Types of Bearings and Their Uses

Every machinery has some mechanical parts which are crucial for its appropriate function. Similarly, the role played by mechanical bearings cannot be disregarded. They do look small but their absence can disrupt the function of various processes in machines.

If you want to learn about bearings and the types of bearings, we have it covered in the guide below. So, let's take a look.

What are Bearings?

Bearings are used for improving the rotational movement of a shaft. They are meant to guide it and handle the process of load transferring from the shaft to the frame structure. Bearing is used in machines as a critical component and the rolling processes are highly dependent on it.

Why is Mechanical Bearing Important?

The surface leads to wear and tear when rotating metals come in contact with the other components. It impacts the durability and life of machinery and also impacts its operational efficiency.

Hence, the use of mechanical bearings helps avoid friction and improves smooth motion. These bearings are of small size in the shape of a ball and have a rolling motion.

Bearings reduce friction, improve operational efficiency, and reduce contact with the surface. They also help with handling loads and distributing them evenly.

5 Main Types of Bearings and Their Uses

There are 5 main types of bearings, which have subtypes, and each has a different use. The section below highlights in detail the uses of different types of bearings.

Type 1: Ball Bearing

Ball bearings are spherical balls that are present between the two bearings and they support axial as well as radial loads.

The holes have a component known as a retainer, which supports the balls and keeps them spaced uniformly. Such bearings are made using stainless steel 14401 or 4401 or roller bearing steel.

Deep Groove Ball Bearings

Deep-groove ball bearings consist of deep grooves in their outer and inner raceway, which hold these balls.

It has a simple design and is used in many applications like turbines, water pumps, and gearboxes. These bearings can handle loads and also support speedy rotations.

Angular Contact Ball Bearings

Angular contact ball bearings are meant to transfer force between the two rings, internal and external. Angular ball bearings can handle loads and work with high-speed operations.

Self-Aligning Ball Bearings

Self-aligning ball-bearing has a structure like a cage, which has two rows of balls having equal distance between the inner and outer race.

If there is any type of dynamic or static misalignment, the outer race adjusts the position of the bearing to correct it.

The major advantage of these self-aligning ball bearings is that they have the ability to self-correct their position. They absorb vibrations and shocks. It is used in machines where the chance of misalignment prevails.

Thrust Ball Bearings

The structure of these bearings has a cage that has two rings. The inner race is connected to the rotating shaft. There are two variations of single and double direction in thrust bearings.

In a double direction, the ball moves in an alternating pattern between the rings. These bearings can manage high-speed loads and are also very easy to install. They are mostly used in crane hooks and spindles of machine tools.

Miniature Bearings

Miniature bearings are small-sized ball bearings that are used in spaces that are small and require precise handling of load. The overall diameter of such bearings is less than 20 mm. These ball bearings are used in medical and electronic machines and even help reduce the noise when the machines work.

Thin Section Bearings

Thin section bearings consist of a layer of outer and inner race, which is thin enough to fit in a limited space.

The rolling part of these bearings can be in the form of cylindrical bars or balls. These bearings have very limited weight but ensure high accuracy. They are used in many applications that need high performance like electronics, aerospace, and defense.

Flanged Bearings

The flanged bearing has an extended flange, which is present on the outer race of the bearing. The flange offers to make the attachment strong for the bearing and frame. The flange also has a mounting setup.

These bearings are suitable for handling radial loads and are used in applications that have excessive vibrations.

Type 2: Roller Bearings

Roller bearings consist of different shapes of rollers which help in transmitting stress. The shape of these rollers is conical, cylindrical, or spherical. These rollers help increase the surface area to handle high loads.

These roller bearings support the radial or combined loads and improve the performance of moveable parts by reducing friction.

Cylindrical Roller Bearings

The cylindrical roller bearings have the ability to handle high radial loads as they have a linear contact between rings and rollers. They can support axial forces of moderate levels and are used in drilling rigs or tool spindles.

