1. The basic structure of the steel drum: the bottom of the barrel, the barrel body, the top of the barrel, the closure (closed barrel closure and open barrel closure).
2. Development of steel drum structure:
• Structure and use of tapered steel drum;
• Structure, use and type of closure of open steel drum;
• Remaining steel drum structure: closure structure, barrel top structure.
• Structure and use of steel-plastic composite drums.
3. Steel drum coating: environmental protection requirements and development of water-based coatings, development of pre-coated coils, development of laminated sheets. 2. Coating in steel drum: compatibility and construction conditions of inner coating and internal cargo. 3, sealant: the choice of sealant, compatibility with the goods.