In international sea freight, the 20GP and 40HQ containers are the two most commonly used types, but 90% of cargo owners are unaware of their true load capacity. A 40HQ container has 86% more volume than a 20GP, yet the shipping cost only increases by about 50%. This article reveals how you can optimize loading scientifically and add 15%-20% more cargo to each container using real data.
20GP Container: The Cost-Effective Choice for Small Shipments
Standard Parameters:
Internal Dimensions: 5.89m (length) × 2.35m (width) × 2.39m (height)
Door Frame Dimensions: 2.34m × 2.28m
Maximum Load: 28.2 tons (actual weight may be restricted by the route)
Loading Restrictions:
Any item over 2.3m in width requires special declaration (may not fit through the door frame).
Items over 2.2m in height require a frame container (standard containers can only bear 300kg/m² on the roof).
Light cargo with a density lower than 300kg/m³ is recommended to be loaded in a 40HQ.
Practical Case:
A furniture exporter optimized loading and managed to fit 12 more chairs in a 20GP container. By using the “pyramid stacking method” and utilizing the upper space, they disassembled chair legs and interspersed them with seat cushions. Airbags were used to fill any gaps to prevent damage during transport.
40HQ High-Cube Container: The Space Magician for High-Value Goods
Key Advantages:
An additional 0.3m in height (internal height of 2.69m) provides five extra standard pallet spaces.
Ideal for goods with a cubic-to-weight ratio of >1:500, such as clothing and electronics.
Maximum Load Formula:
(Overall cargo volume ÷ 54m³) × 100% ≤ 85% (reserved space for securing cargo)
Common Pitfalls:
Any cargo over 2.5m must be declared (some ports have crane height restrictions).
A single side weight over 10 tons can cause structural deformation of the container.
Classic Case:
An electronics company used the “3D Matrix Stacking Method” to layer monitors and CPUs, with anti-slip pads in between. They created a second platform using foldable internal supports, ultimately loading 2,100 laptops — 18% more than the industry average, providing a solution for the loading of special cargo.
Handling Irregular Loads:
Cylindrical Items: Use “honeycomb stacking” to increase space utilization by 5%-8%.
Irregularly Shaped Items: 3D scanning and modeling create the optimal loading plan (e.g., an auto parts supplier saved 23% in freight costs).
Temperature-Controlled Cargo Tips:
40HQ refrigerated containers must reserve 10cm of airflow space.
Temperature-sensitive goods should be placed away from the door and side walls (temperature differences can reach 7°C).
New regulations for 2024: These changes will affect your loading plan.
European and U.S. routes will mandate the use of smart locks (5cm reserved installation space required).
Some Southeast Asian ports impose surcharges on 40HQ containers carrying over 26 tons of cargo.
The Chinese customs are promoting the “3D Load Plan Pre-Approval” system; any discrepancies will result in fines.
