Why is temperature recorded in addition to the ultrasonic signal when testing steam traps?

When testing a steam trap, the ultrasonic signal provides information about the acoustic processes occurring within the component. The additional temperature measurement helps record the thermal operating conditions of the steam trap and provides further context for the ultrasonic measurement.

For this purpose, the BS20 structure-borne sound and temperature sensor features an integrated infrared temperature sensor.

What information does the temperature measurement provide?

The measured surface temperature provides additional information about the current operating conditions of the steam trap and steam line.

For example, it can help assess whether the measurement is being performed under plausible thermal operating conditions.

Temperature does not replace the ultrasonic measurement. The available measurement and operating data are considered together when assessing the steam trap.

How is the temperature measured?

Temperature is measured without contact at the surface of the test object using the BS20's integrated infrared sensor.

The sensor's measurement range is:

−70 °C to +380 °C object temperature

For reliable measurement results, the temperature sensor must be correctly aligned with the measurement surface.

What role does emissivity play?

With non-contact infrared temperature measurement, the result depends on the properties of the measured surface. The emissivity of the test object must therefore be taken into account.

Painted or oxidized surfaces often have an emissivity of approximately 0.9. Different values may be required for other materials.

A contaminated temperature sensor or unsuitable positioning can also affect the measurement result.

Temperature should therefore be treated as an additional measurement variable and evaluated together with the ultrasonic signal and the known operating conditions of the steam trap.