Barry Cordage Blog

Break-strength vs. Overall Strength Rating: Why they are different ?

Written by Marc-André Pilon | 27-Apr-2022 10:15:00 AM

The breaking strength of a safety net system can be expressed in several ways: either by the breaking strength of a mesh, or by the lifting capacity of a mass. At Barry, we measure the breaking strength of the mesh. It is important to know that the breaking strength of the mesh alone does not give the overall capacity of the net system, and other factors must be considered.


Using the mesh break strength as a basis has many advantages, but also some limitations to consider. In a laboratory setting, it is possible to perform tensile strength tests during net manufacturing and residual strength tests on samples of nets in service.

Advantages:

  • Accurate results
  • Ideal for residual strength validation
  • Net systems installed in the field can be tested for residual strength using swatches

Limitations:

  • Destructive nature of the testing
  • Not representative of the overall strength of the net system

Note: No matter what type of data is known about a net, this data does not provide all the information about the capacity and safety factor of a net for a given use. In some cases, testing of the entire net system may be required to determine the ultimate strength of the system. In general, the strength of a system is greater than that of a single mesh, but the geometry of the net and the geometry of the mass it stops are crucial factors in determining this.

Important factors that will influence the capacity of a net include:

  • Angle of installation
  • Geometry of the net
  • The climate
  • The type of mass to be held or captured
  • Speed and geometry of masses
  • Level of tension
  • Number of attachment points

Barry's helicopter cargo nets are a good example of this nuance. They are designed so that the breaking strength of the entire net system is significantly higher than the breaking strength of the individual meshes of the net.

Finally, all Barry nets have corresponding technical data sheet which include the breaking strength of the net mesh. This information is useful for the net designer and should be supplemented by testing or analysis to define the capacity of the system as a whole.

The Barry team has 3 test labs for dynamic, static and electrical testing to help you arrive at the best safety net system possible. Contact us today if you need assistance, we're here to help.