Device for measuring thermal conductivity coefft. of quenchants - using capillary tube with fine wires connected to regulating and measuring units

摘要

Thermal conductivity coefft. of quenchants used in heat treatment of metals is measured by an arrangement of an electrically heated capillary tube (3), along which four fine wires (1,2) are welded, two (1) of which are connected to a control unit (7,8) to regulate current and thus the mean temp. of the tube. The inner wires (2) are connected to a device (7) for measurement of resistance and thus temp. of the tube. ADVANTAGE - Eliminates effects of parasitic axial heat flows to improve measurement accuracy.