Why do we have to fill the air with wheels?

There are some inconveniences, annoying or even dangerous when a tire is deflated (or exploded). The outside of the tire is made of rubber, it is filled with air inside and it is just like a time bomb waiting to explode. Why don't we make tires entirely of rubber? Why do we fill the inside of the car with air?

According to Scienceabc, the short answer is: A pure rubber tire ( solid tire, no need to pump) has some disadvantages, including lack of shock absorption and very fast wear (still need replacement after one time use).

History of tires

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By 1868, the first rubber tire with hollow core was invented.

The history of tires does not last as long as the history of wheels in general (130 compared to 5,500 years old). For simplicity, we will focus on tire history and start with a solid rubber tire. When it comes to bicycles, they are usually made of iron on wooden wheels but in 1868, the first rubber tire with hollow core was invented. 20 years later, with the introduction of the first gasoline-powered automobile, the first pneumatic tire was invented by Benz (now known as the Mercedes-Benz brand). The first pneumatic tire is a metal wheel covered in rubber and filled with air. Before that, in wagons and other rudimentary vehicles, the wheels were made of metal. So this new invention changed all the play.

When synthetic rubber was invented in the early 20th century, it was used for tires more efficiently. And the invention of the patterns (grooves with different shapes on the tires) on the wheels increases the road friction coefficient, meaning that the wheels will grip the road more and the movement will be safer.

Wheels continue to grow with different types such as low pressure tires, tubeless tires and radial tires . Some types of tires can keep the car running even if it is punctured or supports more efficient braking. Now, we have new generation tires that are NPT tires - non-air tires , which are recyclable and user-friendly. However, why is the air-filled tire inside so popular during the past century? What are the benefits of air inside tires?

To search for a smooth ride: rubber combined with air

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Inflated rubber tires also help reduce friction.

When it comes to tire design, the most important factor is the ability of the air to be compressed and stretched easily , unlike something made of solid material. For example, when you are surfing on the road at a speed of about 96km / h, suddenly encountering obstacles such as a small rock or a hole in the road, immediately rubber tires will absorb and help the car pass with The smallest shock. Conversely, if it is a solid wheel (no air inside), you will be shocked, uneasy, even in an accident. Because the air inside helps the tires to continuously stretch to absorb the force, most drivers don't feel much with minor obstacles.

Besides, inflated rubber tires also help reduce friction. This is why rubber tires have been used in the past, before cars can run at high speeds on the road. When moving on flat roads, with few obstacles, rubber tires will be less damaged than when they are constantly obstructing obstacles with high friction. In fact, most people change tires not because of puncturing the tire but because it has been worn out over time so it no longer maintains the friction required for the road surface.

Meanwhile, with solid rubber tires (without internal air), production costs will be higher and make the overall vehicle heavier. In addition, this tire is less effective at reducing shock than air-pumped tires.

Now, there are a number of vehicles optimized by using specialized tires, for example: mountain bikes - low pressure tires, bicycle racing - high pressure tires. We understand why we need to pump air into the tires? But which pump is the most optimal?

Nitrogen gas pump tires

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Tires filled with nitrogen change less pressure due to the influence of temperature factors.

In recent years, tires are often filled with nitrogen gas, not normal air. Formula 1 cars have long used nitrogen in wheels for a number of reasons: nitrogen gas maintains stable tire pressure for longer than oxygen; Moreover, nitrogen-filled tires change the pressure less due to the temperature factor. Nitrogen tires inside tend to adjust to air temperature and humidity.

Nitrogen is "dry" and maintains a more consistent pressure in tires, regardless of where the race is organized or relative humidity on the day of the race. This provides more safety and stability than the case where tires are not pumped with nitrogen gas. Many car manufacturers have begun to supply rubber tires with nitrogen inside but the true value of nitrogen in this case has sometimes been exaggerated. The reason drivers, especially riders, want to pump nitrogen gas tires because they have the ability to move past speeds of 321 km / h so any slightest change in pressure or compression inside Tires can be dangerous, if not dangerous.

For the average driver, slight fluctuations in humidity and air pressure inside the tires are negligible.