Abstract: A test device for measuring the thermal conductivity of materials by hot-wire method was designed and used to test the thermal conductivity coefficient of a bulk sulfide ore of six size fractions 0~1，1~2，2~4，4~6，6~8，8~10 mm at 25～120 ℃.The test results show the thermal conductivity complexity and nonlinearity of bulk materials: the thermal conductivity coefficients of all size fractions slowly increase with the temperature rise in basically a linear relation within the test temperature scope, and at the same temperature, their relation curve with particle size is on the whole similar to a parabola.It is seen from the error analysis the total error of each measurement is within 4%, which is mainly due to the prediction equation for thermal conductivity coefficient, the idealized processing of hot-wire resistance and the inherent error of current and temperature measuring instrument, where resistance and current contribute the most.

Key words: Sulfide ore, Hot-wire method, Thermal conductivity, Inaccuracy analysis