If the bimetallic thermometer and the protective sleeve are not matched, can it still be used accurately?
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With a short bimetallic thermometer and a long protective sleeve, can the temperature be measured accurately?/
There will be variations in temperature; it’s better to use another thermometer. Even with thermal oil added inside the sleeve, differences still exist
;P:L:L:Q:D:D
It depends on the specific manufacturing process and the range of measurement – these factors have an impact.
If the protective sleeve was used previously, meaning that the thermometer was inserted at a greater depth back then compared to the current bimetallic thermometer, then the current readings will be lower; this is especially true when measuring in storage tanks, where the temperature will be lower than it was before. If the previous protective sleeve was short and no suitable one is available for replacement, so a longer one is used, then the temperature displayed will not differ much from before.
If the protective sleeve is long and the bimetallic thermometer is short, then the bimetallic thermometer does not come into direct contact with the substance being measured; instead, it measures the temperature of the air inside the protective sleeve. Won’t this result in errors?
Bimetallic elements and thermocouples are similar in function; what’s important is the depth of insertion. Generally, it’s necessary to insert them to the center of the pipe. If the protective tube is short while the thermometer is long, it will be impossible to install them properly. In that case, the flange will need to be made longer. If the insertion depth isn’t sufficient, it will affect the accuracy of temperature measurement
An overly long protective tube causes a significant delay in the temperature readings provided by the thermometer. The thermometer itself already has a delay in its reading process, and with such a large cavity present, it becomes difficult to obtain accurate measurements; the sensitivity also decreases considerably.
It won’t give an accurate reading, because there is a section filled with air; we have conducted experiments here by repeatedly swapping out the thermometers