As a ball sport, table tennis also has strict requirements. Table tennis is spherical, with a diameter of 40 mm, a weight between 2.53 and 2.70 grams, and a white or orange color. Let's take a look at table tennis. How is it made.
Configuration material
The material of the table tennis ball was originally made of a synthetic fiber plastic (nitrocellulose plastic), also called celluloid. From July 1, 2014, the new regulations began to use a new plastic ball with high molecular polymer as raw material .
in the material factory makes the raw material into a sheet with a diameter of 44 mm and a thickness of 0.8 mm.
Prepare a solution with 40% alcohol and 60% water, put the plastic sheet in it, and let it soften during the soaking process so that it can be uniformly formed.
After soaking the sheet, rinse the surface solution with clean water, and dry the surface moisture.
Molding
first need to use a metal mold to make a plastic sheet into a hemisphere, fix the sheet on the mold, and immerse it in hot water of more than 90 degrees while pressing.
After the sheet is soaked in solution and hot water, it will be more ductile. Pressurizing the mold will make the sheet slowly become hemispherical.
After the sheet is made into a hemispherical shape, it needs to be cooled quickly with water. After taking it out from the mold, one hemisphere of the table tennis ball is ready.
All burrs on the edge of the hemisphere should be cut clean by machine.
Detection and classification
To measure the thickness of each hemisphere, classify the hemispheres with different thicknesses, and the thickness difference between each group is only 0.01 mm.
Adhesion
After screening, each group of hemispheres with similar thicknesses is glued to each other, and one hemisphere is placed in a mold and heated to make the edge shrink and become smaller.
cover the reduced hemisphere with another hemisphere, and apply glue through the machine, and the glue will flow to the interface of the hemisphere with the gap.
Squeeze hard on the hemisphere through the machine, and the two hemispheres will be completely glued together to form a round ping pong ball.
Heat forming
Put a table tennis ball into a metal mold, there will be many small holes on the surface of the mold, put it into a 380-degree oven, let the air in the ball expand, so that the joints are more tightly attached, and the more smooth.
In order to clean the glue off the surface of the table tennis ball, make the joints smoother and achieve the required weight, the table tennis ball is put into the polishing machine for polishing.
Detects
by lighting to detect whether the seams are intact and even, and also weighs and rotates the table tennis balls, and grades them. High-quality ones are used for competitions, while low-quality ones are used for training.
Finally, print the brand and grade on the graded table tennis balls, so that the table tennis balls are ready.
To this day, table tennis is still one of the favorite sports of the Chinese people. It has become a kind of "ping-pong spirit" that wins glory for the country, strives hard, and keeps innovating, and it is still inspiring countless people.
