Shaft seals, dirt seals, grease seals, lip seals, and many other names are only a few of the many names given to oil seals. They are simple components used in rotary shaft machinery to keep oil from leaking and impurities like dust, dirt, and water out. However, an oil seal’s most crucial role is to safeguard all ball, sleeve, and roller bearing types found in rotating shafts. Additionally, the seals stop blending two fluids that shouldn’t mix, such as water and oil.
A mechanical tool called an oil seal keeps lubricant from leaking out of the machine. It accomplishes its goal by sealing the equipment’s moving and stationary parts. Additionally, it prevents impurities from getting inside the machine and shortens its lifespan, an important role it completes.
Numerous oil seals exist, including PTFE lip oil seals, rubber fabric oil seals, and rotating V-seals.
An oil seal kit is a set of oil seals with the necessary dimensions and desired characteristics. An oil seal kit is more cost-effective and advantageous than buying individual oil seals.
Oil or other seals can be used for grease and oil seals. A flexible lip, radial lip, or rotating shaft seal are different names for an oil seal. Single lip, double lip, triple lip, and four or more lips are frequent configurations.
Double dust lip sealA seal with a garter spring design is the Double Dust Lip (DDL) seal. It has two dust lips, as the name would imply, plus a fluid lip with a garter spring to keep the lip firmly attached to the wear ring. Given the ongoing evolution of bearing seal designs, this seal would be considered a starting seal. For more than 50 years, this design has been the workhorse of the freight business; it still is in some regions. NBC Brenco Bearing Seal performs the fundamental task of keeping contaminants and grease out. Because of the garter spring, this seal would add the most torque and temperature to the bearing.
Efficiency plus bearing sealsDue to eliminating the fluid lip using poly inserts and rotors, the Efficiency Plus (EP) seal has a reduced torque value of fewer than 15 in-lbs. Although it features a triple dust lip rather than a double dust lip, the dust lip is still a molded component of the design. A labyrinth-like insert and rotor interlock each other to replace the fluid lip. NBC Brenco labyrinth provides excellent grease while lowering the torque required to rotate the seal.
Other types of oil seal and grease seals include:Single lip oil seal
Metal cased
All rubber or polymers
Internal orientation
External orientation
Axial orientation
Spring-energized
To serve as a physical barrier that keeps the lubricant in the designated area.
To stop the lubricating oil from leaking outside despite high oil pressure.
Act as a barrier to keep debris, contaminants, and other outside elements out of the system containing the lubricating oil.
Why are sealed bearings favored over the unsealed alternative? Why ought sealed ball bearings be preferred to unsealed ones? What advantages can sealed ball bearings offer?
Worry-free lubrication
No contact
Self-contained
Dynamic seals called bearing isolators are used to shield bearings from external impurities. They are revolving (rotor) and stationary (stator) elements. O-rings or strong seals are used in some bearing isolators, while they are constructed like labyrinths in others.
For many bearings, a good bearing seal is essential. Bearing seals perform a dual function by keeping lubricants from leaking out while preventing impurities from entering your parts. Both procedures can help your bearings last longer, but choosing the proper seals for your components is critical. Different types of bearing seals include:
Contact seals
No-contact seals
Labyrinth seals
.
Several variables, including maximum temperatures, required lubricants, available space, and more, may influence your choice of bearing seal. Each factor can affect the type of bearing best for your application, the amount of material required, and other factors.
Although the choice of seals is crucial to the effectiveness of your bearings, you don’t have to make that choice alone. Our experts at NBC bearings can collaborate with you to identify the bearings and bearing seals that provide the best, most affordable solution for your application, environment, and finished product.
As Gordon said the terms have lost meaning. Here is the old convention in the context of rotating shafts.
A grease seal is meant to hold back grease and would normally be low speed. This means no need for or possibility of a hydrodynamic seal. Not much consideration for wear either.
An oil seal is designed to hold back oil, must develop a hydrodynamic sealing surface and also compensate for runout and wear. To do this oil seals are more flexible and have a defined sealing lip that is spring loaded. Some have nternal features near the lip to push oil away from the lip to aid sealing but make them unidirectional.
So the convention may be lost but it shouldn’t be. There is a difference in design and function. Something like all bushings are bearings, but not all bearings are bushings.