Archive for March, 2011

Timken — Corporate overview

Thursday, March 31st, 2011

History of The Timken Company

For more than 100 years, Timken has focused on value creation for diverse industries and market segments. We deliver a variety of friction management and power transmission solutions for applications ranging from aircraft and automobiles to mining equipment and medical instruments.  We’ve grown considerably since our founding in 1899, but solving customer problems is still at the core of our business, just like it was when founder Henry Timken patented a tapered roller bearing design that made life easier for freight wagon operators and their mules.

The Beginning

Henry Timken, a St. Louis carriage maker, recognized that heavy freight wagons had a hard time making sharp turns. To solve the problem, he applied a tapered roller bearing design that could handle both radial (weight) and thrust (cornering force) loads. There were several customer benefits. First, the application ran more smoothly, reducing repair and replacement costs. In some cases, the bearings improved wagon performance so much that fewer mules were required to pull them. Finally, better cornering meant less chance of losing a load of goods. Always focused on customer benefit, Henry quickly realized that the tapered roller bearing could improve product performance in many other applications as well. He and his sons, H.H. and William Timken, quickly founded The Timken Roller Bearing and Axle Company and began building the business into what it is today.

Corporate Overview 

Wherever there is motion, you’ll find Timken at work. Timken is one of the world’s leading producers of highly engineered antifriction bearings and related products and services and alloy steel and components. We help create, transfer and control power, putting our friction management and power transmission technologies to work across a broad industry spectrum.

Timken has operations in 27 countries on six continents, and our team of 20,000 employees is dedicated to improving our customers’ performance in a variety of applications.

Manufacturer and worldwide supplier of the highest quality rod ends and spherical bearings — ANYWHERE!

Tuesday, March 29th, 2011

In 1971 a new company entered the rod end and spherical bearing marketplace.  This new firm, Aurora Bearing Company, soon became a major force in the rod end industry. 

Known primarily for a high quality product and a strong committment to customer service, the firm dramatically increased its market coverage and now serves nearly every industry and aerospace market.  These markets include among others; textile and packaging  machinery, machine tools, business machines, recreation and exercise equipment, agricultural and off highway vehicles as well as military equipment and commercial air and space craft.

Over the years, Aurora Bearing has retained its original business philosophy of furnishing a high quality product at competitive prices of furnishing a high quality product at competitive prices.  In addition, the company’s initial goals of providing prompt delivery and furnishing service with a personal touch have been rigidly maintained.

Aurora Bearing offers a complete line of standard rod end and spherical bearings.  They also design and manufacturer special bearings to meet a variety of applications that require custom engineered units or special materials.

Aurora will be the next database put up on the website.

It’s been 1 month now …

Thursday, March 24th, 2011

and we were pleasantly surprised that we exceeded our first month goals….And I’m very pleased with the results of our new Website at Bearings Incorporated .  Thank you for your help !

Come on .. let’s take a refresher tour …

Not only can you purchase bearings, with our stock being revealed more and more on a constant basis; you can read up on our history, you can check out our manufacturers, with links to some and more to come. Stop in and check out our testimonials to see what our customers really think of us.

Currently our site only takes Paypal or Credit card, but we have plans for the future of adding open account as an option (with prior approval of course). To find forms for entertaining the idea of opening an account with us, check out our Forms page. You can also use this page, if you reside in the state of Wisconsin; and are tax exempt, a few clicks, and you have a valid Tax certificate for filling out and forwarding to us.

And of course, our contact us page in which you can inquire about purchasing our products. Just because it may not be listed doesn’t mean that we can’t get it. We will be changing the on line stock items on a regular basis, and it will take time for us to upload all of the available vendors we have.

And then last but not least — the blog connection .. which completes our circle, as it will attach directly back to here.

I must apologize however, as we are set up to do business only within the 48 US continental states. We do not export outside of this parameter.

Let’s make our second week even better!

