Curing powder coatings is a thermally precise process: heating, gelling, flow-out and chemical cross-linking must occur within defined temperature-time windows. Gas-fired infrared metal fibre burners deliver the required radiation intensity quickly, uniformly and cost-efficiently – outperforming both convection ovens and electric IR emitters in overall economics.

The Curing Process: Gelling, Flow-Out, Cross-Linking

When curing powder coatings, the workpiece passes through three physicochemical stages, all of which must occur within narrow temperature limits:

Melting (Gelling): The electrostatically applied powder melts from approx. 80 °C. The particles coalesce into a continuous film – this step is time-critical for final coating quality.
Flow-Out & Levelling: The molten film smooths under gravity and surface tension. Too slow a heating rate causes orange peel; too rapid heating leads to pinholes and blistering.
Curing (Cross-Linking): At 160–220 °C – depending on powder type (epoxy, polyester, polyurethane, hybrid) – the coating chemically cross-links to full hardness within 10–20 minutes.

Infrared radiation in the mid-range (2–5 µm) is absorbed particularly efficiently by organic powder coatings. The radiant energy penetrates directly into the coating film – without the detour via ambient air – delivering the required heat exactly where it is needed.

Metal Fibre Burners in Powder Coating

Metal fibre burners (MFB) from I-TPT are gas-fired infrared emitters with a porous fibre matrix made from high-temperature-resistant metal alloys. Combustion occurs at the surface of the fibre fleece – the glowing matrix emits intensive IR radiation with an emissivity of ε ≈ 0.9 and a radiation temperature typically of 850–950 °C.

The surface heat output is exceptionally homogeneous: temperature differences across the burner face are typically less than ±15 K – a decisive advantage over individual emitters. The power density of 100–500 kW/m² is comparable to electric short-wave emitters, yet operating costs with natural gas or biogas are significantly lower.

Gas Infrared vs. Electric IR Emitter vs. Convection Oven

Parameter	Metal Fibre Burner (Gas-IR)	Electric IR Emitter	Convection Oven
Heating rate	very fast (< 60 s)	fast (30–90 s)	slow (3–10 min)
Power density	100–500 kW/m²	50–200 kW/m²	10–30 kW/m²
Heat uniformity	very high (±15 K)	medium	high (convection)
Energy costs	low (gas/H₂)	high (electricity)	medium
H₂ blending	up to 15%	n/a	partially possible
Line length reduction	–60 to –70%	–50 to –70%	reference
Capital cost	medium	low–medium	medium–high

Indicative values; depending on part geometry, powder type and line speed.

Typical Applications in Powder Coating

Automotive & suppliers – rims, cross-members, engine components, door handles
White goods – refrigerator and washing machine housings, oven panels
Office furniture & profiles – aluminium systems, steel frames and visible surfaces
Coil coating lines – continuous coating of steel and aluminium strip
Agricultural machinery – primer and topcoat on large attachments
Coating contractors – continuous lines for varying parts and batch sizes 1 to large series
Architecture & facades – coating of aluminium extrusion profiles

Why Metal Fibre Burners from I-TPT?

I-TPT develops and manufactures customer-specific IR burner systems for powder coating lines – from individual components to complete ready-to-run plants:

Design matched to your part geometry and throughput (thermodynamic simulation & CFD)
Modular burner panels for inline, portal-type and chamber drying systems
Complete ignition, control and safety systems from a single source
Gas-fired with natural gas, biogas or H₂/CH₄ mixtures (up to 15% H₂)
Factory acceptance testing and on-site commissioning
Ongoing support, optimisation and adaptation during operation

Planning a New Line or Retrofitting?

Planning a new powder coating line or looking to retrofit an existing conveyor oven with gas-fired IR emitters? I-TPT advises on design, economic viability and funding opportunities.