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Circular Fire Dampers FD-EI120S

According to the tests performed in the Czech Republic, we are pleased to announce that starting March 15, 2019, SBI Steel Industry will begin production of circular fire dampers CE certified with fire resistance 120 min.

Please find below the technical data for the product.

For our offers, delivery dates, technical data and additional information, our team is at your service.

Circular Fire Dampers FD-EI120S


The circular fire dampers are designed for insulating the wall bushings among compartments in the event of fire.
They prevent fire spreading through the ductwork system. The fire dampers are mounted in the ventilation ducts passing through the walls that define the fire compartments.
The fire dampers close automatically at the occurrence of high temperatures through a spring or an actuator.

Our company produces circular fire dampers for the insulation of gaps among the fire compartments.

  • Tested according to EN 1366-2:2015
  • Classification pursuant to EN 13501-3 up to EIS 120
  • Any air flow direction
  • CE certification according to EN 15650
  • Anticorrosive protection corresponding to EN 15650
  • Air losses according to EN 1751, Class 4
  • Nominal sizes from DN125 to DN630
  • Declaration of performance according to the Construction Products Regulation
  • CCertificate of Conformity issued by the producer


The casing is made of 1.3 mm metal sheet, painted in electrostatic field in order to provide the best possible corrosion resistance.
Inside the casing there is a gasket that expands at high temperature, ensuring the damper tightness to the occurrence of fire.
On the outside there is a Teflon and glass fiber foil plus two Intumex (fire-expandable material) strips that provide an additional tightening between the support and the damper, with a view to avoiding flame propagation around the fire damper.
A silicone rubber gasket is applied outward for sealing off the connection to the ventilation duct.
The fire damper blade is made of two 20mm plates of MGO magnesium oxide, an ecological construction material, the magnesium oxide plate being hard and lasting thanks to the very strong bonds among magnesium and oxygen atoms that form magnesium oxide crystals (chemical formula MgO).
Between the plates of the blade it is inserted a silicone rubber gasket to provide sealing at usual operating temperatures.
The actuator mechanism is made of 3 mm steel cut on laser for a movement precision as higher as possible. It is coupled to the actuator mechanism by means of a shaft with a bushing system.
The FD-EI120S circular fire dampers are equipped with a Belimo actuator mounted on the damper blocking shaft. During the actuator power supply, the shaft is rotated, bringing the flap to an open position (operating position) and, at the same time, straining the return spring.

The FD-EI120S circular fire dampers with Belimo actuators close as a result of the power supply interruption, having the effect of driving the return spring located in the actuator.

The triggering and control mechanism is as follows: Belimo type axial actuator of the series of products intended for fire-resistant dampers.

Upon request, it can also be made a fuse version driven by a spring. In this case, the Belimo type actuator is replaced by a spring that ensures the flap closure and the open position is maintained by a fuse element produced by Belimo. This fuse opens at a 72o temperature and the flap closes.

This system provides the same fire protection but it can not be ordered via the BMS and requires the maintenance team intervention for the periodic inspections.

Circular Fire Dampers FD-EI120S





Carcasa tabla 1.25mm pana la 1.5 mm functie de dimensiune, vopsita in camp electrostatic


Benzi exterioare autoadezive intumex 15×2 mm


Usa formata din 2 placi 20mm MGO


Placute montaj usa, tabla 1.5mm, vopsit electrostatic


Suport motor, tabla 1.5 mm, vopsit electrostatic


Carcasa ax OL




Bucsi bronz ax


Parghie mica actionare OL 3 mm


Pereche parghie mare actionare OL 2mm


Mecanism actionare ( motor tip Belimo, resort )


Senzor termic


Garnitura siliconica etansare la rece


Banda interioara autoadeziva intumex 60×2 mm, sigilare la cad


Banda autoadeziva protectie exterioara


Suruburi M5 fixare usa


Axe si saibe autoblocante montare mecanism


Ax usa OL


Bucsa incastrata pentru axul usii

Circular Fire Dampers FD-EI120S

Image during fire testing

Technical Specifications

The fire dampers produced within our company have European certification, with CE Marking

The tests have been achieved in compliance with EN 1366-2: 2015.

