Introduction
Most cargo that shifts inside a container was strapped. It was just strapped with the wrong width, the wrong buckle, or too few loops. Buyers often pick cord strap by price per roll and assume “polyester is strong.” The result is a lashing that looks fine at the factory gate and fails on the first heavy swell.
This guide gives you a clear break strength chart for cord strap from 13mm to 50mm, explains what those numbers actually mean, and shows you how to match a width to a load. It comes from 14 years of supplying strapping and lashing to exporters from Rajkot and Morbi. We cover the chart, a simple selection method, common mistakes, and quick FAQs.
What Break Strength Actually Means
Two numbers appear on every cord strap spec sheet. Mixing them up is the most common buying error.
Linear Break Strength (LBS)
This is the strength of the strap alone, pulled straight until it snaps. It tells you about the yarn, not your lashing.
System Break Strength (SBS)
This is the strength of a loop: strap plus buckle, tested as they are used. Because a loop has two legs passing through a buckle, SBS is usually higher than LBS. It is the figure that matters for planning.
Working Load
Neither number is your working load. A lashing should never be planned close to its break point. A common approach in cargo securing practice is to use about half of the system break strength as the usable capacity, often called the Maximum Securing Load (MSL).
Cord Strap Break Strength Chart (13mm–50mm)
The ranges below reflect typical industry values for polyester cord strap used with matching galvanised wire buckles. Exact figures vary by grade, so always confirm against the batch spec sheet.
| Width | Typical Linear Break Strength | Typical System Break Strength (with buckle) | Common Uses |
| 13mm | 230–350 kg | 380–500 kg | Cartons, light pallets, bundling |
| 16mm | 350–600 kg | 600–900 kg | Pallet unitising, drums, bags |
| 19mm | 450–750 kg | 750–1,000 kg | Heavy pallets, tile crates, light machinery |
| 25mm | 700–1,100 kg | 1,000–1,500 kg | Crates, steel bundles, container lashing |
| 32mm | 1,000–1,500 kg | 1,500–2,100 kg | Machinery, coils, heavy crates |
| 40mm | 1,300–1,800 kg | 2,000–2,700 kg | Heavy machinery, large coils |
| 50mm | 2,000 kg+ (woven lashing) | 3,000–4,000 kg | Very heavy units, project cargo |
A pattern worth noticing: going from 19mm to 25mm often adds more strength than going from 13mm to 19mm. Width gains are not linear, because heavier grades use denser yarn as well as more of it.
How to Choose the Right Width for Your Load
Step 1: Know the Force, Not Just the Weight
A 1,000 kg crate does not pull on its straps with 1,000 kg all the time. At sea, it is pushed forward, backward, and sideways. Cargo securing guidance uses forces such as:
- Around 0.8g sideways in rough sea areas
- Around 0.4g forward and backward in sea transport
- Vertical movement that reduces friction with the floor
So a 1,000 kg crate can need about 800 kg of sideways restraint, shared across your lashings.
Step 2: Divide by Your Lashing Count
Say you plan four lashings resisting sideways movement. Each needs to hold roughly 200 kg of working load. With a 2:1 safety approach, you want a system break strength of 400 kg or more per lashing. A 16mm system would cover it with margin.
Step 3: Match the Buckle to the Strap
A strong strap with an undersized buckle fails at the buckle. Use these pairings:
- Wire buckle width must match strap width
- Use heavy-duty buckles for 25mm and above
- Never mix a light-grade buckle with a heavy-grade strap to save cost
Step 4: Plan Your Tension
Cord strap holds best when pre-tensioned. Too loose and the cargo gains momentum before the strap takes load. Use a proper tensioner for 19mm and above. Hand-pulling a 32mm strap rarely reaches the tension it was designed for.
Quick Width Guide by Cargo Type
- Cartons on a pallet (under 500 kg): 13mm or 16mm
- Ceramic tiles and sanitaryware crates (500–1,200 kg): 19mm or 25mm
- Bagged goods and drums: 16mm–19mm, with more loops instead of wider strap
- Steel bundles and pipes: 25mm–32mm
- Machinery and coils (2–10 tonnes): 32mm–50mm, multiple lashings, often doubled
Here is a counterintuitive point. For irregular cargo, four 19mm loops often secure better than two 32mm loops. More loops spread the load, cut the risk of one failure, and grip uneven surfaces.
Common Mistakes When Reading a Chart
Treating Break Strength as Safe Load
If a chart says 1,000 kg and you plan 1,000 kg of load per strap, you have no margin. Plan at roughly half.
Ignoring the Buckle
Strap tests are done with a specific buckle. A cheaper, thinner-wire buckle can cut system strength sharply.
Forgetting Edges
A sharp steel edge can cut a strap under load well before it reaches its rated strength. Use edge protectors on steel, crates with metal corners, and coils.
Assuming All Cord Strap Is Equal
Two 25mm straps can differ by hundreds of kilos in break strength. The width is not the grade. Ask for the test figure.
Using One Long Strap for Everything
A single long strap across many packages lets each one move a little. Separate lashings per unit hold better.
How Strap Grade Affects the Numbers
Cord strap is made from high-tenacity polyester yarn, coated to protect the fibres and hold the shape. Within the same width, you will find light, medium, and heavy grades. Light grades suit domestic transport and stable cargo. Heavy grades suit sea freight, where loads move for weeks.
Elongation also matters. Good polyester cord strap stretches a little and recovers, which absorbs shock. Very low-cost strap often stretches more and does not recover, so tension drops mid-voyage.
A Worked Example: Tile Crate for Export
Take a Morbi tile crate weighing 1,100 kg, shipped in a 20ft container to the Gulf.
- Sideways force at 0.8g: about 880 kg
- Lengthwise force at 0.4g: about 440 kg
- Lashings planned: four sideways, two forward, two backward
Each sideways lashing must carry about 220 kg of working load. At a 2:1 margin, you need a system break strength of at least 440 kg per lashing. A 16mm system clears it, but most loaders pick 19mm for the extra margin against crate corners and uneven tension.
The lengthwise lashings carry similar loads. Add timber blocking at the front wall and the plan is complete.
FAQs
Which cord strap width is most commonly used for container lashing?
25mm and 32mm cover most container lashing for crates, machinery, and steel. 19mm is common for palletised goods. Very heavy single units move up to 40mm or 50mm woven lashing.
Is system break strength always higher than linear break strength?
In most cases, yes. A loop has two strap legs sharing the load through a buckle, so the tested system figure is usually higher. The buckle quality decides how much higher.
How many loops should I use on a pallet?
Most pallets need at least two loops in each direction. Heavy or tall pallets need more. Spread them evenly so no single loop carries most of the load.
Can I reuse cord strap?
Cord strap is generally designed for single use. Once stretched and cut, its strength can no longer be trusted. Buckles should also be replaced.
Do I need a tensioner for 13mm or 16mm strap?
For light cartons, hand tension may be enough. For anything going by sea or above a few hundred kilos, a tensioner gives consistent results.
Conclusion
The right cord strap is the one whose system strength, buckle, and loop count match the forces your cargo will face. Start with the force, divide by your lashings, and keep a 2:1 margin. If you are unsure which width fits your shipment, share your cargo weight and dimensions with us and get a recommendation before your next container is loaded.
About Amass Strapping Solution
Since 2012, Amass Strapping Solution in Shapar, Rajkot has manufactured cord polyester strapping, container lashing strips, wire buckles, and lashing tools for exporters across India. We supply matched strap-and-buckle systems in widths from 13mm upward, so your lashing performs the way the chart says it will.