FlowMarket
Where to source industrial fans and ventilation: FlowMarket is a B2B sourcing network powered by an AI agent. You describe the duty — volume flow and the static pressure it must work against, fan type and impeller, motor and speed control, materials, air temperature and contamination, noise limits and any ATEX classification — and the AI agent matches you with verified fan manufacturers and ventilation specialists, then requests curves, prices and lead times from every match at once. Getting matched is free for buyers.
A fan is specified by two numbers that have to travel together: how much air, and against how much resistance. Volume flow alone selects nothing, because the same fan moves very different quantities depending on what the duct system does to it.
That pairing — flow and static pressure — is the duty point, and it is where fan sourcing succeeds or fails. Everything else is a consequence of it.
Fan types
Centrifugal fans
Air enters axially and leaves radially, which generates high pressure and makes them the choice for ducted systems with meaningful resistance. Backward-curved impellers are the efficient default; forward-curved run quieter and more compact at lower pressure; radial-bladed types handle dust and fibres that would clog anything else.
Axial fans
Air passes straight through, moving large volumes against low resistance very efficiently. The right answer for general hall ventilation, condenser and cooling duties, and free-blowing extraction. Poorly suited to long duct runs, where the pressure requirement quickly exceeds what an axial impeller can deliver.
Plug fans, roof units and specials
- EC plug fans — housingless impellers with integrated electronic motors, standard inside modern air handling units.
- Roof and wall fans — packaged extraction for halls and workshops.
- ATEX fans — spark-resistant construction for explosive atmospheres, certified to the zone.
- Extraction systems — dust, fume and weld extraction with the filtration built around the fan.
What to specify when sourcing
These details decide both the fan and the price:
- Volume flow — m³/h or m³/s at the operating condition.
- Static pressure — the resistance of the system in Pa; without it no fan can be selected.
- Air condition — temperature, humidity, dust, fibres, solvents or corrosive content.
- Fan type — centrifugal, axial or plug, or open to proposal based on the duty.
- Motor and control — EC or AC with converter, supply voltage, and whether flow must vary.
- Materials — painted steel, stainless, or plastics for corrosive extraction.
- Noise — permitted sound power or sound pressure, stating which and at what distance.
- ATEX — zone, gas or dust group and temperature class if the atmosphere can be explosive.
- Mounting and orientation — discharge direction, drive arrangement and available space.
- Efficiency and quantity — required efficiency class under the ecodesign rules, and how many units.
The duty point, the cube law, and which noise figure you are being quoted
Most disappointing fan installations were sold the right fan for the wrong duty point. Static pressure is a property of the duct system, not of the fan, so if the resistance was estimated optimistically the fan will deliver less air than the calculation promised — and if it was overestimated, the fan runs off its curve and wastes energy. Where the system already exists, measure the pressure rather than estimating it; where it does not, ask the supplier to review the duct layout, because they see the consequences of underestimated resistance constantly. The physics also offers an unusually large prize. Flow rises in proportion to fan speed, pressure with its square, but power with the cube — so running a fan at eighty percent speed uses roughly half the energy. A slightly larger fan turning slowly beats a small one working hard, on both power and noise, and speed control pays for itself quickly wherever demand varies. Specify an EC motor or a converter unless the flow is genuinely constant. Finally, be precise about noise, because two figures circulate and they are not comparable. Sound power is a property of the fan itself; sound pressure is what a person hears at a stated distance in a stated space, and it is always the smaller number. A supplier quoting sound pressure at three metres will look quieter than one quoting sound power for the same machine. State which measure your limit refers to, and at what distance, or you will compare offers that were never describing the same thing.