The small can is very designed

2020-01-16 16:41

When you buy drinks in the supermarket, if you have both pop cans and glass bottles, which one do you prefer? Some young people will buy canned beer, sit on the side of the road to drink, and after drinking the cans, they can be used as ashtrays. Glass bottles are also worrying about breaking. But the can will explode. Jonathan Waldman says in his book rust: "a lot of people think that pop cans are more design conscious products in the world. Ordinary aluminum can is actually an incredible handicraft. Can is cheap, stackable, easy to transport and safe. Pop cans block sunlight and ultraviolet rays, which are better than glass and plastic. At the same time, pop cans are easier to cool than glass and plastic, and they are also good at isolating oxygen. ”

The first can box in the world was invented by the British in 1810. In order for the can to really pull, the notch on the lid must be made very fine, about a thousandth of an inch thick, and uncoated. The cutter is very sharp and powerful. In order to ensure that the scratches are just right, the factory uses cameras and pressure gauges for testing.

People all over the world consume 180 billion aluminum cans every year, equivalent to 24 drinks per person on earth every year. The United States and Canada account for more than half of that. One fifth of all American food comes from cans or cans. If you build up all the cans that are produced every year, about 13.5 million miles, that’s enough to build a can tower that leads to the moon, and another 55 can be copied. Of course, because an empty can can only withstand 250 pounds of pressure, and each can weighs half an ounce, you can only base 7353 at most, otherwise your own weight will collapse the bottom. So you can only build a 2757 foot can tower, 40 feet higher than the world’s tallest building.

We’ve probably bought bottled coke and beer. Beer is more suitable for filling. Beer is not only made for beer, but also for can. &Beer is not very corrosive. It has mild acidity and alkali. It can coexist with aluminum. The protein in beer consumes dissolved oxygen, thus avoiding corrosion of aluminum. Vitamin C in orange juice also consumes oxygen, which is why orange cans are produced very early. Sugar can absorb carbon dioxide, thus reducing the pressure inside the tank, so the performance of sugar free Cola is two grades lower than that of ordinary coke. For a particularly sour drink like lemon juice, a thicker coating is needed.

Drinks are like battery acid, rust is the number one killer of pop cans. What protects aluminum cans from corrosion is an invisible inner coating, abbreviated as IC. This plastic film must have high strength and elasticity, and its viscosity, stability and viscosity should be appropriate. This epoxy film is only a few microns thick, but without it, a can of coke can corrode through the tank in three days. It accounts for 0.5 cent of the cost of each can.

The problem is that about 80% of epoxy resins contain BPA (bisphenol A), which makes plastics plastic. &"The United States is still debating the uncertainty of the impact of BPA on human health, while Canada has included BPA in the list of toxic substances, France has banned the use of polycarbonate cups with BPA, and Japan has basically stopped using the coating of cans containing BPA. &In addition to pop cans, there are also a lot of opportunities to get in touch with BPA in modern society. The content of BPA in pop cans is very small, and even less of them infiltrate into drinks. Waldman, on the other hand, doesn’t buy canned goods anymore. He wrote: "I want to be a believer in pop cans, but I hope my children will not be exposed to endocrine infections because of my pursuit of convenience. ”

In addition to the pot to prevent rust, all metal products should be careful of rust. &Rust is the number one threat to the U.S. Navy, the stronger Navy on earth. In Ohio, cars usually lose ten pounds a year from rusting, which means that every night you can hear a sonata from half an ounce of metal. Corrosion is everywhere, which is why iron pots need to be coated with oil, why copper wires need to be protected, why light bulbs cannot be supplied with oxygen, why spark plug electrodes need to use metals such as yttrium, iridium, platinum or palladium, and why serious dental operations need to pay a high price. ”

Not only iron, but almost all metals are susceptible to corrosion. Corrosion usually results in visible marks: calcium turns white, copper turns green, scandium turns pink, strontium turns yellow, terbium turns brown, thallium turns blue, thorium turns gray and black. Rust has dyed Mars red, and on earth it has made the Grand Canyon, red brick and Mexican tiles the blood color. &Rust is a cruel enemy, never resting and constantly reminding us that metal, like us, cannot live forever. ”

About 10 million tons of deicing salt is used in the United States every year. Chlorine in the salt is as active as oxygen and more durable. In the United States, snowmelt salts have begun to react with steel in bridges, and chloride ions drill into them, like trillions of convulsions. Spraying deicing salt can make your radial tire roll normally on a snowy day, but it can also have a very bad effect on bridges in the United States.