Guo Yongpeng, founder of Pingpong.com, will answer you in detail: what is difference between seamless, seam and celluloid table tennis balls and what materials are they made of? What is three star standard?
Seamless table tennis balls are made of a new material, cellulose acetate, while table tennis balls with a seam are mainly made of new ABS materials, which are completely plastic.
Since 2014, ITTF has banned use of celluloid in table tennis balls because celluloid is a nitrocellulose material that will deflagrate. in case of fire, which is extremely dangerous and does not contribute to storage and transportation. In previous years, fires caused by celluloid table tennis balls have resulted in huge property and human losses. Therefore, in past, table tennis balls were not allowed on trains and planes, and they were prohibited items.
In addition, celluloid table tennis uses electro-expansion technology, injecting gas into a table tennis ball that can explode when exposed to open fire. In past, after table tennis ball was broken, you could smell smell of rotten eggs, because it was filled with this gas, which can fill and expand table tennis ball, making table tennis ball more round, because celluloid material easily deformed. If there is no gas filling, table tennis ball will be affected by temperature, and due to atmospheric pressure, edge of ball will be compressed inward, becoming out of round.
Seamed table tennis Widely used New material ABS plastic, ABS plastic is acrylonitrile (A), butadiene (B), styrene (C) three A terpolymer monomers with heat resistance, high hardness and high elasticity. It does not deform as easily under heat, and even if ignited with an open flame, it will not detonate, so it is safer and is also approved for boarding planes and trains. Thus, since 2014, more than 40 table tennis balls have been made from ABS plastic.
Seamless Table Tennis is made of acetate fiber material, which is closer in performance to previous celluloid, has good elasticity and good heat resistance. Compared with ABS, it is not as hard as ABS, but elasticity of acetate fiber material is better.
The difference between an ABS seamed ball and a seamless ball
1. The production process is different
Seamed ball is still same as previous celluloid production method: two semi-circular table tennis balls are made using a mold, and then two semi-circles are glued together with glue to form a round sphere. Lastly, toss ping pong ball into roller sander to smooth out edges of ball.
Seamless ball is to add cellulose acetate material into a round closed mold by double centrifugation technology, heat mold, and then rotate it at high speed so that material evenly enters inside of mold wall, and then cool while shaking to form a sphere without any gaps. The seamless ball was patented by patent inventor Zhang Huilun around 2015, and Pingpong.com also specifically interviewed him, so current seamless ball technology is in monopoly stage, and protection period for patented invention has not yet passed.
2. Various opt-out methods
Many golfers must feel that if they are used to playing balls with seams, they will be very uncomfortable if they suddenly switch to seamless balls. It's not really that ball isn't round at all, and it's not that it bounces unsteadily, but that you're used to playing balls with seams.
The bounce methods of seam balls and seamless balls are completely different. Below I will draw a picture. I exaggerated arc of ball after it landed on table so everyone can see it more clearly.
In above figure, it is easy to see that arc of rebound of seamless ball is higher, and arc with seam is lower. Of course, it's hard to measure difference in our actual test, but many professional athletes, including many golf enthusiasts, can also feel difference.
I've also asked many top athletes on national team what difference is between stitched and seamless, and their feelings were same. Small differences can have a huge impact on athletes Sealed balls are used in daily training, and even if they are all seamed balls, different brands of seamed balls will play differently. Not to mention seams and seamlessness. World competitions use stitch balls, but 729 seamless balls were used in 2017. At time, many athletes said that they were not used to it. They felt that speed and spin of stitch balls were not as strong, and ball felt a little floating. . This is due to non-adaptability caused by different jump arcs. Professional athletes have developed a ball-like muscle memory with sutures. Subtle differences will affect accuracy of judgments.
3. Amateur golfers feel difference between butt and solid game
Pingpong manufactures seamed and seamless table tennis balls. During this period, we met a lot of user feedback.
For example, if you used to play balls with seams, and suddenly switched to seamless balls, your first reaction is that balls are not round, not floating and difficult to hit. In fact, there is no difference in roundness, but he is used to waiting for ball to swing, now, when ball is on top, he naturally feels physically uncomfortable. It will take at least half a year to get used to ball nature of seamless ball, but after getting used to it, you will enjoy playing, as after arc of ball bounces higher, difficulty of returning ball is reduced, as well as rotation and speed of seamless ball. A little slower than balls with a seam, lovers golf course can play more rounds.
If you are used to playing with seamless balls, when you switch to seamless balls, you will feel that ball does not bounce well, too heavy and too heavy. In fact, weight of balls is almost same. It's just that arc of seamed ball needs to be pricked a little lower, so use a higher initial motion to deal with seamed ball and you will naturally feel that ball has poor elasticity.
In fact, there is practically no difference in elasticity of a ball with a seam and a seamless ball. We dropped a table tennis ball from a height of 30 cm to test rebound height of table tennis ball. a ball with a seam is almost same, so difference can only be a slight difference in rebound arc.
