GB/T 25986-2010Filling device of natural gas vehicles (English PDF)

5.2.8 Corrosion resistance

5.2.8.1 USE a 25× magnifier to inspect the components after conducting the corrosion resistance test according to the test methods specified in the Clause 6.10.1. There shall be no cracks on the components.

5.2.8.2 INSPECT the gas tightness of the filling devices after conducting the salt spray test according to the test methods specified in the Clause 6.10.2. The gas tightness shall meet the requirements specified in the Clause 5.2.2.

5.2.9 Vibration resistance

5.2.9.1 After the vibration resistance test is conducted to the filling devices according to the test methods specified in the Clause 6.11, the fasteners shall not be loose, and shall still be able to be turned on or off in the normal way.

5.2.9.2 The test shall be respectively conducted to the filling devices according to the test methods specified in the Clauses

6.4.1.1 and 6.4.2.1. The test results shall meet the requirements specified in the Clause 5.2.2.

6.1 Test conditions and instrument precision

6.1.1 Test conditions Unless otherwise specified, the conditions of test environment and the test medium shall meet the following requirements.

a) The temperature shall be within the range of 15°C to 35°C;

b) The relative humidity shall not be greater than 85%;

c) The atmospheric pressure shall be within the range of 86kPa to 106kPa;

d) The qualified liquid nitrogen and dry air conforming to the provisions specified in the GB/T 3864 shall be used as test medium.

6.1.2 Precision and range of test instruments Unless otherwise specified, the precision and range of instruments shall meet the following provisions.

a) Electrotechnical instruments. The precision shall not be lower than Level 1.0, and the range shall be 1.5 ~ 3 times the measured value;

b) Pressure instruments. The precision shall not be lower than Level 1.5, and PLACE the test pieces in room temperature. VENTILATE compressed air from the outlet end. Respectively HOLD the pressure at the locations where the pipeline pressure is 1.8MPa and 0.05MPa for 3min. CONDUCT the test afterwards.

6.4.1.2 Gas leakage test at high temperature PLACE the test pieces in the environment at 82°C. VENTILATE compressed air from the outlet end. Respectively HOLD the pressure at the locations where the pipeline pressure is 1.8MPa and 0.05MPa for 3min. CONDUCT the test afterwards.

6.4.1.3 Gas leakage test at low temperature PLACE the test pieces in the environment at -40°C. VENTILATE compressed air from the outlet end. Respectively HOLD the pressure at the locations where the pipeline pressure is 1.8MPa and 0.05MPa for 3min. CONDUCT the test afterwards.

6.4.2 Gas leakage test for reclaiming receptacles

6.4.2.1 Gas leakage test at room temperature PLACE the test pieces in room temperature. VENTILATE compressed air from the outlet end. Respectively HOLD the pressure at the locations where the pipeline pressure is 1.6MPa and 0.05MPa for 3min. CONDUCT the test afterwards.

6.4.2.2 Gas leakage test at high temperature PLACE the test pieces in the environment at 82°C. VENTILATE compressed air from the outlet end. Respectively HOLD the pressure at the locations where the pipeline pressure is 1.6MPa and 0.05MPa for 3min. CONDUCT the test afterwards.

6.4.2.3 Gas leakage test at low temperature PLACE the test pieces in the environment at -40°C. VENTILATE compressed air from the outlet end. Respectively HOLD the pressure at the locations where the pipeline pressure is 1.6MPa and 0.05MPa for 3min. CONDUCT the test afterwards.

6.5 Low-temperature leakage test

6.5.1 Low-temperature leakage test for filling receptacles VENTILATE liquid nitrogen into the test pieces for precooling. IMMERSE the SEPARATE the filling device from the reclaiming receptacle after the pressure comes up to 1.6MPa. The one-way valve shall close automatically, so as to keep the pressure in the reclaiming receptacle for no less than 2s. OPEN the outlet end afterwards to release the pressure to 0MPa. Repeatedly OPEN and CLOSE the one-way valve. The cycle frequency for opening and closing shall not be more than 5 times/min. The total number of cycle test shall be 1,000. OBSERVE the sealing condition whenever 200 cycle tests have been conducted. CONDUCT the gas leakage test at room temperature according to the provisions specified in the Clause 6.4.2.1. CONTINUE to conduct the test if there is no leakage.

6.7.2 Full-flow impact test The starting air supply pressure shall be 1.8MPa at the inlet of the filling receptacle. There are no restrictions on the outlet flow. The duration for each impact shall not be less than 2s. The air supply pressure shall not be lower than 1.3MPa at the end of the impact. RELEASE the pressure at the inlet afterwards to close the one-way valve. CONTINUE to conduct 30 impact tests. The starting air supply pressure shall be 1.8MPa at the inlet of the reclaiming receptacle. There are no restrictions on the outlet flow. The duration for each impact shall not be less than 2s. The air supply pressure shall not be lower than 1.3MPa at the end of the impact. RELEASE the pressure at the inlet afterwards to close the one-way valve. CONTINUE to conduct 30 impact tests.

6.8 Oxygen aging resistance test PLACE the non-metallic components of filling devices in contact with the natural gas in the oxygen at (70 ± 2) °C with the pressure of 2.0MPa for 96h.

6.9 Compatibility test IMMERSE the non-metallic test pieces of filling devices in contact with the natural gas in the natural gas at (23 ± 2) °C with the pressure of 1.8MPa for 70h. Rapidly REDUCE the pressure to 0 afterwards.