Ceramic Fiber Blanket

Ceramic fiber blanket is the most widely used and versatile form of refractory ceramic fiber insulation, supplied as a flexible, needled or stitched mat that can be cut, wrapped, layered, and shaped to fit virtually any high-temperature insulation application. Manufactured from spun or blown alumina-silicate fibers — or higher-purity alumina and zirconia-modified formulations for higher-temperature grades — ceramic fiber blanket combines low thermal conductivity, low thermal mass, and exceptional flexibility, making it the standard insulation choice across furnace lining, industrial pipe and duct wrapping, kiln construction, expansion joint sealing, and countless other high-temperature applications where rigid insulation products can’t easily conform to the geometry involved.

We supply ceramic fiber blanket across the full range of standard classification temperatures — 1260°C, 1400°C, and 1600°C — in multiple density and thickness options, available in standard roll sizes or custom-cut dimensions to match your specific project requirements. This page covers the material’s properties, manufacturing process, available grades, installation methods, application industries, technical specifications, and selection guidance to help you choose the right ceramic fiber blanket for your project.

What Is Ceramic Fiber Blanket?

Ceramic fiber blanket is produced by spinning or blowing molten refractory raw materials — primarily alumina (Al2O3) and silica (SiO2), often with zirconia (ZrO2) added for higher-temperature grades — into fine, flexible fibers. These fibers are then collected, layered, and mechanically needled (or, in some product variants, stitched with high-temperature-resistant thread) to bind the fiber mat into a cohesive, flexible blanket structure without the use of organic binders that would burn out and compromise structural integrity at operating temperature.

The needling process is what gives ceramic fiber blanket its characteristic combination of flexibility and structural cohesion — mechanical interlocking of the fibers through the needling process holds the blanket together and gives it enough tensile strength to be handled, cut, and installed without a chemical binder, while still allowing the material to bend, wrap, and conform to curved and irregular surfaces in a way that rigid board or vacuum-formed products cannot.

Key Physical Characteristics

Chemical inertness — resistant to most common industrial atmospheres and chemical exposures encountered in furnace, kiln, and process equipment insulation applicationsshift to a polycrystalline alumina fiber formulation for service above 1400°C. The molten mixture is spun or blown into fibers using a centrifugal or blowing.

Low density — typically ranging from 64 to 160 kg/m³ depending on grade and intended application, dramatically lighter than dense refractory brick or castable.

Low thermal conductivity — the air-trapping fibrous structure provides excellent insulating performance per unit thickness, with conductivity values that remain low even at elevated mean temperatures.

High flexibility — can be wrapped around pipes, elbows, curved furnace surfaces, and irregular equipment geometry without cracking or requiring extensive field fabrication.

Low thermal mass — minimal material mass means less energy is consumed heating the insulation itself, supporting faster heat-up and cool-down in cyclic applications.

Thermal shock resistance — the flexible fiber structure accommodates thermal expansion and contraction without the cracking and spalling failure modes common to rigid refractory materials under repeated or rapid temperature swings.

How Ceramic Fiber Blanket Is Manufactured

Understanding the manufacturing process helps explain why ceramic fiber blanket performs the way it does, and why quality can vary meaningfully between suppliers.

1. Raw Material Melting — Alumina and silica raw materials (with zirconia or other additives for specialty grades) are melted together at extremely high temperature in an electric or fuel-fired furnace.

2. Fiberization — The molten material stream is subjected to either a spinning process (where the melt contacts high-speed spinning wheels that fling the material into fine fibers) or a blowing process (where high-velocity air or steam jets draw the melt into fibers). Spun fiber and blown fiber have somewhat different fiber diameter characteristics and physical properties, with fiber production method being one of the variables that differentiates blanket products between manufacturers.

3. Fiber Collection — The newly formed fibers are collected on a moving conveyor or collection system, building up into a continuous fiber mat (often called “raw” or “as-formed” blanket at this stage) of relatively low, uncompressed density.

4. Needling — The collected fiber mat passes through a needling process, where barbed needles repeatedly punch through the mat, mechanically interlocking fibers from different layers and compressing the material to its target density. This needling process is what transforms loose fiber into a cohesive, handleable blanket product with defined tensile strength and structural integrity.

