Vahterus Plate - Recommended Periodical Inspections of Pshes; Cleaning the Heat Exchanger; General

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4.5 Recommended periodical inspections
of Plate & Shell heat exchangers
Fully welded heat exchangers:
After 5 years
¬ Internal inspection of shell chamber with endoscope
After 10 years
¬ Pressure test
Openable heat exchangers:
After 5 years
¬ Internal inspection of shell chamber with endoscope
After 10 years
¬ Pressure test
¬ Internal inspection by opening the unit
¬ Visual check of shell chamber and plate pack
Local requirements for pressure vessel inspections should also be followed. The in-
spection periods will be re-evaluated by the inspector after every inspection according
tothendings,andshortenedifnecessary.
5 Cleaning the heat exchanger
5.1 General
The rules and requirements for cleaning a heat exchanger vary from type to type. If
there is a risk of fouling, the unit’s performance should be monitored by measuring
temperature and pressure loss. When losses are greater than permitted, the heat ex-
changer should be cleaned.