Mineral insulated resistance thermometers with a weld-in thermowell

Mineral insulated resistance thermometers with weld-in thermowell (53-WHD) are used for temperature measurement in gaseous and liquid media such as air, steam, water, oil, etc. with high current velocities and pressures. The material of the thermowell defines the operation temperature. Specialised thermowells are suitable up to 700 bar of pressure. The instruments of this product line are fitted with exchangeable mineral-insulated gauge slides.

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These sensors with a weld-in thermowell type D are often applied in high pressure steam lines and places where high flow rates apply. The weld-in thermowells are standard available with outside diameter 24h7 and 18h7 and can be inserted directly into the process piping.

The weld-in thermowells are available in different standard sizes. The bar stock thermowells can also be supplied in deviating sizes. Widely used materials are 1.7335 and 1.4571. If desired, the thermowells can be supplied with a 3.1 certificate.

The main construction component is a thermowell of high-grade or pressure-vessel steel, which is used to weld the thermometer into the respective machine.

Selection of the thermowell is dependent on spatial proportions at the point of installation, as well as demands as dictated by temperature, pressure, current flow and chemical attack.

Standard values for stress capacity can be found in the diagrams of DIN 43772.

In particular the question of chemical stress capacity must be examined carefully for each individual scenario. Often times, only field testing will yield authoritative information, as even minor impurities in the ambient media can have significant impact on the performance of the thermowell within the application environment.

For specialised applications (precision, long-term stability, etc.) we recommend the application of precision resistors with narrowed tolerance. Resistance values and tolerances of our resistance thermometers are pursuant to DIN EN 60751.

Application areas of our Mineral insulated resistance thermometers with a weld-in Thermowell (53-WDH)