1. Waterproofing and Sealing Requirements
1.1 Key Sealing Performance Criteria
Door Sealing System
Door seals are typically made of EPDM (ethylene propylene diene monomer) rubber gaskets.
Compression set ≤ 30% (tested at 70°C for 22 hours)
Door gap after closing ≤ 0.5 mm
After installation, the gasket should protrude 2 ± 0.5 mm above the sealing groove
Use of instant adhesives (e.g., cyanoacrylate) is strictly prohibited
Weatherproof Performance
Must pass ISO 1496-1 Test 13 (Weatherproofness), ensuring no water ingress under simulated severe marine transport conditions.
Continuous Sealing Design
All joints-including door frames, hinges, locking bars, vents, and drainage openings-must form continuous sealing surfaces to prevent rainwater and seawater ingress.
1.2 Sealing Test Methods (ISO 1496-1, Test 13)
Rain Simulation Test
Simulates heavy rainfall by spraying all sides and the roof of the container.
Requirement: No leakage.
Localized Water Pressure Test
Apply water pressure of 0.4 MPa to specific areas for 30 minutes.
Requirement: No leakage.
Field Inspection (IICL 5.1 Standard)
Use a spray gun at 0.3 MPa, positioned 0.5 m from the door seal, spraying for 30 seconds.
Requirement: No water ingress inside the container.
2. Durability Standards and Testing
2.1 Structural Durability
Roof Strength
Must withstand 1.5 times the rated stacking load (typically 192 kN)
No permanent deformation greater than 15 mm
No cracks or weld failures
Floor Strength
Must support a load of 7,260 kg without structural failure
Impact Resistance
Must withstand 600 J impact energy without cracking or permanent deformation
2.2 Corrosion Protection and Material Durability
Coating System (Marine Environment)
According to ISO 12944, coatings should meet C5-M classification (high marine corrosivity).
Three-coat system: primer + intermediate coat + topcoat
Total dry film thickness: 200–320 μm
Design service life: 15–25 years
Salt Spray Resistance
Neutral salt spray testing ≥ 1500 hours
Corrosion rating ≤ ISO 4628-3 Grade V3
Rust area ≤ 2%, no blistering
Flooring Materials
Wooden floors: moisture content and thickness swelling controlled per ISO 16537
Steel floors: coating system must meet C3-M or higher corrosion class
3. Practical Considerations for Manufacturing and Application
Manufacturing
Sealing gaskets must be compatible with base materials such as weathering steel or aluminum alloys
Must pass combined aging tests including salt spray, UV exposure, and thermal cycling to simulate real service conditions
Maintenance
Replacement of sealing gaskets must comply with IICL 5.1 inspection standards, ensuring continuous sealing integrity
Coating repairs must match the original corrosion protection class to avoid localized weak points
Inspection in International Trade & Logistics
Focus on verifying sealing integrity and coating condition during import/export inspections
Any leakage issues must be recorded in accordance with ISO 6346 container identification standards, ensuring clear traceability and responsibility allocation
