Choosing the right fiber for your mooring lines

The maritime industry is as dynamic as ever – and one of the key changes is the move away from steel ropes toward synthetic fiber ropes. This shift may be being driven by regulatory pressures, but many operators are quickly realizing that HMPE-based mooring and tow lines have clear advantages over traditional steel wire.

But here’s the thing: even in the world of HMPE, not all mooring ropes are created equal. For a truly superior solution, only ropes made with Dyneema® SK78 will do. That’s because our fiber has been carefully engineered to deliver a uniquely high level of performance over a longer service life.

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Dyneema® SK78 fiber: The number-one choice for mooring lines

Safety and efficiency are non-negotiable in modern shipping. Whether you’re mooring or towing a vessel, you know you need strength you can count on – but did you know there are other performance factors to consider when selecting the right fiber for mooring ropes?

At Dyneema®, we call these the FACTs: fatigue, abrasion, creep, and temperature. These are common failure mechanisms in mooring ropes – but Dyneema® SK78 fiber delivers the superior characteristics needed to overcome these issues, no matter how challenging the conditions.

And there’s more. With a lower carbon footprint than generic synthetic fibers and a bio-based version available, Dyneema® SK78 fiber helps protect not only crews and operations around the world, but also our planet itself. Plus, even in a fast-changing regulatory landscape, you can rest assured that our fiber is fully accredited by certifying bodies such as DNV, Bureau Veritas, and ClassNK, and that ropes are produced by our trusted partners in line with OCIMF MEG4.

Key performance criteria to keep in mind:

  • Fatigue

  • Abrasion resistance

  • Creep life

  • High and low temperature performance

Key ESG criteria to keep in mind:

  • Low environmental footprint

  • Quality, certification, and compliance

3x longer Fatigue life

Even once docked, ships are always in motion. That means the mooring lines used to secure vessels need to able to stand up to severe wear and stress, whether from the constantly changing line tension or the yarns rubbing against each other and other surfaces (like the fairlead).

Dyneema® SK78 fiber is engineered to offer at least three times the fatigue life of generic HMPE – at both fiber and rope level.

Not only have lines made with Dyneema® been stress-tested by our customers, partners, and external bodies, but we’ve also developed our very own, very accurate means of fatigue lifetime modeling. The model is based on a large amount of test data under a wide variety of conditions, and using it reduces the chance of failure and improves mooring safety.

Modeling parameters:

  • Minimum breaking load

  • Line construction

  • Duration of use

  • Metocean data

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4x better Abrasion resistance

Think abrasion is a fact of life in mooring lines? Think again. With jacketed and unjacketed ropes made using Dyneema® SK78 fiber, you can rely on excellent abrasion resistance – and all the durability and cost-efficiency benefits that brings. What’s more, in most applications, our proprietary coatings will further enhance a mooring line’s resistance to internal and external abrasion alike.

Dyneema® SK78 fiber is proven to give ropes up to four-times better abrasion resistance than lines made with generic HMPE.

Designing a mooring line for maximum durability against abrasion starts with the right fiber. Some generic synthetic fibers do well in hex-bar and yarn-on-yarn testing, but it’s important to remember these tests don’t reflect real-world rope performance. At Dyneema®, we invest significantly in developing equipment and methods to test both fibers and ropes in realistic conditions – including our dedicated Abrasion Test Machine – helping us to improve fibers and deliver the durability operators are looking for.

Testing parameters:

  • Performance in winching, lifting, and mooring

  • The impact of sharp angles

  • Fairlead rubbing

4x longer Creep life

The dreaded “creep” phenomenon: when the long molecular chains of HMPE fibers slide along each other, elongating the mooring rope and reducing its lifetime. But the HMPE manufacturing process relies on the agility of the polymer, which is also a factor in creep. The good news? With Dyneema® SK78 fiber, we’ve found a way to retain polymer flexibility during production while reducing creep during use – for ultra-low-creep fiber that makes mooring ropes safer for longer.

Dyneema® SK78 fiber is engineered to offer up to four times the creep life of generic HMPE – at both fiber and rope level.

Creep increases in higher ambient temperatures and with higher loads – so it’s critical to be able to accurately predict rope performance over time.

Thanks to our Creep Performance Tool, that’s no problem for Dyneema®. Developed by our experts over a multi-year research program, the tool means we can predict creep rate and elongation and estimate the creep lifetime of Dyneema® SK78 fiber applications.

Testing parameters:

  • Type of HMPE

  • Temperature

  • Time

  • Tension

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Performs at Temperatures from -40°C to 70°C

From the Arctic to the Middle East, mooring lines are relied on to perform in a wide range of ambient temperatures. On top of that, movement and tension in the lines generate heat from internal friction. How can operators be confident their HMPE mooring rope can stand up to extreme temperatures – especially at the higher end of the scale – no matter the task or the location?

Dyneema® SK78 fiber is engineered to withstand high and low temperatures from -40°C to 70°C.

As shown by our very own core rope temperature models, Dyneema® SK78 fiber performs safer at higher operating temperatures than generic HMPE, withstands temperature fluctuations, and is suitable for cryogenic temperatures. All this makes ropes containing Dyneema® SK78 fiber the most reliable choice the world over.

Proven performance:

  • No significant effect on break strength at 70°C

  • Moisture has no effect on stiffness or strength

  • Tested at -162°C with higher-than-rated break strength

Sustainability matters

The sustainability landscape can be hard for the shipping industry to navigate. So let’s keep it simple.

Dyneema® delivers the lowest carbon footprint per unit strength of all fibers.

As such, Dyneema® SK78 fiber is the ideal choice for more sustainable mooring lines – and the clear winner for operators looking to meet stringent sustainability goals.

Looking to take your environmental performance to the next level? You need our bio-based version of Dyneema® SK78 fiber: the world’s first-ever bio-based HMPE fiber, delivering a carbon footprint 90% lower than that of generic HMPE. Per tonne, bio-based Dyneema® fiber saves the same amount of CO2 as is emitted from charging 3.7 million smartphones. And for every 100 meters, mooring lines made with bio-based Dyneema® fiber save 1.8 tons of CO2 versus generic HMPE-based ropes.

The stats on sustainability:

  • Around 75% of the energy used to make Dyneema® fibers comes from renewable sources

  • Ropes made with Dyneema® fibers reduce the need for tugs during mooring, for a 20%-lower carbon footprint

  • Dyneema® fibers enable a longer rope service life and less material use over the lifetime of a vessel

  • Bio-based Dyneema® fiber emits 29 fewer tonnes of CO2 per tonne produced versus generic HMPE fibers

Contact our sales team

Want customized advice on choosing the right material for your mooring lines? Our experts are on hand with all the FACTs to help you strike the perfect balance between reliability and cost effectiveness.

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  • Unrivaled knowledge of the FACTs of rope performance
  • Tailor-made recommendations for your mooring assemblies
  • Expert understanding of mooring conditions at a wide range of berthing environments around the world
  • Support with lowering installation costs for mooring systems
  • Advice on regulatory compliance

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