多区加热热电偶检定炉的温场研究

Research on Temperature Uniformity of the Calibration Furnace with Multiple Calorifiers

针对在热电偶检定过程中使用传统的检定炉用均温块所导致的控温滞后、恒温时间长、漏电及炉管弯曲等问题,研制出不用均温块温场也能满足相关规范要求的多区加热检定炉,以提高检测效率。根据JJF 1184-2007《热电偶检定炉温度场测试技术规范》对用均温块的传统单区加热检定炉与不用均温块的多区加热检定炉的温场分别进行测试;再用热电偶示值误差试验进行对比验证。结果表明,在400~1000℃温度范围内的各个校准点,不用均温块的多区加热检定炉在轴向温度场、径向温度场、热电偶示值误差等各项测试中,指标均优于用均温块的传统单区加热检定炉。

In the process of thermocouple calibration,there are some problems such as temperature control lag,long constant temperature time,electric leakage and furnace tube bending caused by using the traditional thermostatic block for calibration furnace.Therefore,a calibration furnace with multiple calorifiers which can meet the requirements of relevant specifications without the temperature uniformity of the thermostatic block has been developed to improve the calibration efficiency.Firstly,according to JJF 1184-2007 Testing Specifications for Temperature Uniformity in Thermocouple Calibration Furnaces,the temperature uniformity of the traditional calibration furnace with single calorifier equipped with the thermostatic block and the calibration furnace with multiple calorifiers without the thermostatic block are tested respectively.Secondly,the two kinds of temperature uniformity are compared and verified by thermocouple indication error test.The results show that in the temperature range of 400~1000℃,the calibration furnace with multiple calorifiers without the thermostatic block is superior to the traditional calibration furnace with single calorifier equipped with the thermostatic block in the axial temperature uniformity,radial temperature uniformity,thermocouple indication error and other tests.