Tag: woven strap

System Strength of Synthetic Cord Strap

Posted on by teamA-GG

When trying to determine the proper strength of synthetic cord strap needed in your load plan there are two types of measurements commonly referred to – Break Strength and System Strength – but what do these mean? Below are descriptions of each of these terms and why they are just some of the important terms to know when trying to decide which type of synthetic cord strap you need to secure your cargo.

Break Strength (also referred to as Tensile Strength):  The Break Strength of synthetic cord strap is the amount of force (commonly measured in pounds or dekanewtons) that a piece of strap can withstand before breaking and/or splitting. The Break Strength of strap is used to determine the strength of the synthetic cord strap alone, without the addition of a buckle (i.e. Joint Efficiency).

Joint Efficiency: Joint Efficiency is a percentage of the strap strength with the incorporation of a wire buckle or ladder buckle. The Joint Efficiency is critical when trying to calculate the System Strength.

System Strength: System Strength is the force (commonly measured in pounds or dekanewtons) required to break a unit of strap. This consists of one loop of strap and one buckle used to connect the ends of the strap, forming a “belt loop”. The System Strength can be found by multiplying two times the Break Strength of the strap by the Joint Efficiency of the buckle (Ex. System Strength = (Break Strength x 2) x Joint Efficiency).

Below is a diagram of the different types of measurements being tested.

When trying to obtain the proper System Strength of your strap, it is important that the same strap and compliant buckle combo are being used that was originally tested to achieve the AAR approval. Using an unapproved strap and buckle combination can lead to a different System Strength and cause your load to be non-compliant. The approved strap and their corresponding buckle can be found on the AAR’s website in Table 19.2 of the AAR’s Open Top Loading Rules. The list of AAR approved strap for doorway protection can be found in the AAR’s publication “Nonmetallic Strap Substitution for Steel Strap as Doorway Protection in Boxcars”.

Please note, not all the factors that need to be considered when choosing a strap for your load plan were mentioned in this blog. Understanding Break Strength, Joint Efficiency and System Strength will provide you with a good start on your search for your cargo strap. For more information about the strength of synthetic cord strapping and the corresponding buckles, speak to one of our knowledgeable technical sales and services representatives by calling us toll free at 866-858-8800.

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Woven Vs. Composite Strap – The Differences Between the Two

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Woven Vs. Composite Strap

Posted on by teamA-GG

Two of the most popular types of strap used in the cargo securement industry are polywoven and composite. Both are great products to use when securing your cargo, but there are differences between the two that make each one more suitable for certain load applications.

Polywoven strap is made up of polyester fibers that are woven together. Its strength comes from the way the fibers are woven in a multi-directional pattern, weaving both horizontally and vertically. The composition of polywoven strap allows it to have flexibility while providing good tension on rigid loads. The woven material provides slight elongation of the strap, helping it absorb some of the shock and impact during transit while still maintaining its position.

Composite strap is made up of strands of polyester fibers, all traveling vertically and coated together by clear polypropylene. The polypropylene coating increases its resistance to abrasion, yet still allows for slight elongation during transit. Due to its polypropylene coating, composite strap is much stiffer than polywoven strap. The stiffness of composite strap makes it easy to feed underneath pallets.

Both woven and composite strap have different wire buckles that are intended to be used with each type of strap. The difference is the finish on the buckles. For woven strap, you should use phosphate coated wire buckles. The phosphate coating on the buckle allows for more friction against the woven material. If composite strap were used with the phosphate coated wire buckles, the strap would become worn from the friction between the buckle and strap. Instead, for composite strap you should use galvanized wire buckles. The smooth finish of the galvanized buckle allows the composite strap to thread effortlessly on the buckle and stays in place because of the stiffness of the strap. If woven strap were used with the galvanized buckles, the strap could slip off the buckle as there would be no friction between the buckle and strap to hold the strap in place.

In order to get the maximum effectiveness from your cargo securement products, it is important the correct products are used together. To find out more about the products you should be using in your load plan contact us toll free at 866-858-8800.