5. Commissioning and operation
5.3 Tightening torques
Only ever screw in, or unscrew, the instrument via the spanner flats and to the
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prescribed torque using an appropriate tool.
The correct torque depends on the dimensions of the connection thread and the seal
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used (form/material).
NPT (tapered) threads are marked with "NPT" on the thread. Parallel threads do not
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have any marking.
Screwing or unscrewing the connection head is not permitted.
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When screwing in the instrument, please observe that the threads are not skewed.
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If M20 x 1.5 threads are loosened to the head with a counter nut, the IP degree of
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protection can no longer be guaranteed.
NPT threads to the head must not be loosened.
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A PTFE/PFA lubricant is applied at the NPT threads to the thermowell/protection
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tube. This must be renewed when the thread has been loosened.
Number of threads engaged according to the respective certification.
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WIKA operating instructions, models TR10-L, TC10-L, TR10-0, TC10-0 (Ex d)
Connection head, (1/4000, 7/8000, PIH)
Cable gland (metal)
Thread
1/2 NPT
3/4 NPT
M20 x 1.5
The connection between connection head and neck
tube must not be disconnected by the user.
The connection head may only be aligned via the
nipple-union-nipple threaded connection.
As-delivered condition: Hand-tightened (approx. 5 Nm)
After aligning the connection head, the connection
must be secured using 50 ... 60 Nm
Thread
1/2 NPT
3/4 NPT
G 1/2 B
G 3/4 B
M14 x 1.5
M18 x 1.5
M20 x 1.5
M27 x 2
Tightening torques
20 Nm
20 Nm
20 Nm
Tightening torques
30 Nm
40 Nm
35 Nm
40 Nm
27 Nm
35 Nm
37 Nm
41 Nm
EN
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