Many pieces of industrial and light-duty machinery, ranging from tiny grocery carts to massive power plants, depend on bearings in one way or another to operate.
Types of bearing come in many different shapes and sizes and are an essential tribological component of many different kinds of machinery. They can be characterized as a machine component that, in a system that may be subject to static or dynamic loading, only supports or permits a particular kind of motion (restriction of degrees of freedom).
A sliding door is one illustration. It is impossible to raise or move the door. It can only be opened by sliding. Bearings limit the range of motion to sliding motion.
Bearings for Rolling Elements
Rolling elements in the form of cylinders or balls are found in rolling element bearings. Since rolling friction is less than sliding friction, we know that rolling a wheel is easier than sliding it on the ground. Here, the same idea is at play. Rolling element bearings are used to allow components to move freely during rotation.
It is simple to transform rotating motion to sliding motion, even in applications where linear motion is required. Think of a conveyor or an escalator. Despite being linear, the motion is propelled by motor-driven rollers.
Another example is a reciprocating pump, which uses linkages to transform a motor’s rotational energy into translational motion. Motor shafts and the shafts of other rollers in the assembly are supported by ball bearings in each of these applications.
Rolling friction replaces sliding friction, allowing rolling elements to carry the load with minimal friction. Ball bearings and roller bearings are the two main categories of rolling element bearings.
Ball Bearings
One of the most widely used bearing classes is the ball bearing. It is made up of a line of rolling balls. Two pieces of metal in the shape of an annulus are trapping them. We call these bits of metal races. While the outer race remains still, the inner race is allowed to revolve.
Ball bearings have a limited ability to carry loads, but they offer extremely low rolling friction. The limited region of contact between the balls and the races is the reason of this. They can support axial loads in two directions besides radial loads.
Ball bearings are utilized for regulating oscillatory and rotational motion. For example, in electrical motors when the shaft is free to spin but the motor housing is not, ball bearings are utilized to link the shaft to the motor housing.
Depending on the application, different types of ball bearings are available to choose from.
Ball bearings’ benefits include:
Good resistance to wear
Not much lubrication is required.
Provide low friction, thus little energy loss
Long service life
Simple to swap out
Minimal overall dimensions
comparatively inexpensive
Can handle thrust loads
Disadvantages of ball bearings:
May break due to earthquakes
Quite noisy at times
Unable to manage heavy loads
Ball Bearings with Deep Grooves
The most popular kind of ball bearings are deep groove ball bearings. Trapped between the two races is a ring of balls that transmit the load and allows rotational motion between the two races. The balls are held in place by a retainer.
They have very low rolling friction and are built for minimal noise and low vibration. They are therefore perfect for applications requiring fast speeds.
They are very easy to install and need minimal upkeep. Since the races must be pushed into shafts, care must be given during installation to avoid denting them.
Ball Bearings with Angular Contact
In this ball bearing type, the inner and outer races are displaced with respect to each other along the bearing axis. Angular contact roller bearings are designed to handle greater amounts of axial loads in both directions in addition to radial loads.
The axial load can be transmitted to the housing through the bearing because of the change in the inner and outer races. Applications requiring tight axial guiding can benefit from this bearing.
Numerous high-speed applications, including CNC machining tool spindles, gearboxes, pumps, vehicles, and agricultural equipment employ angular contact bearings.
Ball bearings that align themselves
This type of ball bearing is immune to misalignment between the shaft and the housing which may happen due to shaft deflection or mounting errors.
The inner ring has deep grooves similar to deep groove ball bearings followed by two rows of balls and the outer ring. The outer ring has a concave form and this enables the inner ring some leeway to reorganize itself based on the misalignment.
Bearing Thrust Balls
Thrust ball bearings are a unique form of ball bearings built primarily for axial stresses. They cannot support radial loads at all.
Thrust ball bearings show minimal noise, smooth operation and are capable of high-speed applications.
They are available as single-direction or double-direction bearings and the selection relies on whether the load is unidirectional or bidirectional.
When to Use Ball Bearings?
So let’s detail some of the operating circumstances that may demand a ball bearing.
Thrust loads are present. Ball bearings’ design makes them capable of withstanding axial loads.
No big loads. The bearings focus all of the force on a small number of points of contact because of their ball-shaped rolling components. High loads may cause an early failure as a result.
fast speeds. There is also less friction because of the ball bearing’s narrow point of contact. With these kinds of bearings, it is therefore simpler to reach high speeds since there is less resistance to overcome.