Bearings have been in every day life for years

If you think about it; more than 4500 years ago, Egyptians used cylindrical rollers to move large heavy blocks of stone need for pyramids, preempting the use of ball bearings.

Similar usage was done in the creation of Stonehenge years later.

Leonardo de Vinci discovered the principle of the bearing in the 15th century. He realized that friction could be reduced if the balls did not touch each other. With this realization he designed separators allowing the balls to move freely. This design was reinvented in the 18th century when a horse carriage axle fitted with a ring of balls rolling in semi-circular grooves made in teh axle was patented in England.

Bearings have been a part of every day life for years.

Computers have bearings in the hard drives.
Exercise equipment is equipped with various bearings

Ball bearings are used in daily objects such as:

•     electric guitars
•     bicycles
•     video game controllers
•     blenders
•     camcorders
•     garage door openers
•     hot tubs
•     aquarium water pumps and aerators
•     roll and in line skates
•     cellphones

Yes — even Cellphones .. What makes the phone vibrate.  The phone vibrates from a tiny motor — which uses bearings in which to run.

The Hubble telescope and weather satellites are classic examples of ball bearings as part of the highest technology.

What Are Tapered Roller Bearings?

Tapered roller bearings comprise of an outer ring, an inner ring, rollers, and a cage profiled to ensure even distribution of the load. At low to intermediate speeds, they have high axial and radial load capacities.

Tapered Roller Bearings Design

You can find tapered roller bearings in single-row, two-row, and four-row designs.

For the single-row bearings, thrust capacity is around 60 percent of the radial capacity.

The two-row bearings can handle thrust loads in both directions and have a higher radial load capacity.

You can configure the rollers in such a way that contact lines between the race and roller diverges or converges towards the axis of rotation. The diverging two-row bearings increase the rigidity of the shaft mounting while the converging double-row bearings do not.

The two-row bearings also have other configurations including two outer rings and a single inner ring as well as a single outer ring and two inner rings.

Four-row bearings consist of four rows of alternating diverging and converging rollers.

Materials Used In Tapered Roller Bearings

The most common materials used in the manufacture of tapered roller bearings are low-carbon steels and alloy steels. Some applications do require use of through-hardened or case-hardened, high-carbon, bearing-quality steel.

The high-carbon steel does not require carburizing and are either through-hardened via conventional heating methods or case-hardened via induction heating.

When low-carbon, carburized steel is used, the carbon is introduced once the roller bearings are machined to a depth sufficient to produce a hardened case with the ability to sustain bearing loads.

The inclusion of alloys and carbon ensured the proper combination of a ductile and tough core as well as a hard case resistant to fatigue.

Choosing Tapered Roller Bearings

When choosing tapered roller bearings, the outside diameter (OD) and bore size are important considerations.

The smallest dimension of the bearing is the bore size. The outside diameter includes the housing of the bearing but not the flange. Other important considerations include the static axial load, rated speed, static radial load, dynamic radial load, dynamic axial load, and overall width.

The static radial and static axial loads are, respectively, the maximum radial and axial loads that a bearing can withstand without deforming permanently.

The dynamic radial load and dynamic axial loads are, respectively, the calculated radial and axial loads under which a group of similar bearings that have stationary outer rings can withstand for a rating life of a million rotations of the inner ring.

Hopefully, this gives you some insight into exactly what tapered roller bearings are, the important considerations when buying, and the types available.

Ball Bearing Components by MBP-Bearings.com

Ball bearings are comprised of four major parts: a large ring (outer ring), a small ring (inner ring), balls between the rings (steel balls), and a cage to prevent the balls from hitting each other.

The modern structure dates back to around 1500, when Leonardo da Vinci invented ball bearings to reduce friction against the axles of horsedrawn carts. For more than 500 years, the ball bearing has been defined by this simple structure.

Contact us

MBP BEARINGS PVT. LTD.
902/290, SHALIMAR INDUSTRIAL AREA,
NEAR LANE NO. 3,
MAIN ROAD, Delhi - 110088, India

Tips on How to Pick Wheel Bearings?

