Bearings & rotating equipment : An insight and perspective
By Dr. Jyoti D. Vora , MSc., PhD, F.S.Sc. , MASFFBC, CME (USA), NET CLEARED, LZSI, FFC (USA)
A bearing is a machine element that constrains the relative motion to a desired motion, and reduces friction between moving parts. Due to its versatility of function, bearings find uses in almost all cadres of machines. Bearings fascinate anyone who is a curious learner of mechanics and engineering operations. Moreover, they touch our life day-t-day, through gadgets and products which improve societal and individual efficiency and comfort.
The invention and history
It is interesting to delve into the history of this simple mechanical gadget which man invented through his ingenuity and enterprise.
The invention of the rolling bearing, is of great antiquity. Egyptians, Roman drawings, Agostino Ramelli and even Leonardo Da Vinci are iconic in their contribution to bearings and their structural evolution.
If we discuss the basic methodology of function, they provide support to rotary components like shafts within mechanical systems, and transfer axial and radial loads from the source to the structure which provides support.
An overview of the direct co-relation between energy conservation and bearing usage has been well studied and documented.
The term “bearing” is derived from the verb “to bear”; a bearing being a machine element that allows one part to bear (i.e., to support) another. The simplest bearings are bearing surfaces, cut or formed into a part, with varying degrees of control over the form, size, roughness, and location of the surface. Other bearings are separate devices installed into a machine or machine part. The most sophisticated bearings for the most demanding applications are very precise components; their manufacture requires some of the highest standards of current technology.
Bearings are used between the rotating shaft and the machine part which supports rotation. They serve to ensure smoothness in rotation by friction reduction. Rotary bearings find use in gearboxes, motors, pulleys, fans, pumps and so on.
Bearings transfer motion and forces; they prevent wear and tear of the machine parts by reduction of heat generation. If we take a simple example of a motorbike, numerous bearings find their place in its profile. Some of them are loose balls, caged balls, bushings, needles, and cartridge and roller bearings.
They are used to support primarily radial loads and axial loads parallel to the axis in one direction. Additionally, they are essential in moderate to high-speed applications to reduce friction and enhance equipment speeds.
Industry’s bread and butter
As a matter of fact, bearings are so basic to the machine industry and science of mechanics that they have been called the industry’s “bread and butter”. They are used in every category of machine. Interestingly and ironically, they are obscure in their presentation and are termed as “shadow workers”. But because they do their work in the shadows, most people who are not involved in the machine industry probably do not know about this fascinating machine part! To understand how universally present bearings are to our day-to-day life, just note this fact: High-end cars have in their make-up more than 150 bearings! Each bearing in a car has a nodal role to play, from rotation to support to energy conservation to overall functionality.
The evolution
The evolution of bearings occurred from the Industrial Revolution onwards. This was marked by the era when steel production was at its height and mass production of steel bearings was widespread. Additionally, innovations were seen in the applications of bearings in every field of engineering.
Axles using bearings were one particularly important discovery of the industrial age. In bicycles, ball bearings were used as rolling elements. This concept became so popular that axles started being used in carriages which were drawn by horses. Looking back, this was a game-changer in development of movement and transport.
At around the same time in Industrial history, bearings started to be used in all variety of industrial machinery, contributing greatly to industrialization.
At this standpoint of Engineering acumen and technology and the development of industry, bearings are a presence that humankind would be unable to live without.
Notably, Japan’s bearing manufacturers refused to give in and showed grit and unity which is exemplary. They all pulled together, and were able to develop a manufacturing process for high-quality bearings. The precision and performance of bearings made in Japan were able not only to recover but to become icons of engineering technology, greater than ever before.
Taking a cue from Japanese engineering history
No treatise on bearings would be complete without the study of the Japanese Engineering history. To narrate the story from the beginning, Japan catered to an order of the Imperial Navy by producing the first bearing in 1916.The country has never looked back since then. Koyo Seiko started selling bearings as far back as 1921 and the future looked promising. As per the demand and supply equation, the Japanese domestic demand for bicycles was steadily growing, and cars made their appearance. All in all, it seemed that the Japanese bearing industry would advance and spread steadily.
However, World War II happened and extensive war damage was done to factories all over Japan, and the bearing industry suffered a significant setback.
Notably, Japan’s bearing manufacturers refused to give in and showed grit and unity which is exemplary. They all pulled together, and were able to develop a manufacturing process for high-quality bearings. The precision and performance of bearings made in Japan were able not only to recover but to become icons of engineering technology, greater than ever before.
As there is a substantial enhancement in motorization, novel bearings designed to improve the durability and reliability of cars continued to be developed, resulting in a massive boom in Japan’s domestic demand for bearings. Bearings played a key role in Japan’s miraculous economic growth in this era. This is a study of innovation, initiative and continued research-oriented proficiency.
At today’s standpoint, the precision and performance of Japanese bearings is recognized globally, allowing Japanese bearings to enter the international market. Now, with Japanese bearings renowned the world over, one third of all bearings on this planet Earth are the work of Japanese expertise in the arena of bearing technology.
As an accurate speculation, the history of the evolution of bearings is the history of the development of human civilization. If bearings had not been developed, humankind would probably still today be trying to exert massive force in order to move heavy objects, to say nothing of how we would almost certainly not have all the modern conveniences and comforts provided by machines.
To understand how universally present bearings are to our day-to-day life, just note this fact: High-end cars have in their make-up more than 150 bearings! Each bearing in a car has a nodal role to play, from rotation to support to energy conservation to overall functionality.
In conclusion
In a nutshell, the birth and evolution of bearings had an immeasurably large impact on the development of human civilization.
Bearings are an artifact of the ingenuity of our ancient ancestors, and played a key, if hidden, role in the history of industrialization. Indeed, they are the shadows which have defined the real image!!!
Bearings play a crucial role in our daily lives, but it is precisely because of their importance that we must constantly strive to make them more precise and durable.
Additionally, it is vital to the development of machine technology that we continue going forward to develop bearings that can work under ever harsher and more specialized conditions. Bearings will no doubt continue to evolve and change, and to improve our livelihoods by ‘making the world go round’.
Acknowledgement
The author acknowledges the use of authentic technical literature to structure this article.
