USER MANUAL DM9600
MRU GmbH, D-74172 Neckarsulm
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7.9.
Performing usability check (Option)
What is a usability check?
The usability check helps to determine and judge leakages (gas leakage)
in low pressure gas pipes.
Tested will be all in operation or repaired pipes with all faucets, however
without gas units and their regulators and security devices. The gas me-
ter can be included in this test (using backward test).
The usage capabilities test may not be performed when:
•
New installed pipes (= pipes within warranty)
•
Pipes that had a limited usage capability or a NO usage capability and
had been repaired to be used
•
Not in use pipes which want to be used again
•
Pipes in middle- and high-pressure range.
Test medium: Air or Methane
Test pressure: 23 mbar according to DVGW worksheet G600.
Unlimited usage capability: > 0 l/h to < 1,0 l/h
The pipe can be used for unlimited time without repair.
Limited usage capability: >1,0 l/h up to < 5,0 l/h
The pipe may be used for a maximum of 4 weeks. Within these 4 weeks
the pipe must be repaired to achieve Unlimited Usage Capacity again
(Leak-tight test).
NO usage capability: > 5,0 l/h
The use of this pipe must be stopped immediately. Take action to de-
termine the defect.
Important is the technical security judgment:
Also, a leak tight gas pipe can have limited or no usage capability. The
physical condition must be considered as well!
Once you smell gas the system is leaking. The above-mentioned usage
capability grading’s do not apply.
