WIKA TW61, Operating Instructions Manual

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WIKA operating instructions thermowell, model TW61
11593963.06 04/2019 EN/DE/FR/ES
13
EN
5. Commissioning, operation
Thermowells are delivered free from oil and grease (exception: carbon steels). Depending
on the application, the end user must check whether additional cleaning is required before
installation.
The thermowell must not be bent or altered in order to mount it. The fitting should be carried
out such that there can be no damage to the thermowell as a result of the plant operation or
the operator. If necessary, one of the thermowell/pipeline mountings mentioned below (e.g.
with pipe clamps) will be required. In particular, the neck should be secured by appropriate
methods against bending.
Version for orbital welding
In the orbital welding version, the TW61 is directly welded into the pipeline. Weld the
thermowell centered, without axial offset (without irregularities), orbitally in the pipeline. The
weld joint should therefore be made with appropriate care and in line with the applicable
and accredited welding procedures and tested. Likewise, the requirements of the pressure
equipment directive should be followed.
For general information on the design of a hygienic weld, we recommend the following
documents (among others):
■
EHEDG guideline 35 - Welding of stainless steel tubing in the food industry
■
EHEDG guideline 9 - Welding stainless steel to meet hygienic requirements
■
EHEDG guideline 8 - Hygienic Design principles, 6.3
Recommended installation for the angular housing design
Concerning the angular housing design it is recommended, to install the probe horizontally
and not vertically in the pipeline. Consequently the formation of an air pocket during
sterilisation in the cupola is avoided.
5. Commissioning, operation