Perhaps this morning you microwaved your breakfast while listening to a podcast on your laptop above the hum of your electric razor. Did you stop to ask yourself what these disparate machines all have in common? The answer is ball bearings. Ball bearings probably strike you as being particularly low-tech. Most people first encountered these clever devices while using roller skates or bicycles as a child and assumed that, once they were finished with riding toys, they would never encounter ball bearings again. In reality, virtually every device with moving parts—including analog wrist watches—uses ball bearings.
Why Ball Bearings Are Necessary
Simply put, ball bearings are tiny spheres encased in rotating metal tracks called races. Inside the bearing assembly, the weight of the wheel or whatever is turning—which is called the load—is evenly distributed. This eliminates most of the friction and allows for smooth, effortless motion. Ball bearings are engineered in a plethora of different ways to meet the needs of virtually every device with moving parts, no matter how high-tech it may seem. From wind turbine ball bearings that are five feet in diameter to the small stainless steel roller bearings inside the casters on your living room furniture, these clever creations make the world turn smoothly.
Rolling Into the Future
Ball bearings will continue to be a necessity for inventors and manufacturers as long as they devise machines with moving parts. The designs and materials used to construct bearings, however, change along with the needs met by these devices. The newest generation of small, sealed bearings uses ceramic balls or fluids.
Just as engineers know how many miles a car engine can last or how much water a dam can withstand, so they can predict how long ball bearings can rotate within a specific device. Most ball bearings intended for standard use in our homes and businesses will endure 1,000,000 rotations.…