KÖRNER galvanizing furnace
The galvanizing furnace is the heart of any galvanizing line. Its design has decisive influence on the quality of the zinc coating and on the costs of production. Galvanizing furnaces from Zink KÖRNER incorporate a wide gamut of design features that ensure highest efficiency of the batch galvanizing process: By implementing modulating, infinitely adjustable flat flame burners, a wall construction with less heat transfer and a novel reflecting refractory coating, Zink KÖRNER significantly increases the energy efficiency of batch galvanizing.
Zink KÖRNER is the only supplier of furnaces that use burners specifically developed for batch galvanizing. Thanks to these burners, galvanizing furnaces reach efficiencies of up to 75 per- cent – which is 5 to 10 percent better than conventional plants. Unlike the burners commonly used in the past, the gas-fired flat flame burners of the FL 20/50 type operate in a modulating mode. They are infinitely adjustable within a range of 1:10. They guarantee the same smooth and mild heating as previously only achievable by electrically heated furnaces. The control system permanently adjusts the power to the throughput rate of the furnace and avoids abrupt temperature changes, which may cause excessive stresses in the galvanizing tank structure.
Energy consumption is minimized as a result of various specific design features. Diffusor plates mounted on the burners direct the gas flow along the inner furnace wall. This produces a combination of radiant and convective heat, which has the positive effect that a high input of heat into the galvanizing tank is achieved at relatively low furnace temperatures. The multi-layer, up to 300-mm-thick insulation reduces heat loss. Additionally, the innovative ceramic coating applied to the fibrous insulation reflects the radiant heat towards the interior of the furnace.
Compared with plants using impulse burners, the flat flame burners employed by Zink KÖRNER use much less energy. For example, a furnace with a throughput of 15 t/h operated in two shifts for 4,000 hours per year consumes about 500,000 kWh less. At a price of 5 cents per kWh, this results in cost savings of 25,000 euros per year.
A clean metallic surface is one of the basic necessities of the galvanizing process - the parts to be galvanized have therefore to be pre-treated. KÖRNER also supplies these pre-treatment plants. They consist of degreasing, pickling, rinsing and fluxing agent baths.
On request, the pre-treatment facilities can be provided with encapsulation, to collect and filter the acid vapours.
The steel pieces are then dried in the drying furnace from Zink KÖRNER and immediately pre-heated for the galvanizing process.
To increase work safety, Zink KÖRNER makes hot dip galvanizing furnaces with housings, which keep the zinc bath from unauthorised access and effectively vacuum and filter the dust created by the galvanizing.