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Stretch film itself has high flexibility, is not easily damaged, has strong impact resistance, tear resistance, tensile strength, and explosive resistance, so it can be used in many industries, especially in the packaging and logistics industries. Moreover, because of the strong stretchability of this film, it will have a very good use effect for both large and small items in packaging, and there are not many quality problems that occur during transportation. Now let's learn about its stretching methods.

1. Direct stretching is the process of stretching between the tray and the stretching film. This method has a low stretching ratio (about 15% to 20%). If the stretching ratio exceeds 55% to 60% and exceeds the original yield point of the film, the film width decreases, the puncture performance is also lost, and the film is easily broken. And at a 60% elongation rate, the tensile force is still very high, which may cause deformation of light goods.

2. Pre stretching is accomplished by two rollers. The two rollers for pre stretching are connected by a gear unit, and the stretching ratio can vary depending on the gear ratio. The tension is generated by the turntable. Due to the short distance of stretching and the high friction between the rollers and the stretching film, the film width does not shrink, and the original puncture performance of the film is also maintained. No stretching occurs during actual winding, reducing the risk of breakage caused by sharp edges or corners. This pre stretching can increase the stretching ratio to 110%.

3. The stretching mechanism of electric pre stretching is the same as that of roller pre stretching, except that the two rollers are driven by electricity and the stretching is independent of the rotation of the tray. So it has stronger adaptability, suitable for light, heavy, and irregular goods. Due to the low tension during packaging, this method has a pre stretching ratio of up to 300%, greatly saving materials and reducing costs. Suitable for film thickness of 15-24 μ m.

Not all stretching methods are suitable for the stretching film used at home. When choosing a stretching method, it should be based on the actual situation, such as checking whether the film itself can adapt to the stretching method and whether the use of the stretching method can bring benefits to oneself. When stretching the film, it is inevitable that some problems may occur. In response to this situation, relevant preventive measures need to be taken. Problems that can be prevented from happening should not be allowed to occur. Once problems, big or small, occur, they will damage the film itself.