All DYNAMICA SafeLift slings are made with Dyneema® and are manufactured according to DIN EN 1492-4. Every sling is custom-made with quality and safety in focus. The rope slings are constructed as a single, double or triple sling with a variety of options when it comes to covers and extra protection against abrasion.
What are DYNAMICA SafeLift rope slings?
DYNAMICA Safelift slings are rope slings made with Dyneema®, which is classified as the strongest fiber in the world. Dyneema® fibers are also known as Ultra-High Molecular Weight Polyethylene (UHMwPE) and are used for a wide range of different products where strength and flexibility are needed.
The same properties make Dyneema® fibers the best choice for heavy lifting slings. The low weight combined with strength makes SafeLift slings the perfect alternative for steel wire slings, traditional polyester slings or other types of lifting slings. The low weight makes the rope slings easy to handle but also safer to use, since the amount of stored energy in the sling is much lower compared with a steel wire sling.
DYNAMICA rope slings are mainly used for onshore and offshore lifting operations where for example wind turbine wings, turbine parts etc. are mounted, repaired or dismounted. All SafeLift rope slings are custom-made to provide our customers with the best possible lifting equipment for the specific lifting operations. Below you will find a few samples showing a double and a triple constructed rope sling with different cover options.
If you are more interested in fiber roundslings made with Dyneema you are welcome to read about our DYNAMICA SecureLift Fiber slings.
DYNAMICA Double SafeLift sling
Rope material : Dyneema® SK78
Eye cover material : Dyneema®
Diameter : 44 mm
WLL (SF: 7:1) : 90 t
Break load: : 630 t
DYNAMICA Triple SafeLift sling
Rope material : Dyneema® SK78
Eye cover material : Polyester
Cover, middle sling: Polyester
Diameter : 72 mm
WLL (SF: 7:1) : 320 t
Break load: : 2450 t
Cover and protection to prolong the lifetime of rope slings
To secure a long lifetime of your SafeLift ropes slings, it is often beneficial to apply a cover to protect the bearing points and to protect the sling body against abrasion in general. Dynamica Ropes offers different woven cover solutions as well as different types of braided cover solutions in case an extremely abrasion resistant cover is required.
See below a short description of woven cover solutions for rope slings.
- Heavy Duty Polyester : Orange Polyester cover
- Single Cordura : Blue Cordura cover with one layer
- Dual Cordura : Blue and red Cordura in “sandwich” configuration
- DuraForce : Light blue cover with a mix-cover
- Dyneema® 1,0 mm : White Dyneema® cover
- Dyneema® 1,5 mm : White Dyneema® cover
When choosing the protection for our rope slings bear in mind that:
“Dyneema® has a tenacity which is app 4 times higher than polyester and nylon. Dyneema ® is also highly cut resistant and more durable than other synthetic solutions”
All our SafeLift rope slings are custom made, and always well protected according to the standard, but it is optional wherever you wish to add an extra protective cover to your rope sling. Dynamica Ropes has an experience within manufacturing rope slings for a range of different industries, and we are always willing to guide you through our different cover types, in order to find the best solution for your lifting operation.
SafeLift rope slings (according to the EN-1492 regulations for safe use of slings) should be protected on the anchoring points as shackles, and lifting devices such as crane hooks. Rope slings should be protected from edges, friction and abrasion (EN 1492-1:2000+A1:2008 C.3.6), both from the load side and lifting devices such as crane hooks. The correct protection against damages of the rope sling caused by sharp edges and/or abrasion is a part of standard package from Dynamica Ropes. It can be a part of the rope sling, or supplied as a complementary product according to the sling design agreed with the customer. The sleeve protection must always be correctly positioned according to the planned lifting operation. For some lifting operations, it may be necessary to supplement this with additional protection.
Pay extra attention in cases where the rope sling might be in contact with very rough surface, sharp edge or have to be protected from a risk of friction. The correct cover used for a rope sling will prolong the lifetime of the SafeLift sling significantly. The cover protects the sling against abrasion, cutting and heat damage and can easily be replaced like in case of DualLock cover.
