Leak Test; Calculation Of The Gas Pipe Volume - Dräger FG7000 Operating Instructions Manual

9.4 Leak test

Work on gas lines requires precise knowledge and adherence to the respective
standards and worksheets of your country-specific applicable legal regulations!
Gas pipeline installations, which are in operation, must be assessed by the degree
of their serviceability. The measurement of the existing leak rate in liters per hour
(amount of leakage measurement) is the basis for the assessment of serviceability.
Serviceability is divided into the following criteria:
Unlimited serviceability
Reduced serviceability
No serviceability
A semi-automatic serviceability test with air can be conducted with the FG7000 in accord-
ance with the German Technical and Scientific Association for Gas and Water (DVGW)
TRG1 2008 G600 Appendix 4 on gas lines with 23 mbar operating pressure.
To do so, the gas line to be tested must be closed off using valves and rinsed with air. After
determining the line volume and increasing the pressure in the line to 50 mbar, the pressure
in the line is measured for 1 minute after a stabilization phase. The amount of leakage for
natural gas is calculated from the measured changes in pressure, is displayed and can be
documented.

9.4.1 Calculation of the gas pipe volume

To calculate the volume of the piping system, the program has an input and calculation
function for the pipe table with up to 20 pipe sections and automatic total volume calculation.
Individual pipe sections can be entered with diameter and length or partial volumes or total
volumes.
Selectable cross sections are: ´Volume input´, 35 mm, 28 mm, 22 mm, 18 mm, 15 mm, 2",
1 ½", 1 ¼", 1", ¾" and ½".
A table with the individual pipe sections can be printed.
5695061
Edition 01 – April 2016
en
Operating Instructions Dräger FG7000
= amount of gas leakage < 1 l/h
= amount of gas leakage 1 l/h to < 5 l/h
= amount of gas leakage > 5 l/h
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