Spherical Roller Bearings

Spherical roller bearings have spherical rollers in the form of a cage– two rows that are separated. These bearings can roll to reduce friction and also support larger loads from the shafts.

The spherical roller bearings can self-adjust the misalignment of the outer ring of the shaft. These bearings are used in marine propulsion and off-road cars.

Tapered Roller Bearings

Tapered roller bearings have a tapered inner, which is called a cone and an outer, known as a cup, consisting of tapered rollers having a cage between them. The tapered angle of the outer ring has a range between 10 to 30 degrees.

The tapered shape can distribute the axial load of the shaft, which is heavy, and also accommodates the radial loads. They have a compact design, which makes them suitable for limited space. These bearings are used in mining and railway systems.

Needle Roller Bearings

Needle roller bearings are the same as cylindrical ones, but the size differs. The needle roller bearings have a diameter of less than 6mm, and they are also known as low-weight and high-speed roller bearings.

They are suitable for compact spaces and support high radial loads. They are used in applications like piston pin bearings.

Thrust Roller Bearings

Thrust roller bearings consist of a structure the same as thrust ball bearings. It has a length spherical roller rather than a ball, and it can handle heavy axle loads that have no direction.

These bearings are used in heavy duty industries for compressors and turbines.

Cross Roller Bearings

Cross roller bearings have a cross pattern of rollers in cylindrical shape. It has alternative rollers which interact with each other at a right angle.

The arrangement of rollers supports the precision and rigidity in handling radial stresses and axial stresses. These rollers are highly suitable for controlling motion.

Type 3: Plain Bearings

Plain bearings are simple types of bearings and they do not have any rolling elements. They consist of a cylindrical bore which holds the components like shafts.

These bearings are also called bushes or sleeves. They have a plain surface, which states the load is heavy and helps lower friction.

Plain bearings have multiple configurations like washer, flanged, cylindrical, sliding and thrust. They have features like tabs, notches, holes, and grooves that come in contact with the surface and help in reducing friction.

The plain bearings are opted in operations composed of low speed and heavy load where the chances of oscillation and misalignment prevail. Their applications are observed in agriculture machinery and cranes.

Type 4: Fluid Bearings

Fluid bearing tends to replace the metallic bearings using a fluid layer, it can also be composed of gas, air, and lubricant between the rotor and housing surface.

Fluid bearings are applied to moving parts that are not in contact with one another. The fluid helps to hold the load and ensure smooth movement between components. The two types of fluid bearings are as follows:

Hydrostatic Bearings

Hydrostatic bearings work using a pressurized fluid; the fluid is injected between the parts that move under high pressure. It helps in reducing the friction and maintains the movement. The external pressure here helps maintain operation.

These bearings are opted for linear and rotary motion. They are used in gas turbines and spindles of machines.

Hydrodynamic Bearings

Hydrodynamic bearings are bearings in which low friction and load support are provided. They have a fluid that helps to create a bearing film with the help of motion between the contact surface and the journal.

These bearings depend on the speed of rotation, alignment, and viscosity of fluid. They are suitable for turbines and other applications operating at high speed.

Type 5: Magnetic Bearings

Magnetic bearings use electromagnetic force, which helps in suspending and rotating the rotor in a given position. The electromagnetic field is present inside the bearing composed of wires on a ferrous material.

As soon as the magnetic field activates, the force is applied to the rotor component, which makes the magnetic bearing operate at high load and speed.

Active Magnetic Bearings

An active magnetic bearing controls the position of the rotating shaft with its control system. The control mechanisms and integrated sensors process the real-time data, and the position is adjusted by the control unit.

The self-position and real-time monitoring of this bearing help with precision in steam and motion control. These bearings are used in applications like flywheels, turbochargers, and machine tools.

Passive Magnetic Bearing

Passive magnetic bearings have no feedback or active mechanism which adjusts motion. Rather, it has a permanent magnet, which is aligned in a way that makes the attractive and repulsive force to control the rotation and position.