Classification according to EN 13501-3 up to EIS 120

CE certificate pursuant to EN 15650

Air losses in accordance with EN 1751, Class 4

Circular Fire Dampers FD-EI120S

Example with fuse and trip start/end contacts: FD-EI120S- F72°-2C- Ø 300
Example of 24V motorization with thermal sensor: FD-EI120S -BFN24T-Ø300

– The nominal sizes for circular fire dampers range from DN125 up to DN630
– Length of the casing – between 300mm and 400 mm
– Airflow – up to 13460 m3/h at 12m/s
– Triggering temperature – 72° in mod normal, or 95° for the hot air
– Air losses through the casing class C in accordance with EN 1751
– Air losses with closed blade class 4, according to EN 1751
– Resistance to corrosion in compliance with EN 15650
– The degree of permeability is pursuant to IPX 4
– As regards the risk of electric shock, the products belong to the
following categories of electrical appliances:
  • 3rd class (low voltage) for dampers with 24 V power supply
  • 2nd class (full insulation) for dampers with 230 V power supply from an actuator

The dampers are designed for operation in spaces with non- aggressive environment, the air temperature ranging from -20°C to +60°C and relative humidity up to 80%.
The fire dampers cannot be mounted in enclosures or air drains with danger of explosion, air pipes for flammable or explosive mixtures.

Delivery and Accompanying Documents

The fire dampers delivery will be carried out only accompanied by the following documents:

– Document of origin
– Declaration concerning quality and conformity
– Directions for installation
– Maintenance and operating directions

On the damper it is attached the product label specifying the product identification data (sizes, batch series, manufacturing date) as well as the CE marking number.

The beneficiary has to check the compliance of these data with those of the ordered product.

Storage and Transport


For transport the fire dampers will be individually packed or grouped on a wooden pallet and wrapped. In the truck it will be ensured a protection against shocks. It is not advisable to transport in uncovered cars if the weather is unfavorable.

It should be taken into account that the temperature inside the car must not exceed 65 degrees C.
During transport the fire damper flaps will be in the closed position.

Check the fire dampers at the goods arrival to see if there is any damage. In case of finding any damage or lack, please contact immediately the shipping company and the supplier.


For storage there are not required special conditions, but it is recommended a dry place and away from direct sunlight. The storage temperature cannot degrade the fire dampers, but it should be taken into account not to exceed 65 degrees C. At 72 degrees C the thermal sensor is triggered, if this happens, it will be necessary to replace it.

Installation Instructions

Before starting the installation proper, please read these directions for installation. The installation should be carried out by qualified personnel, such as electricians, HVAC technicians, or persons with technical knowledge.

The fire dampers are mounted on ventilation ducts, at the wall bushings through the walls defining the fire compartments.

The opening fill will be carried with basaltic mineral wool (having a density between 140 -180 kg/m3 – e.g. 50 mm ROCKWOOL mineral wool) and the outer sides will be finished with common finishing items (drywall, plaster putty – e.g. Rigips).

According to the size of the dampers there will be made holes for the wall bushings; they can be round or square-shaped, having the size greater than D by 100 mm.

Circular Fire Dampers FD-EI120S

Damper Name


Wall Opening




FD-EI120S -BFL24T-DN125




Ø225 sau 225×225

FD-EI120S -BFL24T-DN160




Ø260 sau 260×260

FD-EI120S -BFL24T-DN180




Ø280 sau 280×280

FD-EI120S -BFL24T-DN200




Ø300 sau 300×300

FD-EI120S -BFL24T-DN250




Ø350 sau 350×350

FD-EI120S -BFL24T-DN315




Ø415 sau 415×415

FD-EI120S -BFL24T-DN355




Ø455 sau 455×455

FD-EI120S -BFl24T-DN400




Ø500 sau 500×500

FD-EI120S -BFN24T-DN450




Ø550 sau 550×550

FD-EI120S -BFN24T-DN500




Ø600 sau 600×600

FD-EI120S -BFN24T-DN560




Ø660 sau 660×660

FD-EI120S -BFN24T-DN630




Ø730 sau 730×730

Before installation, each fire damper is inspected visually, checking if the blade opens friction-free.

The fire damper is mounted with the door closed, and there will be added 2 stiffening elements in order to prevent deformation of the damper during mounting.
Especially in large sizes it is possible to occur the blade blocking in case the fire damper is inadequately mounted.

Or it can be used the mounting kit that we deliver separately, consisting of 4 pieces of RF drywall of 12.5 mm thickness in which there are cut semicircles of a diameter corresponding to the fire damper, mineral wool required, high temperature resistant silicone sealant.

Below are shown the steps of the installation with mounting kit.

Circular Fire Dampers FD-EI120S
Circular Fire Dampers FD-EI120S