The best way to keep dirt out of a bearing is to use?

Using a seal is the most effective method for keeping dirt out of a bearing. Seals are designed to fit tightly around the shaft and bearing housing, creating a barrier that prevents contaminants, including dirt, dust, and moisture, from entering the bearing assembly. They are constructed from materials that resist wear and can withstand the operating conditions of the environment in which the bearings are used.

Seals not only protect against solid contaminants but also help retain lubrication within the bearing. This grease or oil aids in the smooth operation and longevity of mechanical components. By maintaining a clean environment inside the bearing, a seal plays a crucial role in reducing wear, extending the life of the bearing, and enhancing the overall performance of the machinery.

While caps, shields, and packing serve different purposes, they are not as effective as seals in creating a comprehensive defense against dirt infiltration. Caps might cover a bearing, but they do not always provide a tight fit. Shields can redirect some contaminants, but they may not adequately prevent dirt from entering. Packing, on the other hand, is often used to control leakage rather than specifically to block dust and dirt. Therefore, seals are clearly superior for maintaining the cleanliness and functionality of bearings.