20 liters of packaging barrels welded by automatic welding machine, 7 layer back sealing technology, can be pressurized to 20kPA, continuous 5 minutes will not leak, handle beam in the barrel body along the vertical direction of the load to 600N (about 60KG) 5 minutes after the barrel body connection parts without fracture without damage. Stacking 1250 N (125KG) Stacking time No leakage and deformation for 24 hours, and no leakage when dropped to the ground at 1.6 meters height