Understanding “the three T’s”
Mooring fatigue lifetime is affected by a combination of the time under load, the tension level, and the operating temperature; factors we collectively refer to as “the three T’s.”
The relationship between these factors is non-linear, so it’s important for mooring rope users to understand their combined effect.
Get to grips with internal fatigue
Introducing the Dyneema® mooring lifetime tool, allowing you to quickly and easily view the effect of temperature and tension on rope fatigue.
Mooring ropes can be designed for maximum strength. However, factors such as increased tension during operations (e.g., when the rope is loaded more heavily to secure a vessel), mooring in mild versus severe conditions, and variations in ambient temperature can all significantly impact a rope’s internal fatigue.
This tool is designed to give you a visual understanding of a rope’s service life and demonstrate how the reliability buffer built into Dyneema SK78 fiber ropes ensures safer mooring operations.
Ready to try it out? Simply adjust the parameters below to fit your application and conditions – and gain clear insights into how the “Ts” affect the predicted point of failure for different fiber types.
Mooring fatigue lifetime visualizer
Mooring fatigue lifetime is affected by a combination of the Time under load, the Tension level and the Temperature. The 3T’s. It’s relationship is non-linear and its important for mooring rope users to understand the combined effect.
Mooring ropes can be designed for maximum strength, increasing the tension levels during operation, and vessels can be moored in benign or more severe conditions in lower or higher ambient temperatures.
This visualizer allows to see the effect on the reliability buffer that ropes made from Dyneema® SK78 provide, given a desired mooring rope lifetime. At Dyneema® we have detailed model available, based on DNV-qualified tension fatigue equations.
Note: Mooring lifetime visualization tool calculations are based on DNV-qualified equations.
Discover Dyneema® SK78 fiber in mooring lines
Learn moreThe Dyneema® difference
As you explore the modeling tool, you’ll notice a clear performance difference between generic HMPE fibers and Dyneema® SK78 fiber.
That’s because Dyneema® SK78 fiber has been molecularly engineered to deliver:
Although Dyneema® SK78 fiber consistently provides a reliability buffer far greater than other HMPE fibers, the size of that buffer at any given moment depends on the rope’s mooring history – including the tension, temperature, and time (“the three Ts”) that the rope has already experienced.
Discover Dyneema® SK78 fiber in mooring lines >> [link to mooring lines page]
Reliability in every fiber
As the world’s only backward-integrated manufacturer of UHMWPE, Dyneema® controls the entire production process from polymer to fiber. This unique capability means we can perform molecular engineering at the polymer stage and design to enhance properties like fatigue resistance. In turn, this translates into a larger reliability buffer in mooring lines.
Our commitment to reliability goes beyond manufacturing. We’ve developed comprehensive testing protocols and models – including our rope tension fatigue model, rope temperature model, and other advanced testing equipment that makes the invisible visible.
Explore our full suite of advanced modeling tools
Built using DNV-qualified equations, this interactive visualization tool offers an introduction to rope reliability modeling. But that’s just a glimpse of what we have to offer.
At Dyneema®, we’ve developed highly sophisticated modeling tools that can provide even more accurate, comprehensive, and detailed lifetime predictions, tailored to your operational conditions.
Get in touch to learn more about:
Advanced reliability modeling for your specific application
Comprehensive rope lifetime assessments
Dyneema® SK78 fiber specifications and availability
Technical support for your mooring line