Platinum Metals Rev., 1967, 11, (2), 49
The Selection and Use of Thermocouple Sheaths
Without adequate protection from the relatively few substances that can contaminate them, platinum thermocouples can deteriorate rapidly. Given such protection, in the form of a carefully chosen refractory sheath properly looked after, they will give long and reliable service at high temperatures often in apparently adverse conditions. The subject of sheath materials and design is a somewhat neglected one, and it is valuable to have available a survey of the variety of old and newer sheath materials that can be used in the many applications of thermocouples in metallurgical processes. D. W. Brown, of Morganite Research and Development, has provided such a review (J. Inst. Metals, 1967, 95, 12–17), together with useful guidance on such important details as the size and positioning of sheaths in various types of furnaces and their careful handling in service.