Wear-resistant thermocouples in cement plants keep breaking; what factors can cause breaks of the kind shown in the image?
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Purchase a batch of K-type wear-resistant thermocouples for customers, with a temperature range of 0–1200°C, an insertion depth of 900, wear resistance up to 650, a diameter of 20, intended for use in cement plants. Please take a look at the picture; the on-site feedback shows that its usage life is short – it breaks down basically within a week. However, it can be used by other cement plants for over a month. In this particular cement plant, problems similar to those shown in the pictures have occurred. Is there anyone who knows about this? Please give some guidance on how to deal with it – or could this be intentional damage?
This post was last edited by Xiaobai_WPIO on 2018-7-14 19:22 with images
If this thing breaks, replace it; good ones are expensive.
I really can’t find anything that will last a month; come to me then
There must be vibration as well; systematic design and selection are necessary – just relying on the thermometer alone is not enough
I guess it got broken in a collision — there was a wild boar in the furnace; its skin burned from the heat, so it ran around chaotically and broke the thin shaft of the thermocouple. . . . . . Bold, bold – a thick thermocouple all around the bucket, so that the pig can touch it easily.
The pictures you took don’t seem to show wear and tear, but rather breaks. Is it a material issue?
This is due to the thermocouple being too long; prolonged stress has caused this issue. As you can see, there’s no break in that section, so that’s fine. One possible reason is the material used, and another is the excessive length of the thermocouple. It seems that your installation uses flanges, and there should be a sleeve inside; you might consider lengthening that sleeve. I suspect that the length of the sleeve happens to be exactly at the point where it broke – the back-and-forth vibrations caused the top end of the sleeve to act as a pivot point, and over time, that’s where the break occurred. In fact, the part that needs to be exposed is only 3-5 centimeters long, so just exposing that portion will suffice
Or you could consider making a front-end sealed sleeve
It seems to be a fracture rather than wear: 1. Provide the process flow rate at that location to the manufacturer so that they can calculate the vibration intensity of the casing； Generally, for sleeves of this length, manufacturers rarely carry out overall drilling to form them; it is possible to suggest that the manufacturer change the method of sleeve processing, and based on the calculation results, a conical shape or something similar could be chosen ； Or increase the wall thickness of the casing to ensure strength ； 2. Can we discuss this with the process team to change the temperature measurement point and select one where the process flow rate is lower? ；