Continuous Galvanizing Line Annealing Furnaces are used to heat, soak, and cool cold-rolled steel strip before it enters the zinc bath. Depending on the production line, these furnaces may have vertical or horizontal configurations, incorporating direct-fired heating, non-oxidizing heating, radiant tube soaking, and gas jet cooling.

Each furnace section operates under different thermal loads, furnace atmospheres, and gas-flow conditions, requiring a zoned approach to insulation design.

CCEWOOL provides ceramic fiber blanket insulation in different temperature grades, thicknesses, and densities to meet the requirements of individual furnace sections. By combining Ceramic Fiber Blanket with Ceramic Fiber Modules and other insulation materials, we support zone-specific lining configurations.

The key is to determine where the blanket will be installed before selecting the appropriate insulation and protective structure.

High-Heat-Load Heating Zones: Protected Backup Insulation Reduces Heat Transfer to the Furnace Shell

Areas around burners, furnace roofs, and high-temperature gas passages in direct-fired heating sections are exposed to localized high temperatures, flames, and gas-flow erosion.

Where lightweight insulating fire bricks or refractory castables are used as the hot-face working lining, CCEWOOL ceramic fiber blanket can be installed behind these materials as continuous backup insulation. Its flexible roll structure helps reduce heat transfer toward the furnace shell while accommodating local variations in lining geometry.

In areas with lower gas-flow intensity and suitable conditions for fiber hot-face linings, CCEWOOL Ceramic Fiber Modules can be combined with Ceramic Fiber Blanket backup insulation. The modules provide hot-face insulation, while the blanket forms a continuous insulation layer behind them. Anchoring arrangements, lining thickness, and joint details are selected according to the furnace-shell structure.

These configurations allow each material to perform its intended function, with the specific combination determined by the operating conditions of each location.

Ceramic Fiber Blanket is easy to cut, install, and adapt to local contours, and the material itself has low heat storage. When installed behind a heavy refractory working lining, its primary contribution is to improve backup insulation and reduce heat transfer.

Any assessment of total lining heat storage must also consider the refractory working layer and the complete lining design. Distinguishing between these functions helps clarify the value of furnace insulation blanket in multilayer furnace linings.

Radiant Tube Soaking Zones: Matching Fiber Insulation to Furnace Atmosphere and Interface Temperature

Radiant tubes indirectly transfer heat to the steel strip. For some steel grades, annealing temperatures can reach approximately 900°C, depending on the processing conditions.

This refers to the strip-processing temperature, not necessarily the temperature experienced by the fiber backup insulation.

The selection of CCEWOOL ceramic fiber blanket insulation should therefore be based on the long-term interface temperature at its installed position, together with the nitrogen-hydrogen atmosphere composition, dew point, and local gas-flow conditions.

In a tower-type furnace application documented by CCEWOOL, the soaking zone incorporates a fiber insulation layer between heat-resistant steel plates. This arrangement reduces the direct exposure of the fiber material to furnace gas flow.

In other lining designs where Ceramic Fiber Modules are suitable for hot-face insulation, Ceramic Fiber Blanket can serve as a continuous backup layer behind the modules. These configurations demonstrate how insulation materials can be arranged differently according to furnace design.

Internal protective plates provide surface protection, while lining joints and furnace gas-tightness requirements must be addressed through appropriate structural and sealing design.

By distinguishing these functions, customers can evaluate protective layers, fiber temperature grades, and installation requirements separately.

CCEWOOL supports these requirements with Ceramic Fiber Blanket options in different temperature grades, thicknesses, and dimensions according to the specific installation position.

Rapid Cooling Zones: Balancing Continuous Insulation and Gas-Flow Protection

After soaking, the steel strip must be cooled to the required temperature before entering the zinc bath. Some continuous galvanizing lines use high-velocity circulating gas or gas jet cooling systems.

Although the overall thermal load in these sections is generally lower, direct exposure of insulation materials to strong gas flow remains an important factor in lining design.

For furnace walls and roofs equipped with suitable internal protective plates or other protective structures, CCEWOOL ceramic fiber blanket can be installed in flat-laid or multilayer configurations with staggered joints and appropriate fixing methods to provide continuous insulation.

The selection of thickness, density, and cut-to-size dimensions should satisfy thermal design requirements while accommodating installation around corners and equipment interfaces.

Where the fiber insulation layer is directly exposed to strong gas flow, erosion resistance, surface protection, and fixing reliability must be evaluated accordingly.

Transition areas between furnace sections also require consideration of temperature differences, structural gaps, and furnace atmosphere sealing.

Depending on the installation location, CCEWOOL can supply Ceramic Fiber Blanket together with suitable Ceramic Fiber Modules, Ceramic Fiber Boards, Calcium Silicate Boards, and refractory working-lining materials.

From protected backup insulation in heating zones to interlayer insulation in soaking zones and continuous insulation in cooling zones, CCEWOOL matches material selection to the operating conditions of each furnace section.

By considering temperature, furnace atmosphere, gas flow, and lining structure, CCEWOOL? helps customers identify the function of each insulation layer and establish clear technical requirements for product selection, supply, and installation.