1. Precision Ball Bearings

Our most popular bearings are best suited for applications that require rolling ease, but where side thrust isn’t a critical factor. Pre-lubricated and sealed at the factory, they reduce maintenance costs because greasing isn’t needed. Double-sealed precision ball bearings feature steel-reinforced rubber seals securely fastened to a groove on the ring of both sides of the bearing.

2. Shielded Stainless Steel Ball Bearings

These bearings prevent rust and improve rollability in our stainless steel and solid urethane wheels. Can be custom spec’d in various sizes and configurations – including flanged, sealed square bores, extended inner raceways, and wide inner raceways with self-locking collars.

3. Precision Tapered Bearings

Recommended for heavy duty and power-towed applications, tapered bearings handle the most severe downward and side forces. Used in various wheels and swivel assemblies, they come in pairs – one on each hub side. Each consists of a cup (hardened and ground outer raceway) and cone (roller assembly). They extend overall wheel hub length by about ¼ of an inch.

 4. Plastic Bearings

For environments detrimental to metal bearings, acetyl resin bearings offer chemical and corrosion resistance. Delrin is standard in certain wheels, as either a sleeve or flange type bearing. Spherical bearings can be custom machined and installed in most other Hamilton wheels. Note: flange type bearings extend actual hub length of wheel by about 3/16 of an inch.

5. Oilless Sleeve Bearings
A sleeve, usually of sintered iron or oil-impregnated bronze, is press-fit into the wheel bore. While these bearings lack the rolling ease that anti-friction bearings provide, they are practical for light loads or applications where re-lubrication is a problem. (A light application of oil or graphite improves rollability and extends bearing life.)

6. Special or Custom Bearings

While standard bearings can handle most applications, some jobs may require bearings with special features, or a custom-engineered solution. For example, alloy bronze and ferrous alloy bearings withstand high heat. Teflon impregnated bronze bearings are self lubricating and roll in harsh environments. Roller clutch bearings allow a wheel to roll in only one direction and square bearings allow wheels to roll on a square shaft. 

The Basics of Ball Bearings

The concept behind a bearing is very simple: Things roll better than they slide. The wheels on your car are like big bearings. If you had something like skis instead of wheels, your car would be a lot more difficult to push down the road.That is because when things slide, the friction between them causes a force that tends to slow them down. But if the two surfaces can roll over each other, the friction is greatly reduced.

Bearings reduce friction by providing smooth metal balls or rollers, and a smooth inner and outer metal surface for the balls to roll against. These balls or rollers "bear" the load, allowing the device to spin smoothly.

Bearing Loads

Bearings typically have to deal with two kinds of loading, radial and thrust. Depending on where the bearing is being used, it may see all radial loading, all thrust loading or a combination of both. The bearings in the electric motor and the pulley pictured above face only a radial load. In this case, most of the load comes from the tension in the belt connecting the two pulleys.

The bearing  is like the one in a barstool. It is loaded purely in thrust, and the entire load comes from the weight of the person sitting on the stool. The bearing  is like the one in the hub of your car wheel. This bearing has to support both a radial load and a thrust load. The radial load comes from the weight of the car, the thrust load comes from the cornering forces when you go around a turn.

Bearing failure
A prematurely failed rear bearing cone from a mountain bicycle, caused by a combination of pitting due to wet conditions, improper lubrication, and fatigue from frequent shock loading.

Rolling-element bearings often work well in non-ideal conditions, but sometimes minor problems cause bearings to fail quickly and mysteriously. For example, with a stationary (non-rotating) load, small vibrations can gradually press out the lubricant between the races and rollers or balls (false brinelling). Without lubricant the bearing fails, even though it is not rotating and thus is apparently not being used. For these sorts of reasons, much of bearing design is about failure analysis.

There are three usual limits to the lifetime or load capacity of a bearing: abrasion, fatigue and pressure-induced welding. Abrasion is when the surface is eroded by hard contaminants scraping at the bearing materials. Fatigue is when a material breaks after it is repeatedly loaded and released. Where the ball or roller touches the race there is always some deformation, and hence a risk of fatigue. Smaller balls or rollers deform more sharply, and so tend to fatigue faster. Pressure-induced welding is when two metal pieces are pressed together at very high pressure and they become one. Although balls, rollers and races may look smooth, they are microscopically rough. Thus, there are high-pressure spots which push away the bearing lubricant. Sometimes, the resulting metal-to-metal contact welds a microscopic part of the ball or roller to the race. As the bearing continues to rotate, the weld is then torn apart, but it may leave race welded to bearing or bearing welded to race.

