Welding Machine & Inverter Cooling Fan

An inverter welder is a hostile place for a fan: IGBT modules bolted to a dense fin stack, grinding dust and metal particles pulled in from the workshop floor, and internal air that passes 60–70 °C on a high duty cycle. The fan has to hold its airflow against that restriction for years, in a machine that is dragged around a site. We build 92–280 mm AC 110/220/380 V and 24 V DC fans for this duty, with metal guards and filters to match.

Part of: cooling fan applications · also relevant to industrial enclosures.

What a welder fan has to cope with

A dense fin stack. IGBT and diode modules sit on a heatsink with narrow fin spacing, which is a real pressure drop. Free-air airflow figures are meaningless here; the fan needs pressure to push air through the gaps.
Dust and metal particles. Grinding dust is conductive and abrasive. It shorts boards and it wears bearings, so a filter or a coarse mesh plus a fan that tolerates a dusty impeller is part of the design.
High duty cycle, high temperature. At 60% duty the internal air stays hot for hours. Plastic impellers soften, lubricant migrates, and a fan that was fine on a bench fails in a fabrication shop.
Mains-powered simplicity. Most 200–400 A machines use a 220 V AC fan wired straight to the auxiliary supply, because there is no convenient DC rail and no controller to drive PWM.

Fan sizes and voltages for welding equipment

Frame	Typical machine	Voltage	Models
92–120 mm	compact inverter, 160–200 A	220 V AC / 24 V DC	AC 9238, AC 12038
120 mm DC	battery welder, engine-driven unit	24 V DC	DC 12038
172 mm	315–400 A inverter	220 V AC / 24 V DC	AC 17251, DC 17251
225–280 mm	industrial welder, multi-process power source	220 / 380 V AC	AC 22580, AC 28080
Accessories	finger guard and filter	—	120 mm guard, 120 mm filter

Where welder cooling goes wrong

Plastic impeller at 70 °C. The blades creep and start to rub the venturi, airflow drops and the machine derates on thermal overload in the middle of a job. Metal or high-temperature PBT impellers are specified for this reason.
No guard. A finger guard is a safety item first, but it also stops welding wire, tools and large particles from entering the blade path.
Wrong polarity on a DC fan. A 24 V fan wired backwards does not start, and the machine’s thermal protection is the only thing that notices. Specify the connector so the harness cannot be reversed.

How to specify a welder fan

Fin stack geometry and the airflow the module datasheet requires.
Duty cycle and the internal air temperature at the fan.
Supply available: 110 V, 220 V or 380 V AC, or a 24 V DC rail.
Dust level on site and whether a filter is part of the service schedule.
Sound level target, since welders are used in confined workshops.

Questions from welding equipment manufacturers

AC or DC fan for a 200 A inverter welder?

AC 220 V is the common choice because the machine already has a mains-derived auxiliary supply and no controller to drive a DC fan. DC 24 V is used on battery and engine-driven welders, and where the fan has to keep running from a control rail during a mains dip.

Can the fan handle grinding dust?

The fan can tolerate a dusty impeller if the bearing is protected and the blades are cleaned at service. What it cannot tolerate is a blocked filter, so specify a filter with enough area and make it part of the service schedule, or fit a coarse mesh where the site is very dirty.

Do you supply a metal impeller version?

We can supply high-temperature impeller materials for welder duty. Send the internal air temperature and the duty cycle and we will confirm which frame and material combination fits.

Send the fin stack, the duty cycle and the supply voltage, and we will propose a frame with the pressure margin for a hot machine. Request a quotation.