From 2021, difference between seamed and seamless balls is shrinking
The last paragraph talked about some differences in elasticawns of seamed and seamless balls, and this difference is now gradually decreasing, which could not but affect a major technological innovation in production process of seamed table tennis balls.Wide connection. seam technology upgraded to thin seam technology!
The reason why a seamless ball has a high bounce arc is because there are no gaps in it, and mass distribution of each point is almost same. There is a seam in middle of stitched ball, because two semicircles are glued together, so weight of seam is heavier than elsewhere, causing center of ball to shift. A seamless ball has no seams, so quality of each point is almost same.
Now seam ball uses a finer seam process, gap in seam is almost invisible, and difference in hardness and quality is also very small, so it is not much different from seamless ball.
Is there a seam with a center of gravity or a seamless center of gravity?
This statement is complete nonsense. According to current laws of physics of universe, what doesn't have a center of gravity? The pen also has a center of gravity.
Criteria for judging whether table tennis is good or not
One planet, two planets and three stars - rating criteria
The ranking of table tennis stars varies from low to high, mainly based on four measures of table tennis weight, eccentricity, hardness and roundness.
The following are various standards for table tennis parameters from one star to three stars in 2022. Pingpong.com provides most accurate data. What Jihu and Baidu know online is all nonsense! The following standards take precedence! Because Pingpong.com has invested in its own table tennis factory, and table tennis produced by Pingpong.com is now recognized as best quality in industry.
Planet: about 2.68-2.72 grams.
Second planet:2.72-2.75 grams
Three star ball: about 2.75-2.77g
Screening method. Use automatic scales for automatic screening and classification.
Special note. At present, weight of table tennis ball is mainly between 2.71 and 2.78 grams, and most of them are about 2.75 grams, which exceeds standard weight requirements of many three-star balls.
One planet:7-10 files
Second planet:4–7 files
Three stars:1-4 files
Three-star ball sifting method: Use eccentric machine to automatically sieve grade 1-4 table tennis balls, and then use eccentric machine to roll and screen grade 1-4 balls. This test method is to roll ball in middle of an inclined track. If ball goes straight, it means that ball is well rounded and there is no left-right deflection. If left-right deflection is large, it means that ball is not round enough. The roundness of a ball that can move in first gear is basically close to roundness of a perfect circle.
Special note: Currently, all practice balls with a one-star seam of ping pong net are eccentric between 1-4 gears, and 80% of balls are in 1-2 gears, you can say that it outperforms many three-star balls. The standard of ball, so roundness of single-ball mTable tennis balls are better than many brands of 3-star balls. Currently, there are no second star balls in table tennis factory. Our current production method is mainly to consider ball with best parameters as a three-star ball, and ball with second best parameters as a ball with one star (actually , 80% of them are also standard three-star balls), and rest of balls will be OEM for other users who do not have high requirements for table tennis, such as serving machine balls, or some OEM brands that only care about cheap balls.
Hardness and hardness tolerance
One Planet:top>0.9 mm
Second planet: top 0.81-0.9mm
Three star ball: top 0.7-0.81mm, waist 0.72-0.83mm, hardness tolerance ≤0.4mm
Screening method. Use hardness tester to measure all aspects of table tennis parameters. A ball with three stars must be rotated and tested more than 3-4 times. If it is within data range, it will be treated as three stars. If it cannot achieve this, it will be treated as one star or two stars.
Parameter description: top 0.81-0.9mm, waist 0.72-0.83mm refers to hardness tester needle of hardness tester when top or waist of table tennis ball is pressed , table tennis ball will have a range of extrusion deformation sizes, smaller value, harder ball, and needle cannot hold it.
Parameter description. Stiffness tolerance is difference between hardness of belt and hardness of upper. The smaller difference, more constant hardness of ball.
Special Note: At present, hardness parameters of one-star seam table tennis practice balls are mostly within range of three-star balls. And everyone who has used table tennis balls knows that it is basically impossible to pinch with two fingers, unlike some balls that break when squeezed with little force. The harder ball, higher hardness of table tennis ball.
The size of ball is between 40.05 and 40.30 mm, which corresponds to diameter of more than 40 table tennis balls
Two planets: top and bottom diameters - waist diameter over 0.05mm.
Three star ball: top and bottom diameters, left and right waist diameter ≤ 0.05mm.
Check method: Use roundness tester to check waist and top diameter of table tennis ball, subtract top and bottom diameters of top from waist diameter, and calculate error. range. Generally, it will be measured about 3 times. If there is an error, smaller range, better roundness of ball.
Special note. Currently, training balls with a one-star seam for table tennis nets have a roundness of 80% and are generally not inferior to balls with three stars.