Thank you again for your present and future patronage!

SELECTION FOR SIZE AND SERIES With Regard to LIFE Expectation — Part 4

Tuesday, March 22nd, 2011

Life Expectancy

Load rating to be of the greatest help in the selection of a bearing for an application must be, for all types and sizes and for any speed, based on a single index of life expectancy for a given factor of safety. , These figures, as before mentioned, apply not to individual bearings but to groups of bearings large enough to permit the law of averages to become adequately effective. Following is a table of multipliers which, when applied to Fafnir ratings, will covert them to life expectancy figures (under a factor of safety of one) other than 3500 hours.

To convert Fafnir ratings to other life bases multiply by these factors:

10,000 hours —- .705
5,000 hours ——-.884
2,500 hours ——1.119

Safety Factors

The safety factor under which a bearing operates is the ration of its rated capacity at the operating speed to the load applied. Where combined thrust and radial loads are imposed on the bearing, the equivalent load of one type or the other must be calculated from the formula for each type of bearing. In the case of the bearings rated for radial capacity, the radial equivalent must be determined, and conversely for thrust-rated bearings.

When accurately known, the safety factor is a direct indicator of life expectancy, assuming a constant load (and, of course, proper installation and maintenance of the bearing). For example, a bearing, which takes only the weight of a balanced flywheel, and has a safety factor of 1, will have a life expectancy of 3500 hours. If in addition to the steady load from the flywheel a light shock load of variable amount is imposed, either constantly or intermittently, the actual safety factor will be somewhat less than 1, and the life expectancy will be somewhat less than 3500 hours. In order to bring the actual life expectancy up to 3500 hours, the safely factor must be raised by incorporating additional bearing capacity in the application. This simple case can arbitrarily be broken down to show the primary and secondary functions of the safety factor, namely as a life indicator and as a service condition compensator, respectively; though the two functions are never really separable and the life expectancy still remains governed by the actual realized safety factor, incalculable or variable as it may be.

The determination of amount and type of bearing load and speed is simply a means of arriving at the safety factor for a given application, and that in turn makes possible the intelligent selection of bearing size or type. For instance, the desired non-failure life of an automobile differential might be two thousand hours, while the desired life of a certain type of textile equipment is many times that figure. Obviously, for a given load-speed condition in the two applications, considerably different bearings should be selected. Consequently, consideration must be given to the expected life of the machine as a whole. But since service conditions also influence expected life, the two are inextricably mingled in the correct bearing selection.

Happy St Paddies to all !!!!

Thursday, March 17th, 2011

 

May St Paddy bring you the money you need to pay your bills, the luck you need to be happy, and all your wishes come to reality.

HAPPY ST PATRICKS DAY !!!!

Selection For Size and Series With Regard to LIFE Expectation – Part 3

Tuesday, March 15th, 2011

Load Ratings

In order properly to rate the capacity of a ball bearing, its load-speed properties must be related to length of life.  With no such relation, load-speed curves are of little or no value, since the endurance-time (the third dimension of bearing ability) is missing.  The analogy of the length of time required for a quantity of water to flow from a vessel is strikingly accurate:  bearing load corresponding to hydrostatic pressure, and bearing speed to the size of the orifice through which the water is expelled.

Published load ratings are derived from the quasi-theoretical results of laboratory tests plus a “factor of experience”.  This “factor of experience” scales down the laboratory test results to values of load-life which can be expected to represent average values obtainable under average service conditions.  It is, in effect, an attempt to interpret laboratory test data into terms of useful life.  Since ball bearings have been used in an innumerable quantity of different applications, each operating under varying conditions, and since the interpretation is based on human judgment, it is only natural to find that the load ratings of various makes of bearing differ widely, even when compared on equal life bases with respect to bearing size, speed and expected life.  Load ratings are at best only an approximate guide as to what may be expected of a bearing in a given applications.  Indeed, it has been estimated that only a moderate proportion of all bearings fail “normally” in service; that the useful life of a large proportion is considerably reduced due to misapplication, such as improper  lubrication, contamination by foreign substances during or after mounting, improper shaft or housing fits or by actual abuse in handling.

