ISO 22548-2021 pdf free download – Ships and marine technology — Performance test procedures for LNG fuel gas supply systems (FGSS) for ships.
5Test procedure5.1Safety test
5.1.1 Test of e.g. alarm and safety devices
lt shall be confirmed that the alarm and safety devices,such as the ESD system, operation of valve(s).etc. are properly operative at ambient temperature and at the minimum working temperature.
The FGSs control system shall be connected and fully operative during the test.
5.1.2 Cryogenic function tests
The cryogenic function tests shall be carried out at the design temperature or lower before pressurizingthe FGSs to the design pressure.
The cryogenic function tests shall include following:
a)cryogenic mechanical operation test (e.g.valve operation, leakage verification, etc.);b)electrical integration test (control system) in cryogenic conditions.
5.1.3 ESD and blow down test
The normal operation of the ESD system shall be confirmed prior to the test set up.The test controlsystem shall be able to shut down the ESD valves in the test setup and safely depressurize the pipingsystem and return it to atmospheric pressure conditions by activating the blow down system. Thepiping system shall be pressurized with nitrogen prior to this test. This test shall confirm the testarrangement’s capability to shut down (ESD system) and depressurize the FGSs to atmosphericpressure (blow down system) in case of emergency.
5.2 Performance test
The performance test of the FGSs shall be conducted as per the following load steps (refer also toFigure 2). A test report shall be produced based on the data recorded properly (at least once every 5 s)during the test, see example in Annex A.
NOTE lf agreed with the client, the testing time at each step can be longer than specified below.
lf the FGSS has more than one supply pipe with different supply pressures, the performance of the FGSSshall be tested for each output separately. (See Figure B.2 in Annex B.)
a)Adjust the discharge pressure of the system to the test pressure.Record the minimum flow rate.b)Increase the flow rate to 25 %.Upon reaching step 25 % of the test flow rate, maintain the state for30 min. Record the measurement.
c)Increase the flow rate up to 50 %.Upon reaching step 50 % of the test flow rate, maintain the statefor 30 min. Record the measurement.
d) Increase the flow rate up to 75 %.Upon reaching step 75 % of the test flow rate, maintain the state for 30 min. Record the measurement.
e)Increase the flow rate up to 100 %.Upon reaching step 100 % of the test flow rate, maintain the state for 30 min. Record the measurement.
f)Decrease the flow rate down to 75 % of the test flow rate, maintain the state for 30 min.Record the measurement.
g) Decrease the flow rate down to 50 % of the test flow rate, maintain the state for 30 min. Record the measurement.
h) Decrease the flow rate down to 25 % of the test flow rate, maintain the state for 30 min. Record the measurement.
i) Decrease the flow rate down to the minimum test flow rate, maintain the state for 30 min. Record the measurement.ISO 22548 pdf download.