H.EXTERNAL GAS LEAKAGE RECORDING TABLE APPENDIX B-70265EN/02
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Decision
Whether there is a leakage can be determined from the results of measurement as described below. If you
send your recording table via FAX to the FANUC service center, the service center will check if there is
a leakage.
(1) Leakage on the primary piping
Calculate the primary pressure variation rate according to the expression below to determine the
leakage state.
The unit of t1 and t2 is the hour.
C3 – C2 8
Primary pressure variation rate (%)=
C3
×
t2 – t1
× 100
If the calculated primary pressure variation rate is 5% or less, the presence of no leakage is
determined.
(2) Leakage on the secondary piping
Calculate the secondary pressure variation rate according to the expression below to determine the
leakage state.
The unit of t1 and t2 is the hour.
D1 – D2 8
Secondary pressure variation rate (%)=
D1
×
t2 – t1
× 100
The presence of no leakage is determined if the calculated primary pressure variation rate is
as follows:
- 10% or less when the piping is a polyfro (polyethylene) tube
- 6% or less when the piping is a stainless tube