Strapping Products: Definitons

By |2018-01-30T07:58:42+00:00January 30th, 2018|Packaging Supplies|0 Comments

Common strapping terms that you need to know.

Strapping products come in several forms including steel, polyester, polypropylene, and cord.  Depending on the weight, size, and shape of your product, the strap best fit for your application may differ. It’s helpful to know the most common strapping terms, as these are key to making sure you understand your application while finding the best type of strapping to fit your needs.

You can learn more about the commonly used strapping terms below.

AAR Approved:  AAR stands for the American Association of Railroads.  AAR approved polyester strapping is made using the highest grade materials to ensure its quality.  It is tested and printed with an AAR approval number. For more information on the American Association of Railroads please visit their website at

Battery Operated Tools:  Battery Operated Tools, used with polypropylene or polyester strapping, combine tensioning, sealing, and cutting into one tool.

Break Strength: Break strength, expressed in pounds, refers to the amount of force required to break a strap.

Camber: The side-to-side curvature a strap. Machine grade strapping must be camber free to allow the material to move through the equipment.

Cord Strapping:  Manufactured from polyester fiber, one of the strongest synthetic fibers made. It is used in manual applications and sealed using buckles and metal seals or hand tied.

Color – The color of the strap is completely subjective and has no impact on the performance of the strap

Core Size Measurement:  The core size is the size of the paper tube the plastic strapping is wound on.  The first number in the measurement is the inside core diameter.  The second number indicates the width of the face of the coil.  It is important to match the core size of the strap to the dispenser or machine used for the application.

  • Hand grade polypropylene strap common core sizes:   16×6, 16×3 and 8×8.
  • Machine grade polypropylene strap common core sizes:  8×6, 8×8, 9×8 and 16×6.
  • Polyester strap, both machine and hand grade common core sizes:  16×6 and 16×3.

Double Notch Seal:  A strapping joint with two sets of notches.  A double notch seal is created with a double notched steel strapping sealer.

Creep: The reduction of strapping tension that occurs over time

Elongation: The % of stretch in a strap as force or tension is applied.

Elongation Recovery: The strap’s ability to return to its original state after tensioning.

Embossing: The textured diamond pattern applied to a strap surface.  Embossing helps to increase joint efficiency, reduce the risk of the strap slipping out of closure, and enhance split resistance.

Friction Seal: The method of sealing plastic strapping without a heated blade.  Instead, the seal is created by moving rapidly the two ends of the plastic strapping.

Hand Grade Strapping:  This type of strap is designed to be applied by hand with manual, electric or pneumatic tools.  It cannot be used in a semi-automatic or automatic strapping machine.

Joint Efficiency: The strength of a strap is only as good as the joints securing the two ends.  Joint efficiency is expressed as a % of the total breaking strength of the strap.

Knurling:  Knurling refers to the embossing found on the surface of polypropylene strap. The feed wheel in strapping equipment grips the embossed strapping to move it through the equipment.  Low knurling can thus cause misfeeds and/or strapping jams.

Feed Wheel Tensioner: Used to tension painted or waxed steel strapping on a flat surface.  This tensioner uses a serrated feed wheel to grip the strap.

Front-action Sealer:  Used for light duty strapping applications.  On the front-action sealer, the handles are held perpendicular to the strapping and pushed together to crimp the strapping seal.   

Manual Tools:  Manual tools require a tensioner, a sealer, and seals.

Polyester Strapping (PET: POLYETHYLENE TEREPHTHALATE): Polyester strapping is the most rigid strap, characterized by its high tension retention and low elongation.  PET strapping is characterized by the following features: Better retaining strength, lower weight, easy handling, weather resistant, and corrosion free.

Polypropylene Strapping: The most common and least expensive strapping material available. Polypropylene strapping is characterized by its high elongation and recovery, but low retained tension.  It is used in light duty bundling.

Pneumatic Tools:  Pneumatic tools, used with polypropylene, polyester, or steel strapping, combine tensioning, sealing, and cutting operations in one tool.

Push Type Tensioner:  The push type tensioner is used to tension painted or waxed steel strap on irregular or round bundles.  This tensioner uses a serrated feed wheel.

Rack-and-Pinion Tensioner:  The rack-and-pinion tensioner is used on round or irregular shaped packages.  It is used mainly with dry or lubricated steel strap.  

Shock Resistance: The ability of a strap to stretch and return to its original state upon impact without breaking.

Side-action Sealer: The side-action sealer is used in heavy-duty strapping applications.  Its lower handle can be laid on a flat surface so that the operator can apply more force on the strapping seal.

Split Resistance: The ability of a strap to resist tearing or splitting in the length.

Steel Strapping: Steel strapping is the strongest strapping material made.  It is characterized by its low elongation.

Thickness – The thickness is the physical thickness of the strap, measured in fractions of an inch, such as .020″

Tensile Strength:  Tensile strength refers to the stress at which a material breaks or permanently deforms.

Width – The width is the physical width of the strap, it must correspond to the tools or machine being used to apply the strap

Windlass Tensioner:  The windlass tensioner is used in heavy-duty applications.  It winds one end of pre-cut steel strapping around a slotted windless shaft.

Axis Packaging carries a full line of strapping, strapping tools, and strapping parts, along with a knowledgeable staff of specialists that can help you every step of the way. Strapping doesn’t have to be difficult, but it does need to be right, and that is where we come in.

Call today for more information at 1-877-410-5564 or let’s get a packaging assessment scheduled so we can talk.

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