The Differences Between Plastic and Steel Strapping
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Welcome to Packaging Incorporated’s Service Corner
My name is Jeff LaHay, and I’m the Senior Signode Service Technician at the Eden Prairie Service Center. I have been with Packaging Incorporated for 26+ years and started my career servicing Paslode pneumatic hand tools, and then went on to repair impulse cordless tools and now work in our Machine Services department. For the past ten years, I have been involved with servicing all Signode hand, pneumatic and battery/electric tools. I also repair/service our specialty nailers, staplers, and provide technical support for our automated machines. Below is an article I thought I would share that explains the differences between plastic and steel strapping.
The Introduction of Plastic Strapping
When plastic strapping was introduced, it was only natural that it was looked upon as a substitute for steel strapping. In one respect, it was – especially in those applications where steel had been used only because there was nothing available. Often, the steel was over specification in the first case. The existence of plastic strapping widens the range of strapping and offers new opportunities. But to take advantage of those opportunities, you have to know how it differs from steel.
The Key Difference Between Plastic and Steel Strap
With steel, elongation is not a key characteristic. It is a consideration with plastic strap, as long as you stay within its working range. A more important plastic strapping consideration is elongation recovery. Once tension has been applied and the strap has elongated, how hard will the strap try to return to its original length? With plastic, time changes the recovery. If you have a rigid load, polyester might be best. However, because it doesn’t elongate much, it doesn’t have room to recover. On a shrinking-type load, this can be a problem. Since both nylon and polypropylene elongate more than polyester, and have more room to recover, they would both be better choices. If a high level of retained tension is important, nylon would be the preferred choice and if retained tension is not important, polypropylene’s lower price may change the choice.
Understanding Tension and Recovery
The amount of recovery depends on the material, the amount of tension, and the amount of time held at that tension. If the tension is released immediately, plastic will recover a good deal of its elongation. But as time increases, the amount of recovery will diminish. Over time, tension will be lost, also. This is known as tension decay. Polyester exhibits the least amount of tension decay, nylon next, with polypropylene showing the largest amount of tension decay. Nylon and polyester work best when you need higher initial tension. Polypropylene is best when high initial tension is unimportant and only low retained tension is needed.
What’s right for you?
By now, it should be apparent that you should let the application choose the type of strapping. So the next time someone asks, “What’ll it be, steel or plastic?”, you’ll be in a position to select the strap that gives you the best possible total performance at the lowest possible cost for your application. If you need help, give us a call! We’d be more than happy to help you with all of your packaging needs, including strapping choices.
More Strapping Resources
Strapping Tools Guide: Steel vs. Polyester
Lock in Savings on Strapping by Making the Switch!
Learn how to Strap Safely with Our Strapping Safety Video
Steel Strapping Tools: Can Old Still Compete? An Infographic