Container Loading Operation Standards: Loading Sequence, Center of Gravity Control, and Securing & Lashing

Container loading is a technical task. With the same container and the same cargo, if loaded well, it can hold more, transport steadily, and reduce cargo damage; if loaded poorly, it may cause the container to tip over, cargo damage, or even safety accidents. This article systematically explains the core technical requirements of container loading operations.

Container loading topic series: before loading, first do pre-loading preparation and container inspection; for temperature-controlled cargo loading, pay attention to container temperature and humidity control; for fees on overdue container usage, see container usage fee and demurrage charge.

1. Pre-loading Preparations

1.1 Formulating the Loading Plan

The loading plan is the "blueprint" for container loading and should be completed at least 1 day before loading:

1.2 Tools and Materials Preparation

2. Basic Principles of Container Loading

The five basic principles of container loading are theunderlying rules for all loading operations:

The above five principles are all quoted from the Code of Practice for Cargo Stowage and Securing (CSS Code), the recommended standard for container loading operations by the International Maritime Organization (IMO).

Loading Sequence Explained

3.1 Standard Loading Sequence (Top View)

20GP Standard Loading Layout (Top View)
┌──────────────────────────────────────────┐
│  Row 1 →  Row 2 →  Row 3 →  Row 4 →  Row 5 │
│                                        │
│  ██████ ██████ ██████ ██████ ██████    │
│  █Heavy█ █Mixed█ █Mixed█ █Mixed█ █Light█    │
│  ██████ ██████ ██████ ██████ ██████    │
│                                        │
│  ██████ ██████ ██████ ██████ ██████    │
│  █Heavy█ █Mixed█ █Mixed█ █Mixed█ █Light█    │
│  ██████ ██████ ██████ ██████ ██████    │
└──────────────────────────────────────────┘
     ↑ Front (truck head)          ↑ Rear (container doors)
       Heavy cargo forward            Light cargo near door

3.2 Standard Loading Steps

Step 1: Start loading from the deepest point (front of container), arranging items in sequence along the container length
Step 2: Arrange each row neatly, leaving no gaps between rows
Step 3: After completing a row, separate it with an air bag to prevent forward and backward movement during transit
Step 4: Stagger layers in a brick-wall pattern to increase stability
Step 5: Load the outermost row up to the container door position and secure it firmly at the end

3.3 Loading Methods for Different Packaging

Center of Gravity Control

4.1 Three-Dimensional Center of Gravity Standard

                  ┌──────────┐
                  │  TOP     │
                  │    CG    │ ← Height: below 50% container height
                  │    ↓     │
   ───────────────┼──────────┼────── Fore-aft: 40%-60% container depth
   ←  Truck front │    CG    │ →  Container door
                  │          │
                  │  BOTTOM  │
                  └──────────┘
                  ←── Center line ──→ Left-right: within ±5% of centerline

4.2 Practical Center of Gravity Control Methods

Method 1: Uniform Weight Distribution Method

20GP Container Weight Distribution Diagram:
┌──────────────────────────────────┐
│  ████  ████  ████  ████  ██    │
│  █ 3t █  █ 2t █  █ 1t █  █ 1t █  ██    │
│  ████  ████  ████  ████  ██    │
│  ████  ████  ████  ████  ██    │
│  █ 3t █  █ 2t █  █ 2t █  █ 1t █  ██    │
│  ████  ████  ████  ████  ██    │
└──────────────────────────────────┘
 Total weight 18t  Truck head ← front 4 rows 12t → rear 1 row 6t → Container door
 Center of gravity position ≈ 40% container depth ← ✅ Pass

Method 2: Heavy Cargo Priority Method

Prohibitions:

• ❌ Strictly prohibited from stacking all heavy cargo on one side of the box — the risk of tipping over increases by 300% when turning.
• ❌ Strictly prohibited from concentrating more than 50% of the cargo weight at the tail of the box — cargo will impact the box door during sudden braking.
• ❌ Strictly prohibited from exceeding the rated bottom load of the box (usually 3-4 tons per wheelbase).

Gap Filling and Securing

5.1 Comparison of Common Securing Methods

The above reinforcement consumables are billed by piece/rod/strip/roll, and the price fluctuates with market conditions and procurement channels. The specific price is subject to the actual purchase price or the packing service quotation.

5.2 Usage Specifications for Inflatable Bags

Air bags are the most effective way to fill and secure cargo inside containers, but they must be used correctly:

Diagram of air bag placement:
┌──────────────────────────────────┐
│ █████ █████ █████ │ █████ █████ │
│ █cargo█ █cargo█ █cargo█ │ █cargo█ █cargo█ │
│ █heavy█ █heavy█ █heavy█ │ █light█ █light█ │
│ █████ █████ █████ │ █████ █████ │
│          ↑air bag    ↑air bag       │
│   Fill gaps between groups   Fill space between cargo and door │
└──────────────────────────────────┘

5.3 Lashing and Securing Standards

6. Container Loading Quality Checklist

After loading the container, confirm the following items one by one:

□ Goods are neatly arranged, no tilting
□ Center of gravity is within safe range
□ All gaps have been filled and secured
□ Lashing straps are tightened, edge protectors in place
□ Container doors open and close properly
□ Seal is locked, seal number recorded
□ Container number photographed and archived
□ Loading photos taken (before/during/after loading)
□ Loading list completed (including details of each row)

Regulatory Basis: Loading principles refer to the IMO Code of Practice for Cargo Stowage and Securing (CSS Code). Lashing and reinforcement standards refer to industry common operating practices.Data as of August 2026.

📖 Further Reading:

• International Shipping Operations Manual, Chapter 19: Trailer and Container Loading Operating Procedures — Step-by-Step Version (complementary to the technical standards in this article)
• Cargo Stowage and Securing — In-depth Interpretation of the CSS Code Regulations

Need a professional loading plan? Send your cargo information to Bofeng Logistics; we provide loading plan design + on-site supervision services.

Loading Service Consultation: 13075678958 | info@zhbfwl.com

Container Loading Frequently Asked Questions (FAQ)

Q: How to control the center of gravity when loading a container?

A: Place heavy cargo on the bottom layer and distribute it evenly to avoid one-sided loading; cargo with a high or offset center of gravity should have its loading plan adjusted or be secured with fastening devices, and checked against tally records after loading.

Q: How to handle gaps between the cargo and the container walls?

A: Use air bags, wooden blocks, cardboard, etc. to fill and secure, preventing movement and shifting during transport; choose filling materials and securing methods based on the cargo's weight, shape, and container type.

Disclaimer: This article is compiled and written by the Bofeng Logistics team, with content verified in August 2026. Container parameters and cost data may be adjusted due to changes in shipping companies, routes, and market conditions; please refer to the information confirmed at the time of booking.