1. The cardboard drum should be round and free from obvious defects such as roundness, concavity, skewness, deformation, etc.

2. The barrel body is smooth without mechanical damage, wrinkles, or glue peeling. The waterproof paint is evenly applied without any omissions, bubbles, or obvious sagging.

3. Round rolled edges with smooth and paperless tongue.

4. The barrel hoop should be welded firmly and smoothly, without burning through or virtual welding, and without obvious rust, peeling, or cracking.

5. The closure is firmly connected and flexible to open, and the lid and bottom of the barrel are well sealed after closure.

6. Galvanized or painted barrel clamps and closures should be shiny and free from detachment.

7. When printing graphics on the barrel, they should be clear, uniform, firmly attached, and free of ink running.

8. The inside and outside of the paper bucket are clean and free of oil stains.