Generally, the craftsmanship of soccer ball is divided into hand sewing and machine sewing.
The hand-stitched ball is high-end, and each part of it is all handcrafted. Thanks to multi-layer high-strength lining reinforcement, thick wire and large pinholes, the ball is strong and resistant to kicking.
The machine-sewing ball is middle-to-low grade. Each part of it is sewn with a flat sewing machine and a high sewing machine. Finally, two sides are left to be sewn by hand. The thread is thin and the needle hole is small. The sewing thread can be seen from the appearance of the ball.
Fill the TPU soccer ball with proper air pressure first, then lift the ball so that the bottom of the ball is at a height of 1.8m, let go to make it fall freely to the ground, and watch the elasticity of the ball. The ball with a good elasticity can bounce to a height between 1.2m and 1.4m. The bounce height of poor quality balls is uncertain.
The standard stipulates the size of the circumference of various balls, and the circumference of a soccer ball should be 675 to 710 mm. A ball with an unqualified circumference value is not easy to control in use, and its trajectory will deviate too much.
The inspection method is to put the TPU soccer ball on the flat ground and make it roll forward and observe its trajectory. The rolling route of the ball that meets the standard is straight, while the rolling route of the ball that does not meet the standard will deviate a lot from the straight trajectory.
Another way to check is to let the ball do free fall several times and observe whether it is vertical when it bounces. If it deviates too much, it is a substandard ball.
The ball is required to have no air leakage, slow air leakage, etc. The commonly used inspection method is to fill the TPU soccer ball to a certain pressure and apply clear water to the air nozzle. If there are small bubbles, it means that the ball is leaking.
1. Look at the craftsmanship of TPU soccer ballGenerally, the craftsmanship of soccer ball is divided into hand sewing and machine sewing.The hand-stitched ball is high-end, and each part of it is all...
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