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CBJET series

High-performance jet fans engineered for tunnel ventilation and certified for smoke extraction up to 400°C for 2 hours

The CBJET series is specifically designed for installation inside tunnels and galleries.

Jet fans are a key component in tunnel ventilation systems, where they are used to generate and control airflow during both normal operation and emergency conditions. Different tunnel configurations may require different ventilation strategies depending on tunnel geometry, length, traffic conditions and safety requirements.

Learn more about the different tunnel ventilation systems and how longitudinal, semi-transversal and transversal ventilation work.

It is built to the highest quality standards to ensure reliable operation over the years and to be suitable for smoke extraction in case of fire. The fans are tested and certified to the strictest international fire safety standards EN 12101-3 in order to operate up to 400°C/2h.

The performance of the fans are certified, ensured by aeraulic tests in compliance with International Regulations (AMCA and ISO) in order to meet or exceed all the technical requirements of the project specifications.

Technical specifications:

Impeller diameter: up to 1.600 mm
Thrust: from 270 N to 3.000 N
Flow rates: 250.000 m³/h
Configuration: direct driven

Accessories

Complementary components engineered for optimal integration and long-term efficiency

Spring suspension group

Consisting of no. 4 anti-vibration spring shock absorbers made of UNI 7900 harmonic steel fitted with containment disks and steel spring coated with a vulcanized anti-oil elastomeric mix.

The installation of a suspension group involves the supply of fastening brackets of the spiral which differ from standard supply and provided with stiff fastening to the tunnel ceiling.

Brackets

Angled or flat plates for horizontal vault mounting of the fan, it can be customized in function of the vault design.

It is usually made of the same material applied for the fans.

Vibration detection system

The vibration transmitter can be connected to the power supply control board (installation excluded) for threshold control, complete with analogue output 4-20 mA.

Horizontal position detector sensor

It allows to detect changes in the horizontality of the installed jet fan, and allows to anticipate falling of the fan from vault.

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Energy efficiency

To address the demand for energy cost savings, this series incorporates integrative aerodynamic components developed by our research and development team. These elements are specifically engineered to markedly improve fan performance while optimizing electricity consumption.

Aerodynamically profiled nozzles

The objective is to greatly minimize pressure losses at both the inlet and outlet.

Ogives

The setup includes the installation of two aerodynamic ogives: one on the impeller and the other at the rear of the motor. These elements are intended to minimize turbulence around crucial areas, streamline aerodynamic flows, and reduce the necessary workload.

Grids

With their square mesh geometry and the use of specially designed elements, they have a dual effect:

Increased useful fluid passage area, resulting in reduced pressure loss;
Straightening function: the thin layers of fluid are straightened and uniformed before processing by the impeller.

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Maintenance program

Regular maintenance is essential to ensure the reliability, performance and safety of tunnel ventilation systems throughout their operating life.

For CBJET jet fans, maintenance activities can be planned according to different inspection intervals:

Annual maintenance: visual inspections, checks of the impeller, casing, suspension system and accessories, vibration monitoring and verification of the main electrical and mechanical components.
Five-year maintenance: more extensive inspections of the fan and its components, including detailed checks of mechanical parts, electrical connections, supports, grids and silencers, with replacement or servicing where required.
Ten-year maintenance: comprehensive assessment of the fan condition, including in-depth inspection of the main components and evaluation of any overhaul, refurbishment or replacement activities required to restore full reliability and performance.

CBI Group provides scheduled, predictive and extraordinary maintenance services for tunnel and metro ventilation fans, supporting customers throughout the entire lifecycle of the equipment.

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