Although there are many other apparent causes of bearing failure, most can be reduced to these three. For example, a bearing which is run dry of lubricant fails not because it is "without lubricant", but because lack of lubrication leads to fatigue and welding, and the resulting wear debris can cause abrasion. Similar events occur in false brinelling damage. In high speed applications, the oil flow also reduces the bearing metal temperature by convection. The oil becomes the heat sink for the friction losses generated by the bearing.

ISO has categorised bearing failures into a document Numbered ISO 15243.

ARB Bearings Limited
H-22, Udyog Nagar
New Delhi - 110041, Delhi, India
Phone: +(91)-(11)-25471274 / 25471255 / 25186300
Fax: +(91)-(11)-25475455 / 25470126
Email: info@arb-bearings.com, export@arb-bearings.com, sales@arb-bearings.com
For Export Enquiry : 
Mr. Divay Rathee : +91-9968373086
Website: http://arb-bearings.com/contact-us.php

The Role of Bearings in Bicycle

The bicycle is a self-explanatory machine. Almost every part of it is there to be seen at a glance. So it's all too easy to neglect or underestimate the hidden ball bearings which keep the moving parts on the move.In any mechanical device, where two bearing surfaces make frictional contact with each other, some means must be found of minimising the friction.

In many cases, a well-lubricated "plain" bearing will do the job, especially if the bush is of phosphor-bronze or some similar hard alloy. In the more advanced "ball" bearing, however, the load or thrust is borne by a number of hardened alloy-steel balls which are themselves free to move along a narrow circular channel or "race." In a theoretically ideal ball-bearing, the load is concentrated at areas which are merely points. The steel balls are theoretically perfect spheres and therefore make direct contact with the opposing surfaces at two points, reducing the area liable to frictional wear to an absolute minimum. Also, as the balls themselves are of a specially-hardened steel and are free to move in a rolling manner, any slight amount of wear which they undergo during the course of time will be equalised over the entire surfaces of the balls. The balls, therefore, may ultimately become slightly reduced in size, but they will all be reduced equally; and thus they will keep their spherical shape, so that the working efficiency of the ball bearing is maintained.

In practice, ball-bearings are not perfect in their proportions, and signs of wear occur after a time. A theoretically perfect ball bearing would need no lubrication at all. Since it is impossible to manufacture absolutely spherical hardened steel balls, a true rolling motion of the balls within their race cannot be guaranteed; and the ball-race itself is always slightly concave - this concavity increasing with wear. So commercial ball-bearings must be lubricated.

*All ball-bearings in a bicycle should be dismantled and examined at the minimum once a year. Twice a year is much better. If the balls have not been adequately lubricated they will be worn sharp or rough, with small pits or depressions in the surfaces of the races. The best thing to do with such an article is to chuck it out.

Generally speaking, the balls themselves are the first to show signs of wear, and replacing them, with new balls will be enough to make the bearing like new. But the slightest sign of pitting in a hub-cone, or a crown-race, or a bracket-cup, should mean its instant relegation to the dust bin. Fitting new balls to worn races will simply ensure the rapid destruction of yet another set of balls.It sometimes happens that a ball will crack, breaking up into small fragments. Generally, this fault is detected soon after it has occurred; particularly if the cracking has taken place in the head-assembly or the bracket-interiors.

Do not merely replace the defective ball with a new one. Replace ALL the balls in that race. This makes sure that all the balls in the race are of uniform size. If a new ball has a slightly larger diameter than the old worn balls it will have to bear a far greater share of the load. It will come under excessive strain, probably resulting in a repeat performance of the original trouble!Dirt and dust are great enemies of ball bearings and if not kept out of the bearing, will set up friction between the individual balls in the race, preventing them from rolling freely. "Sticking" and "sliding" will result; this erratic behaviour will soon wear depressions into the race and will gradually destroy the entire bearing. This is why the efficiency of the hub dust-caps or other covering, should be carefully maintained.

