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8 Handling
8.2.3
Welded-stem thermometer
The quality of the welded joint plays a crucial role in determining the leak-tightness and strength of the
construction.
WARNING!
Personal injury and damage to property due to a poor-quality welded joint!
Poor-quality welded joints in combination with high pressure or overheating can cause leaks. If touched,
these can cause burns or destroy the device.
Have welding work on thermometers carried out by adequately trained personnel only. Make sure
that the personnel are familiar with and understand the contents of the operating manual. Any safety
information and notes on proper use are particularly important.
8.2.4
Mineral-insulated thermocouples and RTD temperature probes
Mineral-insulated thermocouples and RTD temperature probes can be bent. The bending radius must
be at least five times the diameter (R ≥ 5D). When bending the devices, ensure no load is exerted on the
connection point of the adapter sleeve (to the rigid part of the protection tube). A minimum distance of
15 mm from the bend must be maintained in this respect.
With mineral-insulated thermocouples, the ideal solution is to select a suitable thermal cable. It is also
possible to use compensating cables provided they have been selected very carefully.
With mineral-insulated thermocouples, measurement deviations should be prevented by means of insu-
lation on the adapter sleeve or connection points.
Observe the maximum temperatures for the adapter sleeve and any adhesive used.
8.2.5
Surface probe for surface measurements
In addition to temperature probes (which are immersed into the media being measured), surface probes
are also available.
Observe the following points when mounting surface probes:
•
The measurement surfaces must lie flat against one another
•
The contact surfaces must be free of corrosion; clean them before starting the mounting work
•
Insulate the measuring point incl. the surface probe accordingly to prevent heat dissipation
•
A constant ambient temperature is desirable/there should be no impact on the measurement object
from convection caused by equipment such as fans or air conditioning systems
•
Securely fasten the surface probe to the pipe, applying the correct contact pressure
•
To improve the measurement result, use heat-conducting paste in the area of the contact point
•
Mount the device a minimum of 10 cm from pipe bends, radial weld seams, and similar
