Integrity of 30B cylinder plug for physical contact

Compression test and helium leakage test were conducted using test specimens simulated a plug of 30B cylinder.This compression test was carried out for three angles (0°, 24° and 90° against the axial direction of the plug) until the plug threads failed, and leakage rate was measured. Test results showed that plug threads failed at 310 to 360 kN of load in 0° and 24° direction. However, in both cases, the leakage rate of the plug was maintained at 1×10-7 Pa?m3 /sec SLR or less even after the plug threads failed. Inthe case of load in 90° direction (i.e., load from side of plug), the leakage rate of the plug was maintained less than 1×10-9 Pa?m3 /sec SLR until 110 kN of load was imposed, but the plug threads failed and leakage occurred at 125 kN of load.In addition, a thermal evaluation was also conducted assuming that the plug was in contact with an overpack. This result showed that integrity of the plug could be maintained even if the plug was in contact with an overpack in the event of the thermal test under the accident conditions of transport.