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The analysis of the causes and research methods related to the failure of thermocouple sleeves in the article \"Causes of Thermocouple Sleeve Failure\" indicates that users prefer to avoid such failures. Changhui Instruments has summarized some preventive measures against thermocouple sleeve failures for reference. Precautions to prevent breakage of thermocouple sleeves: ① While meeting the general principles for material selection and applicable requirements, raise the material standards for thermocouple protection sleeves, such as using materials with better toughness and stronger corrosion resistance ； ②Thoroughly inspect the internal and external quality of the thermocouple sleeve, as well as the quality of its welding, to prevent improper welding from causing changes in the crystal structure of the sleeve material and resulting in crystalline cracks at the joint area ； ③Without compromising the requirements and accuracy of temperature measurement, the installation location and method of the thermocouple should be chosen carefully; for example, changing from vertical to inclined installation can alter the loading conditions on the protective sleeve ； ④A new type of leak-proof thermocouple is used; this type of thermocouple remains capable of preventing the leakage of fluid even when its protective sleeve is damaged ； ⑤To prevent the breakage of thermocouple sheaths caused by flow-induced vibration and resonance, measures such as increasing the damping of the sheath, thickening the wall thickness, and reducing the length of the sheath that protrudes can be appropriately employed for prevention ； ⑥To reduce the occurrence of vortex shedding in the fluid within the sleeve, the cross-sectional shape of the sleeve can be designed appropriately and streamlined surfaces can be used; furthermore, a vortex disruptor can be installed at the back of the sleeve within cost limits (Figure 1). http://yunrun.com.cn/upload/202002/05/202002051705243269.png Figure 1: Thermocouple sheath equipped with a disturbance device. Breakage of the thermocouple sheath is a common failure mode in the use of thermocouples. There are various reasons for such breakages; welding defects, vibration of the sheath, corrosion-induced detachment, improper material selection, and incorrect installation location or method are some of the most common causes. To prevent frequent occurrences of thermocouple sleeve breakage accidents, methods such as selecting materials scientifically, choosing welding processes appropriately, selecting the installation location and method for thermocouples wisely, increasing the damping of the sleeve as appropriate, determining wall thickness and protrusion length reasonably, designing the sleeve’s cross-sectional shape and streamlined surface properly, installing vortex disturbance devices inside the sleeve, and using new types of leak-proof thermocouples can be employed. Reasons for thermocouple sleeve breakage http://yunrun.com.cn/tech/2904.html