Construction materials. Method for determining thermal conductivity coefficient

Standard Name: Building materials. Method of coefficient of conduction definition

Standard Number: ГОСТ 7076—66

Scope: This standard applies to building materials and establishes a method for determining the coefficient of thermal conductivity (in a dry state at temperatures on the hot surface of the sample from 25 to 700°C) by measuring the stationary heat flow passing through the test sample of the material using a low-inertia heat meter. The coefficient of thermal conductivity of a material is defined as the amount of heat passing through a sample of material with a thickness of 1 m and an area of 1 m² in 1 hour, with a temperature difference of 1°C on opposite (flat-parallel) sides of the sample. The coefficient of thermal conductivity is denoted by the Greek letter λ (lambda) and has the dimension kcal/m·h·°C (W/m·°C in the SI system).

Application: The method is intended for use in standards and technical specifications that establish technical requirements for building and thermal insulation materials and products.

Apparatus: The device for determining the thermal conductivity of building materials consists of a flat electric heater and a low-inertia heat meter installed 2 mm from the surface of the cooler, through which water flows continuously at a constant temperature. Thermocouples are embedded on the surfaces of the heater and the heat meter. The device is placed in a metal casing filled with thermal insulation, ensuring tight contact of the sample with the heat meter.