These bearings need less maintenance and are very affordable. They have a simple design and work with noise.

Benefits of Using Bearings

Bearings have many benefits, and some of these are as follows:

• Bearings can reduce the vibration levels and noise.
• Bearings have the ability to handle axial as well as radial loads at the same time which helps to increase load capacity and reliability.
• They can offer simple lubrication and offer corrosion resistance when made using plastic.
• Bearings ensure that the applications feature low maintenance and they themselves have a low cost of maintenance.
• The bearing can handle heavy radicals at a higher speed.

How to Choose Different Types of Bearings?

The different types of bearings can be chosen considering some factors, and some of these are as follows:

Load

The load handling capacity of the bearing plays a vital role as it involves combined axial and radial movements. The load-bearing capacity of the application and the bearing must match.

Rotating Speed

Every type of bearing does not support a rotor or high-speed shaft. Bearings like deep grooves and rollers operate at high rotation speed. Hence, the type of bearing must match with the rotating speed.

Accuracy

You need to identify the allowable solutions for your application and then select the bearing with relevant rotational accuracy. Some applications like electronics and aircraft may need high accuracy.

Rigidity

Bearing rigidity is an important factor in some machineries. Like in the tool spindle of a machine, the bearing rigidity is crucial, and it may need tapered or roller bearings.

There are different types of bearings that can be preloaded so that the rigidity can be increased, like angular and tapered roller bearings.

Other

When the space is limited in the radial, you can choose a needle roller bearing. The vibration and noise requirements are also considerable, and in this case, groove or deep ball bearings are suitable.

Material Selection of Bearings

There are different types of materials that can be opted for when it comes to manufacturing bearings, and some of these are as follows:

Carbon Steel: Carbon steel is known for its durability and strength, offering affordability. It has the ability to handle limited pressure but cannot be used in environments that are highly corrosive.

Chrome Steel: Chrome steel is a type of material that offers high hardness and resists wear. It has the ability to maintain its shape when subjected to high stress and is used in precision bearings.

Stainless Steel: Stainless steel bearings are suitable in such applications which are prone to corrosion and moisture. This material offers a balanced hardness and is used for applications like marine and chemical processing.

Ceramic: These are made using various materials like silicon nitride, zirconium oxide, and silicon carbide. Such bearings can withstand high temperatures and corrosion, offering excellent insulation.

Polyethylene: Polyethylene is a material for bearing that offers high chemical and impact resistance and is used in such applications where reliability is important.

Applications of Bearings

Bearings are widely used in various applications, and some of these are discussed below:

Automotive

The automobile sector uses bearings for supporting the movement and is loaded in different parts.

Some of the types of bearings used in vehicles consist of tapered rollers in the steering system. Also, needle roller bearings in the gearboxes and row ball bearings in the wheel hub.

Aerospace

Bearings are needed for the efficiency and optimal performance of aircraft; it is important for flight control and its performance. Landing gears consist of self-lubricating bearings, the fuel pump has tapered roller bearings, etc.

Medical

Bearings offer reliability and precision in medical equipment. In MRI machines, low-friction bearings ensure smooth operation and surgical tools require miniature bearings.

Railway

Railway applications have to handle heavy loads. To reduce wear and tear, axle bearings are widely used that help absorb shocks.

Marine

Marine applications require bearings that resist corrosion and perform well when subjected to harsh conditions. In propeller shafts, the bearings help to reduce friction, and also in rubber systems, self-aligning bearings offer smooth control of steering.

Industrial Machinery

Industrial machinery uses bearings in conveyors and motors to ensure smooth movement and reduced friction.

Consumer Products

Bearings are found in many consumer products for smooth functionality. Washing machines, refrigerators, and power tools use them for excellent functionality.

Conclusion

The significance of using bearings in different tools and equipment is highlighted above. So, if you are looking to have custom bearings designed for your application, DEK can help you.

We offer a wide range of types of bearings that are according to your application requirements and possess high quality and precision.