FIELD: measurement technology. SUBSTANCE: invention is intended for investigation of changes, mean integral by volume, of temperature of metal articles and billets. Gear has inductance coil 4 put on dielectric form 5 with round ferromagnetic screen 6. Rings of asbestos 7 and fluoroplastic 8 are attached to internal surface of form. Coil embraces part 1. Part is laid on fixing rest 2 and is machined with tool 3. Coil is connected by means of shielded cable 9 to input of test unit 10. Test unit includes capacitors 11 and 12, first 13, second 17 and third 23 stages of A C amplifier, filtering cell 15-16, voltage comparing unit 18, potentiometric divider 19-20, stabilized source 21 of rectified network voltage, two-way amplifier-limiter 22, ballast-limiting resistor 24, pointer-type voltage indicator 25 and recorder 26. EFFECT: enhanced objectivity and authenticity of measurement of temperature, mean integral by volume but instantaneous by time parameter, of metal articles under various types of their technological treatment. 2 cl, 2 dwg
