Helium Inspection Technical Requirements in EnglishThe introductions of heliun test for India BCPL natural gas cold box project1 OverviewAccording to requirements of article 19 in the technical docume

is 1X10-5 atm.cc/sec（1X10-9 Pa.m3/s）.

3. Equipment and Materials The following equipment and materials are required for the helium inspection test:

• Helium leak detector
• Nitrogen gas
• Helium gas
• High pressure hoses and fittings
• Pressure gauges
• Valves

4. Test Procedures 4.1 Inner Leakage Test 4.1.1 Connect the high pressure hose to the inlet of the exchanger and connect the other end to the helium leak detector. 4.1.2 Fill helium gas into the exchanger until a certain amount is reached, then fill nitrogen gas until the mixed gas pressure reaches the specified value. 4.1.3 Record the initial helium concentration and pressure, and start the leak detection. 4.1.4 If the leakage rate exceeds the qualified index, locate and repair the leakage point, then repeat the test until the leakage rate meets the qualified index.

4.2 Outer Leakage Test 4.2.1 Connect the high pressure hose to the outlet of the exchanger and connect the other end to the helium leak detector. 4.2.2 Fill helium gas into the exchanger until a certain amount is reached, then fill nitrogen gas until the mixed gas pressure reaches the specified value. 4.2.3 Record the initial helium concentration and pressure, and start the leak detection. 4.2.4 If the leakage rate exceeds the qualified index, locate and repair the leakage point, then repeat the test until the leakage rate meets the qualified index.

5. Conclusion The helium inspection test is a necessary procedure for the India BCPL natural gas cold box project. The test procedures and requirements must be strictly followed to ensure the quality of the heat exchanger