Both series are available in 19 sizes, up to 2,450 mm impeller diameter, and can be paired with special executions independently of blade geometry: stainless steel AISI, ATEX execution (on request), gastight execution, insulated execution. The only structural difference between the two ranges is inlet configuration: Ch is single-inlet, ChT is double-inlet.
For duty that is not entirely clean, the ChT range also offers the ChBT impeller: same welded aerodynamic-profile construction, efficiency up to 86%, built for fine, dry, non-abrasive powders or higher moisture rates. It sits between the flat backward-inclined ChB impeller and the full airfoil ChAT for airstreams that fall short of "clean and dry."
Airflow, Pressure and Efficiency: What Changes
Blade profile does change how much airflow a centrifugal fan can move: alongside impeller diameter and rotational speed, blade type is one of the factors that sets the flow a Ch or ChT fan delivers at a given duty point. ChT is built to move substantially more air than Ch - up to 750,000 m³/h against 460,000 m³/h - a gap driven by its double-inlet design rather than by blade geometry alone.
What the airfoil blade also changes is how efficiently that airflow is delivered, and at what noise and structural cost. This is the distinction worth keeping in mind when comparing an airfoil centrifugal fan against a standard backward curved unit on paper: matching m³/h and Pa figures is not enough, the impeller geometry decides what it costs to sustain them over the life of the plant.
Where Airfoil Impellers Make Sense
Airfoil-blade centrifugal fans earn their place when two conditions overlap: the air is genuinely clean and dry, and static pressure or noise level actually matter to the project. The efficiency gain compounds with operating hours, but hours on their own don't decide the geometry.
Typical duty:
- Air conditioning circuits and filtered ventilation;
- Clean industrial drying and product cooling on dry lines;
- Spray booths and enclosures with tight noise constraints;
- Steel or metal production plants;
- Any high-hour installation where a few efficiency points show up on the energy bill over a year.
Where dust, fibres or condensation can reach the blade, a flat backward inclined or backward curved impeller stays the more resilient choice. CBI's technical team can confirm which geometry fits the actual duty before specification.
