WIKA TR75 - Manual (Page 19)

11325232.04 01/2014 GB/D/F/E
WIKA operating instructions DiwiTherm ® , model TR75 19
GB
3. Position the indicator as required, tighten the hexagon bolts and slotted screws, and finally
tighten the lock nut or union nut firmly.
Observe the following points during sensor installation:
■ If possible, the entire length of the sensor should be exposed to the temperature being
measured.
■ In pipelines or at other measuring points, the temperature sensor should be directed as
far towards the flow as possible.
■ When using thermowells, fill a thermal contact medium in order to reduce the heat
transfer resistance between the outer wall of the sensor and the inner wall of the
thermowell if possible. The working temperature of the heat conductive paste is
-40 ... +200 °C.
WARNING!
Do not use any heat transfer oil!
6.1 Parallel threads
If the thermometer connecting head, neck tube, thermowell or process connection are
connected with parallel threads (e.g. G ½, M20 x 1.5 ...), these threads must be secured
using seals which prevent liquids from penetrating into the thermometer.
As standard, WIKA uses copper profile seals for the connection between the neck tube
and the thermowell, and flat paper seals for the connection of the connection head and the
extension neck or thermowell.
If the thermometer and the thermowell are already connected, the seals will already be
mounted. The plant operator must check whether the seals are suitable for the operating
conditions and must replace them, if necessary, with suitable seals.
For thermometers without a thermowell, and/or where these are delivered separately, the
seals are not included and must be ordered separately.
Tighten the threads by hand when carrying out the final assembly on the plant. This will
correspond to the delivery status of the premounted components. The final tightening torque
should be applied using a spanner (half rotation).
The seals must be replaced after dismantling!
The seals can be ordered from WIKA, indicating the WIKA order number and/or
the designation (see table).
6. Commissioning, operation