Frequently Asked Questions
1) Is it OK to twist the tip prior to welding the end?
The short answer is that twisting is not a good idea. The way a thermocouple works is that it reads from the first point in which the two metals touch one another. By twisting that is moving your first connection point farther away from the tip.That means that your calibration will not be as accurate as your standard used to compare against the thermocouple will be farther up in the drywell unintentionally causing a deviation between thermocouple calibration and standard reading.
The twist can also become untwisted causing the reading to move to the next connection point. This will have an effect creating potentially erratic readings, or even an open thermocouple. In general your thermocouple will not be as accurate as it should be.
2) Is it OK to use an arc welder to weld the two ends together?
It is an option.There are a few downsides. Arc welding typically leaves a fairly large bulb of material for the tip. It also dampens the reading since there is more material that absorbs the temperature differences. Arc welding the tip also leaves a lot of soot in the weld which can have an effect on the reading since now there is an additional element in the equation.
3) Is it OK to solder my thermocouples instead of welding?
This is not often seen, but is brought up often. The point of a thermocouple is that the two materials have a certain reaction to the changing in temperature when they are connected together. Using solder adds a 3rd material which can have a variety of effects on the reading of the thermocouple.