| 摘要 |
An apparatus for testing the quench-cooling properties of a liquid quenchant comprising a thermistor adapted to be immersed in the liquid to be tested, means for applying an electric potential across the thermistor comprising means for applying an excitation voltage to electrical bridge circuit which contains the thermistor in one leg thereof, first timing means controlling the duration of time during which said excitation voltage is applied to said bridge circuit and means for determining the electrical resistance the thermistor, such that the quenchant properties of the liquid tested are determinable by comparison of the resistance of the immersed thermistor with at least one reference resistance value. A process is provided for testing liquid quenchants, particularly used quenchants which can be restored to their original properties by the addition of additives or solvents such as water. |
