Thermal Conductivity Technology for Leak Detection

Thermal Conductivity

• Thermal conductivity is the transfer of heat or energy within a material though there is no motion of the material. Gases, for instance, transfer heat by the direct collisions of molecules. The transfer of heat during these collisions is much less than in solid materials because the gas is so dilute. In metallic solids, the thermal conductivity is high because metal is a good electrical conductor as well. Non-metallic solids would have a different rate of thermal conductivity.

Thermal Conductivity Technology

• A variety of instruments are available to measure the thermal conductivity or heat transfer in a material. The rate of thermal transfer allows the operator to determine not only how quickly the heat is being transferred, but also what kind of material it is, because all materials have their own rate of transfer. Thermal conductivity is measured as a certain amount of heat that passes in a unit of time through a certain amount of area of the material. The instruments that measure thermal conductivity are very sensitive and can be used to find leaks deep within internal parts or even underground.

Leak Detection

• Generally, thermal conductivity leak detection technologies detect minute leaks of any gas with thermal conductivity values different from air. A reference inlet draws in ambient air and compares it to the gas that is drawn into the sampling probe. Depending on the sensitivity of the technology, it can detect such gases as helium, nitrogen, carbon dioxide, argon and other gases. Thermal conductivity technology can also be used to find inadequacies in building insulation and leaks in refrigerants.

Other Uses

• Besides its use for detection of gas leaks in the home setting, thermal conductivity technology is used extensively in industrial fields to prevent the buildup of dangerous gases and to prevent loss of valuable materials. New uses for this technology will no doubt continue to expand to create more efficient systems for both the home and industry.