Aluminum Silicate Fiber Felt for Furnace and Kiln Lining – 1260–1430°C Insulation

Aluminum Silicate Fiber Felt Applications

• Steel Reheating and Heat Treatment Furnaces – Aluminum Silicate Fiber Felt Lining

  ✅Key Advantages

  1. Aluminum silicate fiber felt reduces shell temperature and heat loss in walking-beam and pusher furnaces, supporting energy savings of several percent compared with dense refractories alone.

  2. High-temperature grades with 1260–1430 °C classification temperatures withstand furnace roof and burner zone conditions in steel heating operations.

  3. Flexible felt construction allows easy maintenance of burner blocks, doors and flue openings without extensive brick demolition.

  ✅ Problem Solved

  A steel plant retrofitting a 1200 °C reheating furnace replaced part of its dense refractories with aluminum silicate fiber felt and modules on the roof and sidewalls. Measured heat loss through the shell dropped enough to reduce annual fuel consumption by approximately 3–5%, and shell temperature at critical points decreased by 20–30 °C, lowering thermal stress on the steel structure and extending maintenance intervals from yearly to every 18–24 months. Production stayed within the same temperature uniformity tolerance while the lighter lining shortened heat-up time after scheduled shutdowns.

• Power Plant Boilers and HRSG – Aluminum Silicate Fiber Felt for Casing and Ducts

  ✅Key Advantages

  1. Aluminum silicate fiber felt provides low thermal conductivity around 0.16–0.20 W/m·K at 800–1000 °C, which is important for boiler wall and gas duct insulation.

  2. Lightweight density levels between 96 and 128 kg/m³ help reduce load on casing structures while maintaining required surface temperature limits.

  3. Flexible felt and pads are easy to adapt around stiffeners, nozzles and manholes during boiler or HRSG installation and retrofit.

  ✅ Problem Solved

  A power plant operating a multi-pressure HRSG needed to keep outer casing temperatures below 60 °C in compliance with site safety rules. By installing 50 mm aluminum silicate fiber felt at 128 kg/m³ density behind metal cladding in the hottest duct sections, the plant achieved the target surface temperature with a single insulation layer and avoided adding heavier rigid insulation. Thermal calculations confirmed that the chosen felt grade met design requirements, and on-site measurements during full load operation verified surface temperatures within specification without additional stiffening of the casing.

• Petrochemical Fired Heaters – Aluminum Silicate Fiber Felt Back-Up Insulation

  ✅  Key Advantages

  1. Aluminum silicate fiber felt used behind refractory linings helps limit temperature at the heater shell and supports long-term operation near design duty.

  2. Controlled shrinkage at high temperature reduces risk of gaps forming behind castables and bricks when the heater cycles between start-up and turndown conditions.

  3. AES bio-soluble aluminum silicate fiber felt options support compliance with more restrictive occupational exposure rules in modern refineries.

  ✅  Problem Solved

  During a fired heater revamp, a petrochemical plant specified aluminum silicate fiber felt as a back-up layer behind refractory bricks in the convection and radiant sections. The combination reduced external steel temperatures to the specified design window while minimising total lining thickness. After several years of operation at typical outlet temperatures near 900–950 °C, inspection during a turnaround showed the fiber felt still in place with no significant voids, and the heater shell had not experienced abnormal deformation, confirming that the felt grade and density were adequate for the service conditions.

Aluminum Silicate Ceramic Fiber Felt Product Usage Guide

• Installation

  1. Verify the design drawing for aluminum silicate fiber felt thickness, density and layout before installation.
  2. Cut felt with sharp knives or dedicated cutting tools to match doors, burner blocks, flanges and curves; avoid tearing to keep edges clean.
  3. Install aluminum silicate fiber felt with recommended anchors, pins or adhesive systems, ensuring tight contact with the shell and neighbouring pieces.
  4. Stagger joints and avoid continuous straight gaps; compress felt slightly where necessary to compensate for future shrinkage at temperature.

• Use in service

  1. Follow specified heat-up curves to dry any binders and coatings gradually and reduce thermal shock in the new lining.
  2. Monitor shell temperature and compare with design values during the first production cycles; adjust loading or firing if temperatures exceed limits.
  3. Inspect doors, burner tiles and joint areas regularly, as these zones experience higher movement and thermal cycling.

• Storage

  1. Store aluminum silicate fiber felt in dry, covered areas, away from rain and standing water.
  2. Keep rolls and panels in original packaging until just before cutting to minimise dust and contamination.
  3. Avoid stacking heavy items on top of felt cartons to prevent permanent compression before use.