Dynamica Ropes offers sling inspection and recertification service for all Dynamica Ropes customers. It is our experience that rope slings, which have been handled and stored correctly, can often be repaired by replacing the old covers with new. The service agreement includes a professional quality check of DYNAMICA SafeLift slings, repairs of possible damages, proof load in our Test Bed according to the standard and recertification. Here is an inspection and retirement guideline by Dynamica Ropes, which you are welcome to download:
Understanding elongation process and effect – SafeLift rope slings
One of the most critical elements in the specification of any fiber is its measure of elongation: how much it stretches under varying degrees of load. There is so much to consider with the various forms of elongation in synthetic ropes
Elongation has different impact depending on the product type and application. In the following, we are explaining several types of elongation:
Elongation – “Reversible Elongation” of Dyneema® rope slings: Reversible Elongation also called Elastic Elongation is the stretch or extension of DYNAMICA SafeLift rope slings made with Dyneema®, which is immediately recoverable after the load applied on the sling is released. Most slings made with Dyneema® carry loads for only a short period. Elastic Elongation is fully reversible.
Elastic Elongation is a result of the elasticity of the fibers used in the construction of the sling: Dyneema® fibers has an extremely low elasticity compared with traditional fibers such as polyester or nylon. Each type of synthetic fiber has a different degree of elasticity.
Elastic Hysteresis – “Recover over Time”: Elastic Hysteresis means elongation, which is slowly recoverable. This is another form for elongation, which is recoverable over a period of time (hours or days depending on few factors) after the load has been released from the rope sling.
Splice Setting is Elongation caused by setting of the splice: The rope sling has an integrated splice connecting the rope into sling. The elongation of a spliced rope caused by the alignment of the fibers in the splice under tension. The sub strands and strands of the rope in the splice align when the rope sling is loaded. The elongation caused by splice setting can be removed by proof loading in the Test Bed. All rope slings made by Dynamica Ropes are Proof loaded in our 500 t Test Bed, or at the external supplier, if the Proof Load extends 500t.
Constructional Elongation of DYNAMICA SafeLift slings: Constructional Elongation is the elongation of a loaded rope sling that results in compacting of the rope construction and alignment of the fibers and strands in the rope. Constructional Elongation is reduced in the manufacturing process by running the rope through the intensive in-house heat-stretching system, which is applied on ropes used for manufacturing of rope slings. Rope slings are Proof Loaded in our 500 t Test Bed (or at the external supplier, if the Proof Load extends 500t) and the Constructional Elongation is removed from the sling.
Creep or “Permanent Elongation” is often not an issue: Creep is not really an issue for rope slings made with Dyneema® as most of the rope slings carry loads for only a short time. Dyneema® ropes will creep (elongate irreversibly) when being under a constant load over longer period of time which is done in an elevated temperature – and this type of use is not relevant for lifting applications.
The Effective Working Length tolerance for DYNAMICA rope slings (SafeLift)
Dynamica Ropes has an in-house Test Bed equipped with an extensometer that allows measuring the exact elongation of our rope slings made with Dyneema®. With this knowledge, Dynamica Ropes makes very precise EWL calculations on SafeLift slings, which mean that we are able to manufacture rope slings with a very low EWL (Effective Working Length) tolerance.
The Effective Working Length tolerance (EWL) of our SafeLift rope slings is always according to DIN EN 1492-4, which state an EWL tolerance of 3,0 %. Since we often deliver our rope sling solutions for engineered lifting, an EWL tolerance of maximum 1% is often agreed for a specific rope slings. All rope slings are proof loaded according to DNVGL-ST-N001 and delivered with a proof load certificate stating the EWL of the rope sling measured under tension.
How repeatable lifting operations influence on the elongation of DYNAMICA SafeLift rope slings
One of the functions built into our in-house Test Bed is the program letting us demonstrate how little elongation our rope slings have after being used time after time.
To clarify how the efficient work length of rope slings changes after several lifting operations, we have proof loaded a 52 mm DYNAMICA SafeLift rope sling to 50 t in total 50 times. The figure below illustrates the proof load procedure and the table highlight 6 of 50 cycles. The average elongation indicates that the elongation is smaller and smaller each time the SafeLift sling has been loaded.
|Load/cycle no.||Load||Min. elongation||Max. elongation||Average elongation|
|2||50 t||1031 mm||1060 mm||2,78 %|
|10||50 t||1046 mm||1061 mm||1,44 %|
|20||50 t||1047 mm||1061 mm||1,34 %|
|30||50 t||1048 mm||1061 mm||1,34 %|
|40||50 t||1048 mm||1062 mm||1,32 %|
|50||50 t||1048 mm||1062 mm||1,30 %|