Have you ever thought about why tennis balls are sealed? If you’ve ever played tennis, you know that after a while, the ball starts to lose its bounce. So, why are tennis balls sealed?
Tennis balls are sealed to ensure that the balls maintain the air inside. After manufacturing, tennis balls are stored for months and pressurized to keep the air pressure inside and outside the ball the same. In addition, because the air inside the ball escapes over time. Tennis balls are sealed so that they can retain their bounce for a longer period of time.
This guide will discuss the science behind tennis ball sealing and how it helps improve the game!
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Difference Between Pressurized And Non-Pressurized Tennis Balls
Pressurized tennis balls generally come with a fuzzy exterior and compressed air inside the rubber balls. The air inside the ball is what typically causes it to bounce. In contrast, pressureless tennis balls come with a solid interior and feature a fabric-like exterior.
Pressurized tennis balls help increase bounce and reduce weight. The International Tennis Federation (ITF) requires tennis balls to bounce between 53 and 58 inches (134.62 to 147.32 cm) at 69 degrees. You can make tennis balls bounce higher by removing the fluff.
Non-pressurized tennis balls typically have a firmer, thicker rubber core than pressurized balls, enabling them to bounce like the pressurized balls and mimicking some of their playing aspects.
After being manufactured, tennis balls may be stored for several weeks before being bought. They are stored in pressurized cans to ensure the balls preserve the air inside.
Tennis balls can preserve their bounce inside a pressurized can for years; however, you can’t keep your tennis balls indefinitely.
Here Is Why Tennis Balls Are Sealed
The main reason tennis balls are sold in sealed cans is to maintain their internal pressure. However, after you remove the balls from their cans, the clock starts ticking, and the balls begin slowly losing their interior air.
Knowing why tennis balls are sealed will help you save n the long run. The followings are the main reasons why tennis balls are sealed.
1- They Last Longer
Sealed tennis balls last longer and play better than those that are not sealed. The process of sealing a tennis ball helps to keep the pressurized gas inside the ball, which is what gives it its bounce.
Sealed balls also tend to have less dirt and grime on them, which can affect their performance. Ultimately, sealed tennis balls provide a consistent and reliable playing experience that can help improve your game.
2- They Are Less Likely To Go Flat
Sealed tennis balls are less likely to go flat, which means they bounce higher and play truer. They also last longer than non-sealed balls. Sealing the ball also keeps the internal pressure more consistent, leading to better performance.
There are various different and unique ways that manufacturers seal tennis balls. Still, most use a two-phase process that involves injecting a small amount of nitrogen gas into the ball before sealing it. This helps to preserve the internal pressure of the ball for a longer period of time.
3- The Seal Helps To Protect the Air Inside From Moisture
When a tennis ball is hit, the force of the impact transfers energy to the air molecules inside the ball, and they start to move around faster. This makes the air pressure inside the ball increase. The high pressure inside the ball pushes outwards on the rubber casing, and this is what makes the ball bounce.
If there was a hole in the ball, or if the casing was not sealed tightly, then some of the air would escape, and the pressure inside the ball would decrease. This would make the ball bounce less high.
The seal also helps to keep the air inside from getting too moist. When the air gets moist, it takes up more space than dry air, so the pressure inside the ball decreases. This would again make the ball bounce less high.
4- It Prevents Them from Going Bad
Tennis balls are sealed to prevent them from going bad. Without the seal, the balls would be exposed to air and moisture, which would cause them to deteriorate and become unplayable.
The seal also keeps the balls bouncing properly by maintaining the right amount of pressure inside. Not all tennis balls are sealed – some are designed to be played with immediately after purchase, while others may last for months or even years.
Choose the suitable, right type of ball for your needs, and you’ll be sure to enjoy many hours of play!
5- The Seal Helps Protect the Rubber Surface of the Ball
One of the primary functions of the seal on a tennis ball is to help protect the rubber surface of the ball. The seal helps to keep the air inside the ball, which in turn helps to keep the ball inflated and bouncy. If a tennis ball were not sealed, it would quickly lose air and become flat.
