For this entry we would like to share a contribution prepared by Laura Oviedo from GTS Mexico. If you have interesting information related to heat treat that you want to share, do not hesitate to contact us. We will be happy to publish every value added article with the heat treat community.
A thermocouple is a sensing device that consists of two conductors of dissimilar electro thermal characteristics. The conductors are joined together at one end (hot junction), where the junction is placed in contact with the item whose temperature is to be measured. At the other end, cold junction, a voltmeter is used to measure the voltage that is produced by the difference in temperature between the two junctions.
- Base Metal Thermocouple: Thermocouple whose thermo elements are composed primarily of base metals and their alloys. Examples include K, E, N, J and T.
- Noble Metal Thermocouple: Thermocouple whose thermo elements are composed primarily of noble metals (example: platinum/platinum-rhodium) and their alloys. Examples include types R, S and B.
- What are the temperatures the sensor will be exposed to?
- What are the process specifications and allowable tolerances for error?
- How long is the measurement process expected to run?
- Are there any cost limits?
- Are the users experienced in proper sensor management?
Getting the right thermocouple in our industry can be a stressful task (and risky). That is why we have summarized the basic considerations in the following guideline that can be used when purchasing new thermocouples. Hoping you find it valuable!
