Machines are comprised of several moving parts that need to work smoothly for proper functioning of the whole system. Bearings are tiny but essential components of machines used to reduce friction between those moving parts so that they move smoothly. Among many types of bearings, one is called an axial bearing, also known as a thrust bearing. These bearings are basically the bearings catering to the axial loads in different machine components.
Introduction of Axial Bearings
Axial bearings are famously known as thrust bearings, and are widely used to handle axial loads (acting parallel or along the axis of the shaft). Their design supports thrust forces without affecting the performance of the machines. They are the opposite of the radial bearings that cater to the forces acting perpendicular to the shaft, called radial loads.
They have different design variations as well, based on the application. Each one of these designs handles specific load carrying capacities and functioning requirements. These bearings have a compact structur,e so they don’t take much space. Hence, you can use them where the installation space is limited.
Since they support axial loads quite well, they pretty much reduce the unwanted stress of the other components of the machinery. This not only reduces wear but also improves machine efficiency. They increase the durability of the machines and help extend their service life as they distribute loads very evenly and reduce friction between the moving parts. There are different types of axial bearings, making them perfect to use in various industries.
Types of Axial Bearings
There are different types of axial bearings. Each of these bearings serves a specific purpose and performs according to the machine they are used for and the load they carry. Some of the most common axial bearing types you should know are discussed below:
1. Thrust Ball Bearings
These bearings are meant for low to medium axial loads. They are composed of two rings, a raceway, and tiny steel balls acting as rolling elements. These small balls enable the bearings to spin and rotate freely and smoothly. This helps reduce friction when axial forces are applied along the axis of the shaft. They are commonly found in many light-duty applications, including automotive parts, household appliances, fans, office equipment, and machine tools.
Whenever a load is pressed along the axis of the shaft, axial bearing balls roll between the rings, enabling the parts to move freely and reducing friction between them. They perform exceptionally well for low-speed machines where there is a minimum load involved.
Since they have a very basic, simple design, they are easy to install and are very cost-effective. However, you cannot use these bearings for high speed and high impact machinery. Also, they only cater to the axial forces, not radial ones.
2. Cylindrical Roller Thrust Bearings
As the name indicates, they have cylinder-shaped rolling elements instead of balls. Cylindrical roller thrust bearings carry heavier loads because of the rolling element’s larger surface area of contact. So, they are more reliable for a bit heavier loads compared to thrust ball bearings.
Their rolling elements are placed side by side, forming a straight line, and when a force is applied, they roll between flat raceways. Because of the presence of cylindrical rolling elements, they offer less friction to the moving parts of the machines than ball bearings.
You can find their applications in gearboxes, mining equipment, large industrial machines, large motors, and cranes. They have high load-carrying capacity, perform really well under tough conditions, and possess longer service life. There are some downsides too. Like ball bearings, they don’t support very high loads and misalignments, if they occur.
3. Tapered Roller Thrust Bearings
These bearings have unique rolling elements. They have conical rolling elements instead of balls or cylinder-shaped elements. These rollers are arranged differently from other rollers. They are positioned at an angle, which helps them not only support axial loads but radial loads to some extent as well.
When force is applied and bearings are loaded, the rollers roll between uniquely designed raceways and distribute the force evenly. This specialty makes them perfect for applications where force is not applied from only one direction.
Tapered roller thrust bearings are well-suited for heavy duty gearboxes, car wheels, and construction equipment. Their main benefit is that they can handle both loads (axial and radial) at the same time and perform excellent under stress in providing strong support to the moving parts of the machines. However, precise alignment and careful installation is needed for them.
4. Spherical Roller Thrust Bearings
Spherical roller thrust bearings have a curved raceway and rolling elements or rollers in a barrel shape. They are designed to handle misalignment in the shaft and housing, besides handling the axial loads.
They move or roll along a path that enables them to self-align. It means even if there is some misalignment in the shaft or the shaft is off-centre, the bearing will still perform quite well without compromising the structural integrity.
These bearings are used in vertical pumps, wind turbines, and applications where there are chances of misalignments. Their load-carrying capacity is excellent, can handle axial and radial loads (limited), and caters to misalignments too. But, they are expensive and take a little more space than other counterparts.
5. Needle Roller Thrust Bearings
Needle roller thrust bearings have very thin and long, needle-like rollers. Because of their design, they are very sleek and can fit any compact space and handle moderate axial loads along the axis of the shaft. The needles are inside two flat washers.
When the load is applied, the rollers carry that load across the wider surface area and reduce friction. They work well for compact mechanical assemblies, automotive transmissions, and gearboxes.
These bearings are light in weight, small in size, and perfect for limited spaces. However, their axial load-carrying capacity is limited and can be used for limited applications.
What is the Purpose of the Axial Bearing?
The main purpose of the axial bearings is to handle loads acting along the axis of the shaft. Without these bearings, the moving parts of the machinery rub against each other and don’t move freely, causing operational faults. Axial bearings keep those moving parts steady whenever a force is applied to push or pull them in the line of the shaft. So, not only do they handle axial loads, but they also prevent damage.
Apart from this, there are some other functions that axial bearings perform, including:
Reduce Friction
Whenever two parts rub against each other, they produce a lot of friction, heat, wasted energy, and wear and tear. Axial bearings decrease that friction, making the operation of machinery smooth and quiter.
Precise Movement
Tools, medical equipment, and machines need exact, precise movement to function accurately. Axial bearings offer controlled motion along the shaft. These bearings keep everything balanced and aligned, increasing safety and performance.
Reduce Misalignment & Damage
During operation, the forces on the shaft misalign the shaft and move it out of place a little if not supported properly. Axial bearings hold the shaft firmly without compromising the smooth motion. Hence, it helps prevent breakage, bending, or shakage.
What is the Difference Between Axial and Radial Bearings?
| Features | Axial Bearings | Radial Bearings |
| Load Direction | Support load along the axis of the shaft | Support load across the axis of the shaft |
| Main Purpose | To handle force pulling or pushing parallel to the shaft | To support the rotating components under sideways pressure |
| Shapes of Rolling Parts | Have balls or rollers placed in between angled or flat raceways | Comprises balls or rollers in spherical raceways |
| Applications | Used in machine spindles, automotive transmissions, turbines, aerospace, and electrical tools | Use in motors, pulleys, and wheels |
| Movement Allowed | Allows rotation and keeps the shaft in its perfect place | Allows seamless rotation around the shaft |
| Combination Use | Can be combined with radial bearings | Can be used alone or with axial bearings according to need |
| Misalignment | Spherical bearings allow limited misalignment | Some allow slight misalignments |
Conclusion
Axial bearings are essential in supporting loads along the axis of the shaft, called axial loads in different machine components. They not only handle axial loads but also reduce friction, allow precise movements, cater to misalignments, and prevent damage and wear and tear. These bearings are different from the radial bearings.
There are different types of axial bearings, including thrust ball bearings, cylindrical roller thrust bearings, tapered roller thrust bearings, spherical thrust bearings, and needle roller thrust bearings. Each of these bearings has a specific shape of rolling element. Hence, they are used for different purposes and cater to different applications. So, you can choose whatever is suitable for your application.
Contact BYWB Bearing for all types of axial bearings. We are leaders in the industry and have been working for quite some time, delivering across all parts of China and globally. So, contact right now!