This would make the ball much less bouncy and much less fun to play with. In addition, the seal helps to keep dirt and other debris out of the ball, which can also impact its performance.
6- They Are Seals, So They Can Be Stored For a Long Time
Tennis balls are sealed so they can be stored for a long time without going bad. The air inside can prevent the ball from getting crushed and protect it from moisture and other environmental hazards.
Sealed cans of tennis balls can last for years without being opened, making them a great choice for long-term storage.
It is vital to note that once a can of tennis balls is opened, it should be used within some months, as the air will start to degrade the quality of the ball. Tennis balls that are not sealed in a can should be used within a week or two of opening.
7- Sealed Tennis Balls Can Be Shipped Around the World
One significant reason tennis balls are sealed is that they can be shipped worldwide. Sealing them keeps them fresh and prevents them from being damaged during transport. This ensures they will be in good condition when they reach their destination.
Another reason why tennis balls are sealed is to protect them from the environment. Sealing them helps to keep dust, dirt, and other debris from getting inside the ball and affecting its bounce. This also helps to extend the life of the ball.
Do Sealed Tennis Balls Cost More?
If you’ve ever wondered why tennis balls are always sealed in canisters or containers, they need to be kept under pressure to perform properly. Tennis balls are designed to have a specific amount of bounce, and this is only possible if they’re kept at the right pressure.
If the pressure gets too low, the ball will lose its bounce and won’t perform as well. That’s why sealed tennis balls usually cost a bit more than regular balls – because they’re designed to maintain their pressure and performance for longer.
To determine if your tennis ball is still good, hold the ball in your palm and squeeze, and if the ball gives quickly and you can pinch the sides together, therefore the ball is too flat.
Do Tennis Balls Go Flat If Unopened?
Tennis balls go bad because they are pressurized in a sealed can under pressure, keeping the balls at the designed pressure while waiting to be used. The pressure is released after opening the can; however, the balls, which are little porous rubber, will hold sufficient pressure for approximately a week to be used before they go flat.
If your can is significantly old, it will leak slowly and gradually, and you may find the balls flat when you open it.
Generally, the loss of pressure after opening makes tennis balls go bad. They might last about a week after you open them and can be stored for several years.
All tennis balls are sold in plastic cans with a metal pull top. You can squeeze the cans to verify that your new tennis balls have internal pressure.
How Long Do Sealed Tennis Balls Last?
Sealed tennis balls generally last about 2 years because the pressure in tennis balls’ can gradually leak out over time through micro leaks in the packaging. An unopened can of tennis balls will typically last about two years.
Remember that tennis balls are typically sold in cans or packs of three; each can or pack has a “use by” date stamped. Once opened, a can of tennis balls should be used within two weeks, and a pack of three tennis balls should be used within one month. Unopened cans or packs of tennis balls can last up to two years if stored properly.
Tennis balls are typically made of rubber, and the outer shell is covered with felt. The felt helps create spin and bounce, and it also protects the inner rubber from dirt and debris. Over time, the felt can break down, and the ball can become less bouncy. The rubber can also deteriorate, and the ball can become less resilient.
To extend and improve the life of your tennis balls, it’s important to store them properly. Unopened cans or packs of tennis balls should be stored in a cool, dry place. Once opened, the balls should be kept in a mesh bag or container and not exposed to direct sunlight or extreme heat. If you reside in a region with high humidity, keeping your balls in an airtight container with a tight-fitting lid is especially important to prevent them from soaking up moisture from the air.
Following these simple storage tips can help ensure that your tennis balls stay fresh and bouncy for as long as possible.
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Final Words
Tennis balls are sealed for various reasons, including extending their shelf life, protecting them from the environment, and shipping them worldwide.
Sealed tennis balls usually cost a bit more than regular balls, but they’re designed to maintain their pressure and performance for longer.