Wet father: In fact, table tennis balls made with really good manufacturing techniques should be majority of balls that are close to standard of three-star balls. used and precision equipment should be in majority. The degree and quality of materials directly determine quality of balls produced. If batch of materials goes down and most of balls do not meet standard, then such a factory will not be close to closing. Therefore, basically more than 80% of balls produced by table tennis net factory meet standards of three-star balls. Our molds need to be replaced with a new set every two months to ensure accuracy and stability of balls.
The process of making a new table tennis material from darkest moment to beautiful twist
After International Table Tennis Federation banned production of celluloid table tennis in 2014, seam table tennis was still in a dark period of growth, looking for materials that could replace celluloid and provide good table tennis elasticity . Good roundness and strength. It was during this period that seam ball market collapsed completely, and professional athletes exaggerated to point that they broke a table tennis ball hitting the edge of a racket.
Manufacturers are very happy with this wrong method of table tennis. Previously, when a table tennis ball was flattened, it could still be scalded with boiling water. It's amazing, this table tennis collaborator can be passed down like a family heirloom.
Sorry, I just cut it into pieces while ironing, and I won't leave corpse for you. No matter which method you use, it will not work properly and will be disposed of immediately if it is broken.
The annual consumption of table tennis is actually very high, but because the previous table tennis was too durable, few table tennis factories were profitable, and this reform is nothing more than allowing some manufacturers to make money. It's normal to break a few times after playing badminton and consumers are used to it, but if a table tennis ball worth a few dollars breaks after playing for a few days, it will be a disaster.
So purpose of changing material this time is undoubtedly to allow consumers to change that mentality, as well as increase damage rate of table tennis, just like badminton. I believe that everyone has heard or experienced this kind of business incident. The iPhone company has already had an incident with a decrease in frequency. Previously, iPhone 6 worked very smoothly and did not freeze at all, but after system update, it began to freeze very much and program did not start Smooth. as Apple explains, is to extend battery life. Anyone with even slightest insight knows that industry calls this planned obsolescence. If it's not bad, you'll go broke. Otherwise, if you use a mobile phone, world will be destroyed and mobile phone company will close its doors if they sell mobile phone. It is said that Mi 6 still has a lot of nail users, and mobile phone is still very smooth.
Let's make a bold guess. Perhaps some table tennis manufacturers feel same way. After all, how much table tennis is consumed in world each year? Products that are bought repeatedly are products that can actually make money. No matter how expensive you sell a sole, it can last 5, 10, or even 20 years. No matter how cheap a table tennis ball is, if you break 10 balls every day, money will come in a steady stream.
But consumers don't buy it, don't take us table tennis users for fools, I can buy a table tennis ball for 6 yuan and play for a month, but I can't accept 1 yuan to buy a table. tennis ball and just play one game. Bad, not to mention table tennis is not cheap now.
So when seamless table tennis ball failed to solve durability problem of new materials, seamless ball was born. At that time, Yinhe and Xu Shao sent out seamless balls to clubs around world. My friends went to play, this time I don't know, I was shocked, seamless ball has been playing for several months, trademark is worn out, it is not broken, seam ball is broken all over ground, amateur golfers are thrown out immediately After receiving seam balls, we became one after another take seamless. The market for seam balls has declined linearly: between 2015 and 2017, share of seamless balls in amateur market even exceeded that of seam balls.
Even though only a few brands of stitch balls are intended for use due to professional competition. Although professional athletes complain that balls are easy to break, they still have to use suture balls for daily training. But at present, some well-known brands in table tennis market I can't sit still, good guy, if this continues, is that okay? If I don't make ball well, then my age-old foundation and brand reputation will be destroyed because of a small table tennis ball!
Therefore, since 2018, major seam ball manufacturers have been feverishly experimenting and improving technology of seamed balls, continuously improving strength and roundness of table tennis ball, bringing table tennis technology to an unprecedented level. In previous era of celluloid, ball was deflated, and while it could be scalded with boiling water, rebound of a scalded round ball would not be stable after all, so it could only be used for a wild ball or multiball. Good guy, now there are balls with a seam. After many years of crazy improvements, table tennis ball has been hit 50 or 60 times with side of racket without breaking or cracking, and roundness and rebound have also reached an unprecedented quality.
Seamless balls haven't improved much since 2018-2022. Due to some problems that are not comfortable to talk about here, some brands have abandoned seamless balls and started towalk on balls with a seam.
Word of mouth has slowly rebounded, with more and more users choosing these balls because biggest advantage of these balls is that they are cheap. In 2018, Double Happiness once tried to win a comeback to market Promotions, a box of 10 Samsung table tennis balls, are sold online at a price of early 20. This price is indeed a loss-making advertisement, and dealers are also following suit. Strategy really works Amateur golfers have also begun to regain confidence in seamed balls.
By 2022, domestic seamless ball market will account for more than 90%, and seamless ball market will shrink more and more.
So, consumer market works like this: users recognize product, not brand. Only when quality of product is really good and feedback from users is good, business can be done in long term. In this era, it's not just cutting leeks. Those who can get rich, whose products are competitive, will be able to own market.
November 05, 2023