Commissioning, Operation - WIKA TW45 Mode D'emploi

5. Transport, packaging and storage / 6. Commissioning, operation
5.3 Storage
Avoid exposure to the following factors:
Direct sunlight or proximity to hot objects (for thermowells with plastic coating)
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Mechanical vibration, mechanical shock (putting it down hard)
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WARNING!
Before storing the thermowell (following operation), remove any residual media. This
is of particular importance if the medium is hazardous to health, e.g. caustic, toxic,
carcinogenic, radioactive, etc.

6. Commissioning, operation

6.1 Mounting
During mounting the thermowells should not be subjected to thermal shocks or mechanical
impacts.
Insert the thermowell into the process adapter without forcing or damaging it. The thermowell
must not be bent or altered in order to mount it.
The exception is the retrospective machining of the support ring in order that the thermowell is
supported free of play within the nozzle ("interference fit"). The retrospective adjustment of a
support ring with a loose fit is not permissible. In general, thermowells with a support ring are not
recommended within ASME PTC 19.3 TW-2016 and are outside of the scope of the standard.
Installation notes for ceramic thermowells
The C 799 ceramic material is only partially resistant to changes in temperature. A tempe-
rature shock can therefore easily result in stress cracks and consequently in damage to the
ceramic thermowell. For this reason, thermometers with thermowells of C 799 ceramic must be
pre-heated before installation, and then slowly inserted into the process.
Depending on the ambient and process temperatures present, this procedure is also
recommended for the other ceramic materials. In addition to the protection from thermal stress,
ceramic thermowells must also be protected from mechanical stress. Such damaging stress
conditions are caused by bending forces acting in a horizontal installation position. Thus, with
horizontal installation (and dependent upon diameter, nominal length and design), additional
support should be provided by the customer.
The note regarding the problems caused by bending forces also applies, in principle, to metal
thermowells.
WIKA operating instructions thermowells
EN
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