8.1.2 Cleaning results
The cleaning result depends on the following factors:
●
T
emperatur
e
●
Time
●
Mechanics
●
Chemicals
●
Degree of soiling
These factors can be combined in such a way as to make an optimal cleaning result
probable.
8.2
Passivation
Before a system with long pipes and tanks is commissioned, it usually needs to be pas-
sivated.
Valve blocks are usually excepted from this.
Passivation is usually carried out with nitric acid (HNO
3
) at about 80 °C (176 °F) in a
concentration of 3 % and a contact time of 6 to 8 hours.
46 / 104 - 8.2 Passivation
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