Means and techniques for testing of heat insulation materials

Insulation testing apparatus comprising, a single heat source;

• said heat source being a single elongated electrical heating element;
• said heat source being metal-clad along its length by a high heat conductivity metal material which is in good heat conducting relationship to said heating element and which is internally heated by said element such that the temperature of said metal material is substantially uniform along its length;
• metal material which is heated by said elongated electrical element with said two insulating materials each having an inner surface and an outer surface and with said inner surface of each insulating material being in direct contact with said metal material without any air space therebetween;
• means for measuring the difference in the quantity of heat conducted through said different insulating materials;
• said measuring means including a first thermopile means and a second thermopile means mounted on wall means in said apparatus and in thermal contact respectively with a corresponding outer surface of said two insulating materials without any air space therebetween such that heat flows solely by conduction and without radiation or convection from the heated metal-clad heat source through each of said two insulating materials to a corresponding one of said thermopile means, said first thermopile means measuring the amount of heat passing through one of said materials;
• and said second thermopile means measuring the amount of heat flowing through the other one of said insulating materials.