Furnace Insulation

The lining of a furnace (the layers of insulation inside its steel shell) decides how much of the heat stays inside and how much escapes. A good lining saves fuel or electricity, keeps the outside safe to stand next to, and helps the furnace heat evenly.

A lining in layers

Most furnace linings are built in layers, each chosen for the temperature it sees:

1. Hot face. The inner layer that faces the heat. It must handle the full temperature and any gas flow or wear. Board, modules or brick are common here.
2. Back-up layers. One or more layers behind it, at lower temperature. Blanket or board of a lower grade, chosen to stop as much heat as possible.
3. Steel shell. The outer case. A good lining keeps it cool enough to be safe and to stop the steel from warping.

Materials we supply

• Ceramic fibre blankets and modules
• Ceramic fibre boards
• Ceramic paper for seals and expansion joints
• Ceramic rope and tape for door seals
• Industrial ceramic parts such as element holders and tubes

Signs your lining needs work

• The outer shell is hotter than before, or has hot spots
• The furnace takes longer to reach temperature
• Fuel or power use has gone up
• Cracks, gaps or shrinkage can be seen inside
• Door seals let flames or heat out

Benefits of a fibre lining

• Less energy. Fibre stores far less heat than brick, so less energy goes into heating the walls.
• Faster cycles. The furnace heats up and cools down faster.
• Lighter. Less weight on the steel frame.
• Quick repairs. Damaged parts can often be cut out and replaced in a short stop.

Read our article on saving energy in industrial furnaces for more ideas.

How to order

Tell us the furnace type, its inside size, the working temperature, the fuel or heating type, and what the lining is made of now. Photos help. We will suggest materials and thicknesses. Contact us.