Aluminium coils, sheets and foils undergo annealing to relieve stress, restore ductility and achieve target temper. The process is sensitive to atmosphere control, heating profile and surface contact — the right furnace design directly determines product quality.
🌫️ Why Controlled Atmosphere?
Without protective atmosphere, the aluminium surface oxidises during annealing, causing dull appearance, lubricant residue burn-in and downstream rolling defects. With H₂ or N₂ atmosphere, the surface remains bright and lubricant burns off cleanly. For foil and high-grade sheet products this is mandatory; for general-purpose annealing it is a quality differentiator.
Furnace Types
Batch / Continuous / Bell-type
Temperature Range
250 – 600 °C
Atmosphere
H₂ / N₂ / H₂-N₂ mix / air
Coil Diameter
Project-specific (up to ⌀ 2200 mm)
Heating
Natural gas / electric / dual
Temperature Uniformity
±5 °C
Control
PLC / SCADA — recipe + recording
Alloy Compatibility
1xxx · 3xxx · 5xxx · 8xxx
Capacity
Project-specific (10–80+ ton/charge)
Batch Sheet Annealing: Stacked sheet packages, racking systems with lifting equipment. Suitable for medium volumes and varied alloy/temper recipes." data-ru="Batch Sheet Annealing: Stacked sheet packages, racking systems with lifting equipment. Suitable for medium volumes and varied alloy/temper recipes.
Atmosphere Control System: H₂/N₂ generators, dew point monitoring, oxygen analysis, leak detection — bright surface guarantee." data-ru="Atmosphere Control System: H₂/N₂ generators, dew point monitoring, oxygen analysis, leak detection — bright surface guarantee.
Energy Recovery Options: Recuperative burners, exhaust heat recovery, thermal insulation upgrades — operational cost reduction." data-ru="Energy Recovery Options: Recuperative burners, exhaust heat recovery, thermal insulation upgrades — operational cost reduction.
