The durability of the zipper is the most important physical performance index that determines the usage range and durability of zippers. There are clear provisions on zipper strength in zipper standards of different countries around the world, which are also the basis for testing the quality of zippers. 

Zippers with varying specifications and types require different strengths to suit different purposes. Generally, zipper suppliers will provide a reference to the features and applications of zippers. The specifications and model number of the zippers must meet the usage requirements.

Methods for testing zipper strength are not limited, but the basic strength is usually determined by the following inspection methods. From these test results, the zipper strength suitable for the respective uses can be comprehensively evaluated.

Chain Cross Strength

It is one of the most basic strength indexes, called chain cross strength or tensile strength. It measures the zipper's ability to resist cross-stretching when the zipper is clamped.

Latch Lock Holding Force

The slider is self-locking in the middle of a zipper chain, and the zipper teeth are divided into left and right parts. Tense the left and right portions of the zipper teeth to assess the locking strength and resistance of the slider's internal components.

Cross Strength of Separation Unit

The zipper is locked and the two sides of the zipper release unit are fixed with the test clamp. Stretch the two sides of the zipper release unit to test its resistance to external force damage.

best stopping power

Lock the zipper and pull the slider up to its top stop. Pull the slider firmly with the tester to measure the top stop holding force.

Bottom stop Holding Force

Pull the slider all the way down to the bottom stop and fasten the two sides of the zipper with the clamps. Measure the bottom stop holding force and resistance of the slider's internal components.

Tab Tensile Strength

Fasten the bottom of the zipper and pull the slider to test the maximum force needed to lock the zipper

Slider Puller Tensile Strength

Pull the puller in a direction perpendicular to the bolt body until the puller and bolt body disengage.

E-zipper.com zipper is subject to most standards, including ASTM D2051-D2054, D2057-D2062 (US), BS3084 (UK), JIS3015 (Japan), QB/T2171-2173 (China), and BS3084 (UK). We always do various tests and strictly control zipper quality to meet customer's requirements.