Oil seals play an important role in many machines and industrial equipment. Oil is commonly used as a lubricant. It reduces friction so that machinery parts can move more smoothly and with less resistance. Leaks, however, can result in the loss, which leaves machinery parts susceptible to damage and failure.
What Are Oil Seals?
Oil seals are ring-shaped mechanical seals that are designed to prevent the leakage of oil or other lubricants. Also known as lip seals and grease seals, they are commonly used around shafts and similar rotating or moving machinery parts.
Most machines with moving parts need lubricant to reduce friction. Lubricant, however, is only effective if it stays in place. Oil seals help to contain oil or other lubricants to the machinery parts with which they are used. They fit snugly around rotating shafts, thereby containing the oil. At the same time, oil seals also protect machinery parts from environmental contaminants like water, dirt, dust and debris.
How Oil Seals Work
Oil seals work by filling the space around the parts with which they are used. When placed around a shaft, for instance, the oil seal will form a barrier that contains the shaft’s oil while simultaneously preventing external environmental contaminants from entering the shaft.
When the shaft rotates, the oil seal’s lip follows the shaft’s surface, maintaining a dynamic seal. The garter spring ensures constant contact between the lip and the shaft, providing the necessary radial tension to create an effective seal. This design ensures that lubricants are retained, friction is reduced, and wear and tear are minimized.
Parts of an Oil Seal
They may look like ordinary O-rings consisting of a single piece of elastomeric material, but oil seals feature multiple parts. Oil seals typically feature a lip, case and spring.
The case is the part of an oil seal that holds it in place. The spring is a ring of energized material that provides radial tension. Finally, the lip is an outer rim or edge that serves as the primary sealing element. Once installed, the lip will sit directly on the surface of the shaft while the spring applies tension.
In Conclusion
Oil seals do a lot of heavy lifting to keep machines running smoothly. Their main job is to keep oil and other lubricants where it belongs. Additionally, oil seals keep out dirt, water and other junk from reaching machinery parts, which could otherwise result in damage.