handwheel. Electric actuators are available in a standard source voltage of 460v/ 3ph/60hz z (other voltages available).