Thermowells for temperature sensors in different industrial applications
A thermowell is the wetted part of a thermometer that protects the temperature sensor from harsh process conditions such as high pressure, high velocity flow and corrosion when the thermometer cannot be placed directly in the medium. The thermowell also ensures that the measurement insert can be replaced without interrupting the process. Basically, thermowells are divided into protection tubes constructed from welded tubes and thermowells made of drilled bar stock material.
Our huge portfolio of perssure-tight thermowells comprises:
Threaded, weld-in, compression fitted and flanged process connections for all industrial applications
In process automation, two measurement principles for temperature have asserted themselves as a standard
Measuring principle: Resistance temperature detectors (RTDs)
The RTD sensor changes its electrical resistance with a change in temperature. They are suitable for the measurement of temperatures between -200 °C and approx. 600 °C and stand out due to high measurement accuracy and long-term stability. The most frequently used RTD types are a Pt100 or a PT1000. As a standard, Endress+Hauser RTD sensors fulfill the IEC 60751 accuracy class A.
Measuring principle: Thermocouples (TC)
A thermocouple is a component made of two different metals connected with each other at one end. An electrical potential (thermoelectric force) is caused due to the Seebeck effect at the open end if the connection and the free ends are exposed to different temperatures. With the help of the so-called thermocouples reference tables (see IEC 60584) the temperature at the connection (measuring junction) can be concluded.
Thermocouples are suitable for temperature measurement in the range of 0 °C to +1,800 °C. They stand out due to the fast response time and high vibration resistance.
Increases the life cycle of the measurement insert through protection against process influence
Allows measurement insert exchange under harsh process conditions
Mechanical stability against pressure and flow