表面型熱電偶之量測與應用

溫度量測是各項量測的基礎，熱電偶溫度計是最常用的工具之一。熱電偶感測頭型式有片狀型、線圈型、滾輪型、平板型、磁吸型等多種型式，而熱電偶線及補償導線的種類有K, E, J, T, R, B, S, N, C等九種。本研究特別針對表面型K-type熱電偶線，感測點依不同的焊接接點型式、熱電偶線的尺寸(寬度與厚度)、感測頭型式(單片型、三片型、線圈型、滾輪型)等，探討正確量測方法對表面溫度之量測誤差與反應速率的影響。研究結果顯示：(1)感測頭的焊接接點型式並不會影響溫度量測的精確度與反應速率；(2)熱電偶線的尺寸(寬度與厚度)與量測的精度無關，但會影響反應速率；寬度愈窄或厚度愈薄，反應速率愈快；(3)單片型與三片型感測頭均能精確的量測溫度，但單片型會因人員操作不當，造成感測點偏移；三片型則因兩側有支撐，而不會導致溫度測量的誤差。(4)線圈型感測頭的反應速率比片狀型要慢，但較能耐高溫、富彈性而壽命長，且能應用在不平整的表面；(5)滾輪型熱電偶在滾動狀態下的反應速率較靜止狀態下為快，但必須考慮表面摩擦係數的問題。

關鍵字

感測頭；補償導線；表面型K-type熱電偶線；焊接接點；反應速率

並列摘要

Temperature measuring is the basis of various measurements. Thermocouple is a widely used device for measuring temperature with various forms of sensing elements on one end, such as slice type, coil type, roller type, board type, and magnetic type, etc. There are 9 calibration types --- K, E, J, T, R, B, S, N, and C --- for thermocouple wire and compensation wire. This research focuses on the measuring error and response rate of surface-type thermocouples (K type) including the correct measuring methods, the types of welding joint type, the dimensions of thermocouple wire (width and thickness), and the types of sensing elements (single slice type, triple slice type, coil type, and roller type). Study results show: (1) the accuracy and response rate are not influenced by the types of welding joint. (2) the dimensions (width and thickness) of thermocouple wire is irrelevant to the accuracy, but is relevant to the response rate: the narrower or the thinner, the quicker. (3) both single slice type and triple slice type can precisely measure the temperature, however, single slice type may result in deviation from testing point and inaccuracy because of the worker’s inappropriate operation. The triple slice type will not, in view of the extra support from the both slices next to the sensing one. (4) coil type is slower than that of slice type on response rate, but coil type can endure higher temperature, be more flexible, last longer, and apply on the rugged surface. (5) roller type responses faster when is applied on rolling surface than on static status, but friction coefficient needs to be taken into consideration for accuracy.

並列關鍵字

sensing elements ； compensation wire ； surface-type thermocouple ； welding joint ； response rate

參考文獻

6.O. Yu. Titov, G. Gonzalez dela Cruz, G. N. Logvinov, New Physical Point of View on the Peltier effect, 16th International Conference on Thermoelectric, 1997 pp.661-663.

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1.大森豐明，感測器技術的基礎和應用，建宏出版社，1997.