5. Cutting, Rolling, and Packaging — The finished blanket is cut to standard widths, rolled onto cores for shipment and handling, and packaged — typically in moisture-resistant packaging to protect the product during storage and transport prior to installation.

Quality factors that vary between manufacturers include raw material purity (affecting classification temperature and shrinkage performance), fiber diameter and length distribution (affecting both insulating performance and airborne fiber characteristics), needling density and consistency (affecting blanket tensile strength and long-term structural stability), and overall density uniformity across the roll (affecting consistent insulating performance across the full installed area).

Available Grades and Classification Temperatures

Ceramic fiber blanket is manufactured and sold according to standardized classification temperature grades, which indicate the maximum temperature at which the material can be used continuously without excessive shrinkage or structural degradation. Selecting the appropriate grade — with adequate margin above your actual application temperature — is one of the most important decisions in specifying ceramic fiber blanket.

1260°C Class (Standard Grade)

The most widely used and cost-effective grade, manufactured from standard alumina-silicate fiber composition. Suitable for the large majority of general industrial insulation applications — furnace backup insulation, pipe and duct wrapping, general kiln construction, and countless other applications operating up to approximately 1100-1150°C continuous service temperature.

1400°C Class

Manufactured with a higher alumina content than standard grade, this classification offers extended high-temperature performance for furnaces, kilns, and process equipment operating up to approximately 1250-1300°C continuously — commonly specified for hot-face applications in industrial furnaces, higher-temperature kiln zones, and process equipment where standard-grade fiber would be operating too close to its temperature limit for reliable long-term performance.

1600°C Class (High-Purity/Polycrystalline Grade)

The highest standard classification, typically manufactured using high-purity alumina fiber or polycrystalline alumina fiber formulations, engineered for the most demanding high-temperature applications — glass furnace crowns, specialty kiln hot zones, high-temperature laboratory and research furnace applications, and other processes operating at or near this upper temperature range. This grade typically carries a meaningfully higher cost than standard classifications, reflecting both the higher-purity raw materials required and the more demanding manufacturing process.

Choosing the Right Classification Temperature

A general engineering rule of thumb is to select a classification temperature with adequate margin above your application’s actual maximum continuous operating temperature — using fiber right at its classification limit tends to result in accelerated shrinkage and reduced service life compared to selecting a grade with reasonable headroom. Your specific margin requirement should account for your process’s normal operating temperature, any expected temperature excursions or upset conditions, and your facility’s tolerance for more frequent relining versus higher upfront material cost.

Density Options and What They Mean for Performance

Ceramic fiber blanket is available in a range of standard densities, each suited to different application requirements:

• Lower density blankets (approximately 64-96 kg/m³) — offer good insulating performance at lower material cost and weight, commonly used for backup insulation layers, less demanding general insulation applications, and situations where the blanket won’t be subject to significant mechanical stress or compression
• Medium density blankets (approximately 96-128 kg/m³) — a common general-purpose density balancing insulating performance, mechanical durability, and cost, widely specified across furnace lining, pipe wrapping, and general industrial insulation applications
• Higher density blankets (approximately 128-160 kg/m³) — offer improved mechanical stability, better resistance to erosion from gas velocity or handling stress, and are commonly specified for hot-face applications, higher-stress installations, or where the blanket will be compressed during installation (compression-fit installation methods rely on the blanket’s density and resilience to maintain effective sealing pressure against the installed surface)

Higher density generally also translates to marginally improved insulating performance per unit thickness, though the relationship isn’t perfectly linear, and the appropriate density selection should weigh mechanical performance requirements alongside pure thermal insulating value for your specific application.

Key Applications for Ceramic Fiber Blanket

Furnace and Kiln Backup Insulation

Ceramic fiber blanket is widely used as a backup insulation layer behind rigid hot-face refractory (brick, castable, or ceramic fiber board/module) in industrial furnaces and kilns, reducing heat loss through the furnace wall and lowering the outer shell temperature, without requiring the blanket itself to withstand the highest temperatures the furnace experiences at its hot face.

Furnace Hot-Face and Full-Thickness Lining

In many furnace designs — particularly where thermal cycling resistance and light weight are priorities over mechanical wear resistance — ceramic fiber blanket (often in folded module form for large industrial furnaces, or direct blanket application for smaller equipment) serves as the complete furnace lining, from hot face through to the outer shell.

