Breakage of the armored sheath of multi-point thermocouples
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Dear experts, I would like to ask for your advice. Our unit uses multi-point thermocouples in converters, where the temperature reaches around 200°C. These thermocouples are enclosed in protective sleeves; the material of these sleeves is 304SS. However, after a few months of use, the sleeves start to break, as shown in the image below. After switching to another supplier in accordance with the technical specifications, such problems have not occurred again. I would like to know the exact reason for the breakdown of the thermocouple sleeves. I appreciate any guidance you can provide
The explanation is that it’s your first supplier whose materials have problems
I asked around, and this situation is indeed rare. Moreover, it’s the first time such a thing has happened with a relatively well-known company in China; the temperature involved is over 100 degrees, and there’s also a 316 protection sleeve outside, so it shouldn’t break after just one use. It’s really strange
We also produce this product, and such issues usually arise due to problems with the materials or the annealing process
Big bro, did you end up buying a fake product? How can a big brand have such poor quality and still manage to grow to such a large scale?
The converter is unknown what it is. How deep should the sleeve be inserted? Medium flow rate? For long insert depths, high flow rates, and special cases, resonance calculations and stress calculations are required. Improper material selection and manufacturing can easily lead to the breakage of the connection
This is a thermocouple with multiple elements enclosed in a protective casing, used in converters. As can be seen from the second photo, the damage is clearly caused by radial forces; it is best to use a 316SS casing. If it contains sulfur, choose 321SS or 347SS material ； If installed on a pipe (which is unlikely), it is necessary to conduct frequency vibration calculations for the casing, as well as assess stress failure under special conditions such as high flow rates, which could lead to resonance-induced fracture.
It must have been that worker taking out his anger, or some spy causing trouble, who broke it. Looking for a material-related reason is a bit far-fetched. .
Is it a well-known brand? Is it a factory in Shanghai? The water is very deep
The wires used in our boilers also break frequently; we’re not sure what’s going on
If this happens when used in a gas boiler, it’s not surprising