The best lubricant for a ball-bearing consists of a medium-thin grease, filling the hubs, bracket, and head, with the excess wiped away after assembly. Pedals and (some) gear-pulleys are also fitted with ball-bearings, so don't forget these usually neglected items.The steel balls will thus become covered with a thin layer of lubricant which will not only reduce frictional wear at their points of contact within the race, but will also minimise the inevitable friction between the balls themselves.If you have any doubt as to the number of balls to put into a race, simply fill it and then remove one ball. The number of balls should NEVER be over-estimated; it would be better to under-estimate. An over-filled race will always jam -sooner or later. Similarly, it is the lesser of two faults if a bearing is slightly loose, rather than even fractionally tight.

 One big thing has changed though; twenty odd years ago most cycle components had no significant bearing seals. They relied heavily on the water resistance of the grease itself to keep the water out. It was only the invention of the mountain bike and people riding through muddy puddles up to their axles which forced component manufacturers to significantly improve the quality of their seals. As a result, modern quality cycle parts don't need re-greasing every six months. Many in fact are sealed for life and we are seeing more and more sealed cartridge bearings being specced as standard equipment.

ARB Bearings Limited
H-22, Udyog Nagar
New Delhi - 110041, Delhi, India
Phone: +(91)-(11)-25471274 / 25471255 / 25186300
Fax: +(91)-(11)-25475455 / 25470126
Email: info@arb-bearings.com, export@arb-bearings.com, sales@arb-bearings.com
For Export Enquiry : 
Mr. Divay Rathee : +91-9968373086
Website: http://arb-bearings.com/contact-us.php

Some Interesting Uses of Bearings

There are several types of bearings, and each has its own interesting uses, including magnetic bearings and giant roller bearings.

Magnetic Bearings  Some very high-speed devices, like advanced flywheel energy storage systems, use magnet bearings. These bearings allow the flywheel to float on a magnetic field created by the bearing.Some of the flywheels run at speeds in excess of 50,000 revolutions per minute (rpm). Normal bearings with rollers or balls would melt down or explode at these speeds. The magnetic bearing has no moving parts, so it can handle these incredible speeds.

Giant Roller Bearings Probably the first use of a bearing was back when the Egyptians were building the pyramids. They put round logs under the heavy stones so that they could roll them to the  building site.This method is still used today when large, very heavy objects like the Cape Hatteras lighthouse need to be moved.

Earthquake-Proof Buildings The new San Francisco International Airport uses many advanced building technologies to help it withstand earthquakes. One of these technologies involves giant ball bearings. to see the earthquake bearing support system at work.The 267 columns that support the weight of the airport each ride on a 5-foot-diameter (1.5-meter) steel ball bearing. The ball rests in a concave base that is connected to the ground. In the event of an earthquake, the ground can move 20 inches (51 cm) in any direction. The columns that rest on the balls move somewhat less than this as they roll around in their bases, which helps isolate the building from the motion of the ground. When the earthquake is over, gravity pulls the columns back to the center of their bases.

Protecting bearings is critical to a motor's reliability and useful life.

That's why Baldor Electric Company, Fort Smith, Ark., is now using Exxon Polyrex EM polyurea grease to extend bearing life in its industrial electric motors from 1/50 to 1,500 hp.In tests to 350°F, the new grease reportedly extends lubrication life for bearings by more than four times when compared to other polyurea greases. It is also more durable when subjected to mechanical shearing forces, says the company. A specially formulated additive system resists washout, rust, and corrosion, even when exposed to saltwater.

ARB Bearings Limited
H-22, Udyog Nagar
New Delhi - 110041, Delhi, India
Phone: +(91)-(11)-25471274 / 25471255 / 25186300
Fax: +(91)-(11)-25475455 / 25470126
Email: info@arb-bearings.com, export@arb-bearings.com, sales@arb-bearings.com
For Export Enquiry : 
Mr. Divay Rathee : +91-9968373086
Website: http://arb-bearings.com/contact-us.php