High-Temperature Pipe and Duct Wrapping

Field-wrapped ceramic fiber blanket remains one of the most common methods for insulating high-temperature pipelines, flue gas ductwork, and process equipment, particularly for elbows, tees, valves, flanges, and other irregular geometry that pre-formed rigid insulation products cannot easily accommodate. Blanket is cut to size, wrapped around the pipe or fitting, secured with banding or wire, and typically finished with an outer metal cladding or weatherproof jacket.

Expansion Joint and Seal Packing

The flexibility and compressibility of ceramic fiber blanket make it a standard material for packing expansion joints between refractory sections in furnaces and kilns, accommodating thermal expansion movement while maintaining an effective thermal and gas seal at the joint.

Removable Insulation Jackets and Covers

Ceramic fiber blanket, typically encased in a durable outer fabric with closure hardware, is used to fabricate removable insulation covers for valves, flanges, and other components requiring periodic maintenance access — allowing full insulating performance during normal operation while permitting quick removal and reinstallation for inspection or repair work.

Fire Protection and Fire-Stopping

Certain ceramic fiber blanket products are used in passive fire protection applications, including fire-stopping around structural penetrations and as a component in fire-rated door and damper assemblies, leveraging the material’s high-temperature stability and non-combustible classification.

Laboratory and Research Furnace Insulation

Smaller laboratory furnaces, tube furnaces, and research heating equipment commonly use ceramic fiber blanket — often in combination with vacuum-formed shapes or rigid board — for chamber insulation, taking advantage of the material’s low thermal mass to support the fast heat-up and cool-down cycles typical of laboratory testing protocols.

Kiln Car and Shuttle Kiln Insulation

Periodic and shuttle kilns, along with kiln car top and side insulation in tunnel kiln applications, frequently use ceramic fiber blanket or blanket-based module systems, valued for the material’s ability to withstand the frequent thermal cycling inherent to batch and periodic kiln operation.

Automotive, Aerospace, and Specialty Manufacturing Equipment

Various specialty industrial heating equipment — including certain automotive exhaust component manufacturing processes, aerospace component heat treatment equipment, and other specialized industrial furnaces — use ceramic fiber blanket for compact, lightweight, high-performance insulation where equipment size and weight constraints make dense refractory impractical.

Boiler and Power Generation Equipment Insulation

High-temperature ductwork, expansion joints, and boiler casing insulation in power generation facilities commonly use ceramic fiber blanket, valued for its flexibility around complex geometries and reliable long-term thermal stability under continuous plant operating conditions.

Installation Methods

Wall and Roof Lining (Furnace/Kiln Construction)

For direct furnace or kiln wall and roof lining applications, ceramic fiber blanket is typically installed in a “shingle” or layered pattern, with successive blanket layers overlapped and compressed against the furnace shell using metallic or ceramic anchors. This layered, overlapped installation approach minimizes gaps and joints where heat could otherwise bypass the insulation, and the blanket’s inherent resilience allows it to maintain sealing contact against the anchoring system even as the material undergoes thermal cycling over its service life.

Pipe and Duct Wrapping

For pipe and duct insulation, blanket is cut to the appropriate width and length, wrapped around the pipe or fitting (in one or more layers depending on required thickness), and secured using stainless steel banding, wire, or insulation pins, typically finished with an outer weatherproof cladding for mechanical protection and moisture exclusion.

Module Construction (Large Furnace Walls)

For large industrial furnace and kiln walls, blanket is often factory-folded and compressed into modules — pre-assembled blocks of folded blanket fitted with internal anchoring hardware — which install directly onto the furnace shell as a faster, more consistent alternative to hand-layering individual blanket layers on site.

Cut-and-Fit Applications

For irregular equipment shapes, expansion joints, and custom sealing applications, blanket is cut and fitted by hand to the specific geometry involved, taking advantage of the material’s flexibility to accommodate shapes that would be impractical to address with rigid insulation products.

General Installation Best Practices

Protect installed blanket from moisture during and after installation, particularly for outdoor or humid-environment applications, using appropriate vapor barriers and weatherproof cladding as required by the specific application.

Ceramic Fiber Blanket Technical Parameters