Moreover, the publishing of high load ratings as a sales argument, besides tending to confuse the buyer, can be, and usually is, a reflection upon the optimism and sometimes the lack of engineering soundness of the bearing maker which exploits them. 

There are a number of mathematical methods of deriving load rating, each method having its own peculiarities as to the position and shape of the load-speed curve and the safety factor-life curve.  Actually the quasi-theoretical basis on which load ratings are established is of secondary importance as long as it is logically comparative and can be practically checked by experience in successful use.

Tuesday; March 22, Selection for size and series with regard to life expectation – Part 4

Fafnir bearings – Selection for Size and Series … Part 2

Thursday, March 10th, 2011

… With regard to LIFE expectation

Load-Life Characteristics

The load-life characteristics of a ball bearing may be defined as its ability to carry certain loads at certain speed for a duration of time.  Or, load-life may be expressed in terms of pounds-revolutions.  It is a measure of the inherent usefulness, just as a power plant may be judged by the number of horsepower hours which it delivers before failure.

For fatigue resistance, ball bearing steel must be of correct chemical composition and proper metallurgical structure.  It must be as free from nonmetallic inclusions as possible and there must be proper dispersion of its constituents.  Workmanship manifests itself in the adherence to precise dimensional tolerances, and the obtaining of extremely smooth surface finishes.  Since fatigue failure depends on the number and the magnitude of stress reversals, design plays an important part in the potential life of a ball bearing.  For example, the number of stress reversals for one revolution of a bearing depends on the number of balls and the ratio of the diameter of the rotating race to the ball diameter.  The magnitude of unit stresses for a given applied load is dependent on the area of contact between balls and races.  This contact area is in turn dependent upon the number of balls, their diameter and the degree of conformity of race curvature to ball curvature.  From these facts the largest possible ball size consistent with adequate structural strength of inner and outer rings is clearly indicated.  In fact, where material, workmanship and other design features are equal, the inherent capacity of a ball bearing varies as the value of Nd2 where “N” represents the number of balls and “d” their diameter.

The maximum potential life of a ball bearing can only be determined by actual breakdown tests, where all destroying influences except fatigue of metal are either removed or become a constant value over all groups of test bearings.  For example, shaft misalignment or deflection is minimized; fits between bearing bore and shaft, and between bearing outside diameter and housing are carefully controlled; and lubrication is provided by a circulating oil system.

Even with all variables reduced to a minimum, the disparity between the load-life characteristic of individual bearings of the same size operating under exactly similar loads and speeds is considerable.  It is necessary, therefore, to test large groups of bearings to arrive at dependable average life values.  In this respect, the “mortality” of ball bearings is not unlike human mortality.  It is impossible to predict the life of any individual, but the study of an enormous amount of individual life data has resulted in the highly reliable averages which are used by life insurance companies in figuring the probability of life for an individual.  It should be borne in mind that all data here relating to bearing life represents a probability or life expectancy which will be found to hold remarkably true over a sufficiently large number of cases.  In actual service, however, ball bearings are usually subjected to destroying influences not present under the laboratory test conditions.  Briefly summarized, these are:

Impact or shock loading; overload due to vibrations, misalignment or excessively heavy press fits on shaft or in housing; inadequate lubrication, high temperature, the presence of abrasive of abrasive material or corrosive liquids or gases.

The effect of these destroying influences is to subtract from the maximum potential life a certain amount which might be called “wasted life,” leaving a remainder which is “useful life”.  While this conception of the composition of bearing life is a purely artificial analysis, it nevertheless will be found useful in the understanding of practical aspects of proper bearing selection.

Next Load Ratings … Part 3 on March 15, 2011