Plain bearings are known as mechanical components that are charged with bearing a load and allowing a rotational or sliding motion between the parts of the machine. The main purpose of plain bearing is to prevent the wear of points of support of the equipment that would take place if the shafts are rol

ling directly on the structure. These plain bearings contain two major parts. One of them is a fixed part that bears the load and is also known as the support of the plain bearing, whereas the other part is the area that gets worn out because it’s in contact with the moving element called bush.

Plain Bearings

Types of plain bearings

Plain or friction bearings

The moving and fixed surfaces have a sliding friction that’s separated by an oil film. These are also called solid bearings, bushes and friction bearings as they commonly have a cylindrical shape and consist of no moving parts.

Rolling bearings

In rolling bearings, the rolling surface and the journal of the shaft are the supports that are seperated with rolling elements so that when the bearing or the journal rotates, a rolling motion is generated easily instead of the sliding one. All of this is composed of the rolling rings that are equipped with rolling elements that are located between the shapes and depend on the use.

Self-lubricating bearings

These are self-lubricating plain bearings that have no external lubrication as they are manufactured with porous materials. So, when they are impregnated with oil, everything is slowly distributed and absorbed throughout the parts of the machine.

Hydrostatic bearings

The lubricant is basically used with an external pump in these bearings. The main demerit of these plain bearings is the failure in the supply of the lubricant that results in high cost and endangers the installation.

Hydrodynamic bearings

The best part about these bearings is that they don’t require external injection of the lubricant but if the bearing has moving parts that help in the generation of hydrodynamic effect, it will lubricate all the parts that are in contact with the bearing. All these bearings work on their own and don’t require a pressurized oil feed or an external support. These are used in machines that have a high torque.

Advantages and disadvantages of plain bearings


  • Plain bearings have lower costs.

  • They are lightweight.

  • You’ll have longer fatigue free service of these elements.

  • These are less noisy and require less radial space.

  • The installation is easy.

  • They have a great shock resistance.

  • They will allow you to go for higher rotational speeds.

  • With the self-lubrication bearings, the lubrication is not required at all.


  • Leads to higher friction especially during the startup or the transient process.

  • It requires more axial space.

  • The use of friction resistant material is indispensable.

  • It has a greater wear when you compare it to rolling bearings because of the direct friction between the shaft and the bush.

To briefly conclude, the rolling bearings perform similar functions to the plain bearings, however the selection of them depends on the type of project that’s required. So, whenever you’re buying the plain bearings, make sure that you go for the top-notch plain bearing suppliers.

Author's Bio: 

I am Eric Desuza a pro-level blogger with 5 years of experience in writing for multiple industries. I have extensive knowledge of Food, Fitness, Healthcare, business, fashion, and many other popular niches. I have post graduated in arts and have a keen interest in traveling.