Archive for April, 2015

Bearing Installation Tools

Friday, April 24th, 2015

Over 15% of premature bearing failure can be attributed to a poorly fitted or mounted bearing, usually one that was mounted using too much brute force as opposed to proper mounting practices.

Installation is the first point of contact for your new bearing parts and your machine. It is quite important that you don’t go slapping on new bearings willy-nilly, as proper mounting is essential to ensuring long bearing life.

There are proper procedures and tools to help you perform installation properly. Check with the manufacturer and your distributors first, if you have questions regarding any specific application or issue.

There are tools and even nifty installation kits on the market to assist in facilitating safe, precise, and quick mounting of bearings. These help to avoid any damage to the shaft or raceways during mounting.

Remember, mounting isn’t a one and done-type ordeal. You will want to be certain your bearings are properly dismounted, and re-mounted after every maintenance endeavor, in order to ensure the longest-running life from them.

Different tools and kits will suit different preferences, as with most things, but take a look at the three big-name manufacturers’ offerings for a great selection of bearing installation and dismounting tools.

Timken’s impact fitting tool kit includes, shown here on their website, features:

  • 33 collets ranging from 10 mm to 110 mm
  • Three sleeves
  • One impact hammer

NTN also has installation and removal tools to make mounting and dismounting easier. Their range of products is a bit more application-specific, with mounting tools including:

  • Adjustable Spanner Wrenches
  • Mounting Tool Kit case
  • Heaters for Bearings, Rings, and Gears

And dismounting tools including:

  • Bore Pullers
  • Mechanical Pullers
  • Hydraulic Pullers
  • Pulling accessories for special applications

More information about their installation and dismounting tools can be found here.

SKF’s installation tool kit features:

  • 36 impact rings in different sizes facilitate the mounting of more than 400 different bearings
  • 3 impact sleeves
  • dead-blow hammer
  • lightweight carrying case

Further details about this product can be found here at their website.

Use SKF Speedi-Sleeve for Worn Shafts

Friday, April 17th, 2015

The Speedi-Sleeve is a thin-walled sleeve developed by manufacturer SKF, that is simply pushed into position over the worn area. This provides a surface that is then optimized for radial shaft seals, reducing costly downtime. And, there is no need to disassemble the shaft, or search for other seals since the same sized seal as the original can still be used. The only installation tool needed is supplied along with the shaft, so no special equipment is needed either. All you’ll need is a mallet and pair of pliers.

SKF Speedi-Sleeve Features: Through the stainless steel and manufacturing process, the speedi-sleeve provides an optimized seal that minimizes wear on the sleeve and the sealing lip, and increases strength and ductility. Its surface is wear resistant and made to minimize directionality – traits that are better than most counterface surfaces achievable on a shaft. It is complete with imperceptible lubricant pockets that allow the lubricant to sit on the sleeve, and prevent running of the sealing lip while it is dry, which would create excessive wear.

Installing SKF Speedi-Sleeve: The seal counterface surface of the shaft should be carefully cleaned, and any burrs or rough spots filed down before installation is attempted. If not properly cleaned, due to the thin-walled sleeve’s interference fit, any disturbances on the shaft surface may create a similar pattern on the sleeve surface and cause the seal to leak. If there are deep wear grooves, scratches or very rough surfaces, treat first with a suitable powdered metal filler, and position the sleeve before the filler has hardened. Take care the sleeve is not installed over keyways, cross holes, splines, or threads since this will result in deformation of the sleeve and will make it difficult to follow its new counterface surface as it rotates.

To simplify installation, the SKF Speedi-Sleeve has a removable flange, as well. The flange should be removed in applications where it may reduce the supply of lubricant to the seal, or in applications where it would interfere with other system components, but otherwise it can be left intact.

Also, the SKF Speedi-Sleeve should not be heated prior to installation. Using heat will cause the sleeve to expand, but when it cools, it may not contract back to its original size, resulting in a loose fit on the shaft.

Removing the SKF Speedi-Sleeve: Note that upon removal, the SKF Speedi-Sleeve cannot be reused. If needed, the sleeve can be removed by applying heat, which will expand it enough to let it slide off the shaft without causing damage to the shaft. In addition, the sleeve can be removed by relieving the press-fit tension using a small hammer to peel across the width of the sleeve, or using a cold chisel to cut through the sleeve, or a pair of wire cutters starting at the flange and twisting.

SKF Speedi-Sleeve Gold: There is also an enhanced version of the SKF Speedi-Sleeve, that has increased durability and resistance to abrasive wear. A thin, metallic coating is applied to the base stainless steel of the SKF Speedi-Sleeve, and imparts a gold color along with enhanced features. It was designed for applications where extended sealing system life is required, and to essentially bridge the performance gap between the standard sleeve, and acquiring an expensive custom shaft treatment. The SKF Speedi-Sleeve Gold is especially effective in environments where there are abrasive contaminants. Note that the installation procedure is the same as for the standard Speedi-Sleeve, and the original seal size can still be used.

