WAM® LK 40-18 LW – Low Conductivity Lightweight Castable

WAM® LK 40-18 LW is a lightweight castable with approximately a 40 pound per cubic foot density and a 1800oF maximum operating temperature limit. The WAM® LK series of lightweights is designed to provide greater insulating character, lower thermal conductivity, compared to the non LK lightweights. In general the lower the density the greater the insulating capability of the material.


Lightweight castables are primarily used as insulating backup linings. However, they can be used as working linings in non contact areas such as roofs. In some cases it is appropriate to use lightweights in contact areas but one should discuss the specific application with your technical sales representative to determine if appropriate for the specific product and the contact material.


Depending on your specific thermal and contact needs your WAM® representative will recommend a combination of insulating backup materials and hot face or working lining materials to fit your needs. Design of furnace lining configurations to achieve energy usage goals is an area we excel, particularly in aluminum contact applications.  We use a proprietary thermal program to ensure proper shell temperatures, freeze plan locations and energy savings for your process.

Typical Technical Data
WAM® LK 40-18 LW                                                                             PDF Download

Classification:Light Weight Castable
Placement Method:Vibration Casting, Gunning*
Available Application Packages:G - Gunning Mix
AL - Aluminum Penetration Resistant
* G Add On Package Required
Typical Water Requirement (%wt):95
Material Required for Estimating (lb/ft3):39
Maximum Recommended Service Temperature (°F):1800

Calculated wt.% Based on Common Oxides

Aluminum Oxide (Al2O3):32.9 %
Silicon Dioxide (SiO2):46.6 %
Titanium Dioxide (TiO2):0.9 %
Iron(III) Oxide (Fe2O3):0.9 %
Calcium Oxide (CaO):15.8 %
Magnesium Oxide (MgO):0.2 %
Combined Alkali Oxide (Na2O + K2O):2.7 %


Modulus of
Rupture (psi)
Cold Crushing
Strength (psi)
Linear Change (%)
After 23043310460n/a
After 150039180270-0.5
After 1800n/an/an/a-0.7

Additional technical data may be available. Please contact your sales representative for more information.
Data on this table represent typical properties and cannot be used for specification purposes.