论文部分内容阅读
盐浴炉普遍地采用热电偶直接测温,当热电偶直接与高温盐浴接触时,在热电偶中发生干扰信号,而被输入到二次仪表中,使仪表增加误差。盐浴炉温度愈高,误差愈大。实际观测得知,当炉温>1000℃时,干扰信号使电子电位差计的温度指示高于实际炉温10～30℃。 1.干扰信号的产生 (1) 在高温状态下,绝缘材料的绝缘性能大大降低。热电偶直接置于有很大电流的盐浴内,相当于热电偶丝通过一个几K的电阻直接与盐浴接触,这就会有一定量的交流电流过热电偶。(2) 当变压器向盐浴炉
Salt bath furnace commonly used thermocouple direct temperature measurement, when the thermocouple in direct contact with the high temperature salt bath, the interference signal occurs in the thermocouple, and was input to the secondary instrument, so that the instrument increases the error. Salt bath temperature is higher, the greater the error. The actual observation that, when the furnace temperature> 1000 ℃, the interference signal so that the temperature of the electronic potentiometer instructions higher than the actual temperature 10 ~ 30 ℃. 1. Interference signal generation (1) At high temperature, the insulating material greatly reduces the insulating properties. The thermocouple is placed directly in a salt bath with a large current, which is equivalent to the thermocouple wire coming in direct contact with the salt bath through a few K of resistance, which results in a certain amount of overcurrent on the AC current. (2) When the transformer to the salt bath furnace