• Cleaning and maintenance

  1. Use industrial vacuum systems to remove loose fibers and dust from installation areas.
  2. For minor damage, patch with matching aluminum silicate fiber felt strips and secure them with appropriate fasteners or coatings.
  3. When larger areas are degraded, cut back to sound material and install new felt with overlapping joints to restore insulation performance.

• Common misuse points and handling suggestions

  1. Over-compression during installation
  Problem: Excessive compression of fiber felt reduces thickness and can increase thermal conductivity in service.
  Handling: Follow design compression limits, typically only light compression to ensure contact, and avoid using felt as a structural load-bearing layer.

  2. Using low-temperature grades in high-temperature zones
  Problem: Selecting 1100 °C grade aluminum silicate fiber felt for areas exposed to 1260–1300 °C gas temperature can lead to early shrinkage and gaps. Alibaba+1
  Handling: Match classification temperature of the felt to the expected hot-face temperature with margin, and use high-alumina or ZA grades where necessary.

  3. Insufficient joint sealing
  Problem: Leaving open butt joints or misaligned seams allows hot gas leakage and local overheating of the shell.
  Handling: Overlap joints, use offset layer arrangements, and add ceramic fiber paper or strips over critical seams to improve sealing.

FAQ – Aluminum Silicate Ceramic Fiber Felt

1. Q: What is the maximum service temperature of aluminum silicate fiber felt?
   A: Typical aluminium silicate fiber felt grades have classification temperatures between 1260 °C and 1430 °C, with recommended continuous operating temperatures slightly below these limits depending on the design.
2. Q: How does aluminum silicate fiber felt compare to rock wool or calcium silicate insulation?
   A: Aluminum silicate fibre felt offers higher service temperature and lower thermal mass than rock wool or calcium silicate, so it is preferred for furnaces and heaters operating above 900–1000 °C, while rock wool and calcium silicate are mainly used in lower-temperature piping and equipment.
3. Q: What density of aluminium silicate fiber felt should I select for my furnace lining?
   A: Many furnace and kiln designs use 96–128 kg/m³ aluminum silicate fiber felt as lining or back-up insulation, while 160 kg/m³ grades are used where higher mechanical strength or lower shrinkage is required; the final selection depends on shell temperature, gas velocity and mechanical constraints.
4. Q: What is the typical thermal conductivity of aluminum silicate fiber felt?
   A: At a density of about 128 kg/m³, aluminium silicate fibre felt shows typical thermal conductivity values around 0.09 W/m·K at 400 °C and 0.16–0.20 W/m·K at 800–1000 °C, which allows thin linings to achieve significant energy savings.
5. Q: Can aluminum silicate fiber felt be supplied in bio-soluble AES grades?
   A: Yes, aluminium silicate fiber felt can be produced from AES (alkaline earth silicate) fibers that are bio-soluble and designed to meet more stringent occupational exposure regulations while maintaining comparable insulation performance.
6. Q: How is aluminium silicate fiber felt installed in a furnace or boiler?
   A: Aluminum silicate fibre felt is typically fixed with welded anchors, pins and washers or with refractory adhesives, with joints staggered and layers overlapped to minimise hot gas leakage and maintain continuous insulation.

Aluminum Silicate Fiber Felt Reviews

• ⭐️⭐️⭐️⭐️⭐️
  Our team used the aluminum silicate fiber felt during a roof repair, and the insulation performance stayed stable even at high firing rates. The cut pieces matched our drawings exactly.
  -- Mark Jensen – Furnace Supervisor, Delta Steel Processing
• ⭐️⭐️⭐️⭐️⭐️
  We ordered custom aluminum silicate ceramic fiber felt pads for several kiln builds, and the dimensional accuracy was consistent across batches. The material handled thermal cycling very well.
  -- Elena Rossi – Project Engineer, ThermoKiln Systems
• ⭐️⭐️⭐️⭐️⭐️
  The aluminum silicate ceramic fibre felt helped us achieve the required casing temperature on an HRSG retrofit. Its low thermal conductivity made the design calculations easier to meet.
  -- David Kim – Technical Manager, Horizon Power Boilers
• ⭐️⭐️⭐️⭐️⭐️
  We have used aluminium silicate fibre insulation for door seals and burner areas, and the service life has noticeably improved. ADCERAX supported the custom sizes with quick engineering feedback.
  -- Ahmed Sabry – Operations Director, Gulf Industrial Heaters