How is a kiln-exhaust fan different from a plain ID fan?
It is an ID fan defined by the kiln or furnace context. Both sit downstream and pull hot gas to the stack, but kiln exhaust adds three things at once: the gas runs hotter (often 200-450 °C, up to 600 °C at the ceiling), it carries the mineral dust of the process itself (clinker, ceramic body, scale, grit) rather than clean fly ash, and on some kilns it turns alkali-laden or drops below the acid dew point. So we build it with a rugged radial wheel, replaceable wear protection sized to the mineral dust, and metallurgy chosen for the gas chemistry, not a generic ID rating.
What is the maximum gas temperature you handle on kiln exhaust?
Continuous duty up to 600 °C across the envelope, with most kiln and furnace exhaust running 200 to 450 °C. Above about 150 to 350 °C we fit a shaft cooling disc to keep heat off the bearings, keep the bearings outside the airstream, and add expansion joints for the thermal growth (a 1 m shaft grows about 7 mm from cold to 600 °C). Refractory lining is attested to 600 °C for the hottest kiln duty. The fan is built for your stated gas temperature and excursion case, not a generic rating.
How do you protect the wheel from clinker and mineral dust?
Kiln dust is the hardest and sharpest in any fan duty, so we protect three ways, specified to your loading (a heavy load on raw exhaust). A rugged radial or radial-tip wheel that sheds dust and resists erosion; chrome-carbide hard-facing on the blade leading edges and high-wear zones; and bolted-in, replaceable wear plates and liners at the scroll throat and inlet with inspection and cleanout doors, so worn parts change out in place. The wear scope is replaceable, not welded in.
Our kiln gas is alkali-laden and drops below the acid dew point. What do you do?
We size the metallurgy and the dew-point margin to your gas analysis. On alkali-laden gas we choose blade geometry that does not let alkali key onto the wheel and specify corrosion-resistant material where it condenses. Below the acid dew point (typically 120 to 150 °C) we keep the casing wall above dew point with insulation and heat tracing and select Corten or 316L on the wetted surfaces, stepping to higher alloys on request. The right answer depends on your alkali content, SO₂/SO₃ and moisture, so we engineer it to your gas, not a default.
Can you build a replacement to match our existing kiln fan's duty and footprint?
Yes. We reverse-engineer to the existing duty point (flow, static pressure, gas temperature, density and dust load), bearing centres, inlet/outlet orientation and foundation bolt pattern so the unit drops onto the existing base and ducting. Made to your installation, not a nearest-catalogue substitute. Send the old GA, the nameplate and a curve if you have one, and we match it.
What draft-control and accessory scope comes with the fan?
Scope is specified per duty. Draft control by VFD (our default for variable-draft service, since speed control avoids the throttling loss of a damper at part-load), inlet guide vanes, or an isolation / shut-off damper. We supply matched flexible connections / expansion joints, impeller wear protection, bolted-in wear plates and liners, a heat slinger / cooling disc where temperature requires, water-cooled bearings above 200 °C, special material of construction for aggressive gas, and inspection / cleanout doors. Tell us the battery limit and we quote the accessories inside it.
How fast can you ship a shutdown replacement for a kiln fan?
Shutdown replacements ship within 6 weeks of a clean PO. A standard engineered kiln-exhaust fan runs roughly 12 to 18 weeks order-to-dispatch (offer 5 to 7 working days, GA approval 3 to 4 weeks, manufacture, balance and paint 8 to 12 weeks, cold performance test and FAT 1 to 2 weeks). A refractory-lined 600 °C build runs longer. For an emergency we prioritise the wheel and bearings and confirm a dated commitment against your shutdown window, a real date, not a placeholder.
How do you test the fan, and what about CE, ATEX and quality certification?
Every fan is performance-tested in-house to the AMCA 210 / ISO 5801 method on our 200 HP VFD test rig. Because the rig runs cold air, hot kiln-gas operation is extrapolated by fan-law correction for density, and the fan is dynamically balanced to ISO 21940 G6.3 as standard (G2.5 / G1.0 on application). To be precise: that in-house testing is to the AMCA 210 method, not AMCA-certified. CE is self-declared per 2006/42/EC and 2014/35/EU, and ATEX Zone 2/22 is self-declared per 2014/34/EU (Category 3) where the area classification calls for it, though hot kiln gas is often above the dust auto-ignition temperature and not ATEX-classified. Those are self-declarations of conformity, not third-party certifications; our only third-party certification is ISO 9001:2015.
