Which Rope Has the Greatest Tension?

wire rope rigging, Which Rope Has the Greatest Tension?

WHICH ROPE HAS THE GREATEST TENSION?

Which rope has the greatest tension? That’s a good question, with many answers that might surprise you. 

Rope tension can be a confusing concept for some to grasp (they’ve even studied why students have such a hard time grasping the concept of tension with a block and pulley)—we’re going to explain why ‘which rope has the greatest tension?’ isn’t necessarily the best question to ask.

Instead, we’re going to discuss how tension affects rope, and why different rope will demonstrate different tensions depending on the conditions. 

Rope tension is affected by a number of things. like the size/weight of the load, length of rope, diameter of the sheave, speed/velocity of the pull and any wear & tear the rope has been placed under. 

In this article, we’ll cover:

  • What’s rope tension, and why does it matter? 
  • Hoisting equipment selection
  • Tension fatigue—What is it? 
  • Tensile strength—What is it? 
  • Rope at Hercules SLR 

WHICH ROPE HAS THE GREATEST TENSION?

WHAT IS ROPE TENSION? 

Tension refers to what happens when a rope or cable is used to transmit a force. Put even simpler, rope is under tension when it’s attached to something. 

Consider what happens when a rope and hoist pulls a piece of building material. In this scenario, the rigger themselves isn’t in contact with the load, they’re not placing direct force on the load—The rope is. 

It’s a simple concept, with many ways to calculate, which all depend on different circumatances, like the weight the rope must lift and other factors that might impact tension. 

WHICH ROPE HAS THE GREATEST TENSION? 

There are many ways to discuss rope tension. Steel (iron combined with other mined materials) is considered to have one of the greatest tensile strengths. However, steel wire rope’s construction and fabrication can impact tensile strength, and its rated capacity.

This might seem a bit over-complicated, but it’s worth understanding how tension works, even if you’re not a physicist. Most mechanical applications use tension, which is calculated in newton’s. 

What’s a newton? A newton is the force you need to accelerate a 1-kilogram mass by 1-metre per second if no friction is present. However, this can change very quickly—that’s why for the sake of practicality, we won’t discuss what these calculations are, but how tension impacts a rigging operation. 

EQUIPMENT SELECTION & TENSION

Tension can help you understand rope’s breaking strength, as well. Breaking strength refers to the weakest point of the rigging (in this case, a rope) whether it be the webbing, end-fittings, or tensioning device.

A tensioning device is used to apply force at a particular point in the rigging to create tension. This is typically done to reduce hazards that would happen otherwise.  

TENSION FATIGUE

Tension fatigue happens to steel wire rope or synthetic rope when it’s subjected to different stress-levels (represented by the stress level exerted on the rope).

Basically, tension deteriorates with time and the older a rope is, the less accurate it’s original ratings become.

TENSILE STRENGTH

First of all—What’s tensile strength? Tensile strength (in this case) measures the force that would break the rope when under pressure. 

There are three kinds of tensile strength—They are:

1) Yield Strength

Yield strength refers to the highest amount of stress the rope can withstand without causing any deformations to the original rope dimension’s. 

2) Ultimate Strength

The ultimate tensile strength refers to the total amount of stress or force the rope can take.

3) Breaking Strength 

Breaking strength refers to a rope’s ability to withstand a lift, pull or move at a specific point. 

ROPE AT HERCULES SLR 

Although we didn’t necessarily tell you ‘which rope has the greatest tension’, we hope this helps you decide which rope to choose based on their tensile properties and what works best for the application, lift and load.

Hercules SLR carries rope for marine, safety, rescue, arborist applications and more—Drop us a line and we’ll pair you with the best rope for whatever application you have. 


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Hercules SLR is part of the Hercules Group of Companies. We have a unique portfolio of businesses nationally, with locations coast-to-coast. Hercules Group of Companies provides extensive coverage of products and services that support a variety of sectors across Canada which includes the energy, oil & gas, manufacturing, construction, aerospace, infrastructure, utilities, mining and marine industries. 

Hercules Group of Companies is comprised of: Hercules SLRHercules Machining & Millwright ServicesSpartan Industrial MarineStellar Industrial Sales and Wire Rope Atlantic.

We have the ability to provide any hoisting solution your business or project will need. Call us today for more information. 1-877-461-4876 or email info@herculesslr.com

Working Load Limit Vs. Breaking Strength

Working Load

When it comes to rigging like ratchet straps, winch straps, and just about any other type of strap in the industry, working load limit (WLL) and breaking strength are commonly used measuring metrics.

Every piece of load-bearing wire or rigging equipment carries its own working load limit and break strength rating. These numbers let the user know how much weight that piece of rigging is capable of securing. Though they are usually clearly stated, there is often some confusion about what the two terms mean.

Working Load Limit

WLL refers to the maximum allowed weight that a piece of rigging can handle under normal conditions. For instance, a winch strap with a WLL of 6,000 pounds should not be used to secure any load above that weight, as it exceeds what it is rated for. WLL is 1/3 of the breaking strength rating, therefore a strap with a WLL of 6,000 pounds would have a breaking strength of 18,000 pounds.

Break Strength

Break strength refers to the point at which any section of a given cargo strap or piece of rigging will f

ratchet-strap

ail. Break strength is determined by the weakest point of the rigging in question, whether it be the webbing, end fittings, or tensioning device.

For example, if a ratchet strap is made with end fittings, webbing, and a ratchet that are all rated for 10,000 pounds breaking strength, the overall strength of the product is 10,000 pounds. If any component of the ratchet strap has a lower breaking strength though, the break strength of the unit drops to the rating of the weakest component.

It is critical to understand the differences between the two figures and to make sure that any time you are securing a load, you do so with capable rigging. A failure could not only be costly, but dangerous as well.

Hercules SLR is part of the Hercules Group of Companies which offers a unique portfolio of businesses nationally with locations from coast to coast. Our companies provide an extensive coverage of products and services that support the success of a wide range of business sectors across Canada including the energy, oil & gas, manufacturing, construction, aerospace, infrastructure, utilities, oil and gas, mining and marine industries.

Hercules Group of Companies is comprised of: Hercules SLRHercules Machining & Millwright ServicesSpartan Industrial MarineStellar Industrial Sales and Wire Rope Atlantic.

We have the ability to provide any solution your business or project will need. Call us today for more information. 1-877-461-4876. Don’t forget to follow us on Twitter LinkedIn and Facebook for more news and upcoming events.