Dungs FRM 100025 HD, Instruction Manual, Page: 161 / 174

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Edition 10.15 • No
. 270 442
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14.5 Leakage test
14.6 Recommended maintenance intervals
Max. inlet pressure [bar] Functional test Maintenance
> 0.1 to 1 every 4 years every 8 years
> 1 to 5 every 2 years every 4 years
> 5 once a year every 2 years
Lekspray
pmax = 10 bar
1
2
After maintenance or repair works, check the device for
internal and external leakages.
1. Test gases of the leakage test: air or inert gases.
2. Upstream and downstream shutoff valves must be closed.
3. Test pressure > blow-off pressure SBV: block the line
upstream of the SBV.
4. Connect the test section to the test device and apply pres -
sure.
5. Test pressure: 1.1 x system-specific operating pressure
Maximum PS of the device (SSD 100… 10 bar/SSD
60…6 bar). Different pressure ratings of the system must
be taken into account.
6. Observe the waiting time necessary for the pressure com -
pensation according to the system-specific volumes.
External leakage
7. Use a suitable leak detection spray on the device.
8. Monitor the foam formation.
Internal tightness
9. Remove the pressure in the test section downstream of
the device.
10. Monitor the increase in pressure on the outlet side: pres -
sure gauge accuracy 0.1 mbar
11. Once the leakage test has been carried out, open the
shutoff valve upstream of the SBV.
12. Release pressure in the test section.
13. Check the correct functioning and set values, see
section 11.3.
1. The maintenance intervals depend on the system-spe -
cific operating and environmental conditions, gas quality,
state of the pipelines, etc.
2. The maintenance intervals have to be set by the system
operator according to the system requirements.
3. It is recommended to perform a functional test on a
monthly base and carry out maintenance works every
year, in order to guarantee the system availability.
4. It is necessary to comply at least with the maintenance
intervals specified in G 495.