Test results: To ensure optimal performance, the SKF Speedi-Sleeve Gold has been extensively tested in order to establish its level of abrasion resistance in severely contaminated environments. Tested using both coarse and fine sand, and at temperatures up to 225 °F and shaft speeds up to 1 700 ft/min. Under these conditions, seals on SKF Speedi-Sleeve Gold ran for an average of 2500 hours. Just another reason SKF is among the largest, and most reliable bearings manufacturers on the market today.

Global Demand for Bearings – 2018 Predictions

Friday, April 10th, 2015

At the start of the economic crisis in 2008, we observed decreases for bearing turnover and types, and little recovery in the bearings market, until this past year.

Fortunately for the bearing industry, there looks to be a bright and profitable future nearby.

Global demand for ball, roller, and plain bearings is projected to rise 7.3% annually to $104.5 billion in 2018, according to Global Industry Analysts, Inc. (GIA). This revenue will be driven by strong gross fixed investment and robust product output growth as worldwide economic conditions improve.

The analysts at GIA predict the Asia-Pacific region to encounter the largest amount of growth between now and 2016 by around 10% per year. The region is anticipated to reach $54 billion for total bearings turnover in 2016.

Likewise bringing about value gains is a definite switch in the available product mix toward more expensive, better-performing units, backed by progressively complicated designs in bearing-using goods, and by high energy costs which make highly efficient bearings a very attractive investment. These and other trends are presented in World Bearings, a new study from The Freedonia Group, a Cleveland-based market research firm. http://www.freedoniagroup.com.

“China will post the strongest gains of any national market in dollar terms,” states analyst Ken Long. “In fact, almost half of all additional product demand through 2018 will be accounted for by China,” he says.

India — a substantially lesser, but nevertheless sizeable bearing market — is predicted to register much larger annual increases in percentage terms. The prediction is similar for several smaller markets — including Iran, Indonesia, Turkey, Thailand, and Malaysia — which are also expected to record healthy sales progress.

US demand for bearings is projected to climb at a 5.9% annual pace through 2018, representing one of the strongest market performances of any developed nation. This is driven by momentum in economic growth, and durable goods output.

Merchandise, particularly those in the technology and electronics sectors, have begun being designed at a rapid-fire pace. The bearing industry will have to meet the demands of products by shortening the development time, and eliminating the cumbersome bearing manufacturing time that has become the industry standard.

Improvements in the bearing industry will likely be restricted by typically slow increases in durable goods production, and in the case of Japan, additional decreases in motor vehicle production.

Source: bearing-news.com

Angular Contact Bearings

Friday, April 3rd, 2015

DEFINITION:

Angular Contact Bearings are constructional bearings which use the rolling element of the ‘ball’. This is another common type of bearing using the ball as the rolling element. This type of bearing is composed of many steel balls, kept together by a cage, set between two races.

The internal design of an angular contact bearing is meant to take on radial load, as well as moderate axial load from one side only. The contact angle is defined as the angle between the line joining the points of contact of the ball and the raceways in the radial plane, along which the load is transmitted from one raceway to another, and a line perpendicular to the bearing axis. This contact angle varies from about 25° to 40

Angular contact bearings can support fairly heavy axial loads in one direction in addition to radial loads. The axial load carrying capacity of angular contact ball bearings increases with increasing contact angle.

SINGLE ROW ANGULAR CONTACT

Single row angular contact ball bearings feature raceways with high and low shoulders. These opposing raceways are designed to carry thrust load in one direction.

DOUBLE ROW ANGULAR CONTACT

Double Row Angular Contact ball bearings have two rows of balls arranged back-to-back. In essence, they work similarly to having a matched pair of Single Row Angular Contact ball bearings. The difference is that Double Row Angular Contact ball bearings can take a bi-directional axial load in one bearing where it takes a matched pair otherwise.

APPLICATIONS:

Angular contact ball bearings are suitable for applications which require high accuracy and good high-speed performance.

Most bicycles use angular-contact bearings in the headsets because the forces on these bearings are in both the radial and axial direction.

Higher speed applications include turbines, jet engines, and dentistry equipment.

MOUNTING:

They can be mounted (flush) in sets of two or more, with regards to the application. To ensure that these bearings operate properly, they must be assembled with a thrust load. This loading, or preloading, creates a contact angle between the inner race, the ball, and the outer race. The preload can be built into the bearing or created when the bearing is inserted into an assembly.

CONSTRUCTION:

Angular contact bearings may be constructed of materials such as stainless steel, plastic, and ceramic hybrid. They may also be plated – common plating materials are cadmium and chrome.

LUBRICATION:

Angular contact bearings have a variety of lubrication options. They can be re-lubricated, pre-lubricated, or have solid lubrication.

SEALS:

Single row and double row angular contact bearings can be supplied with or without shields or seals, depending on the customer’s request and the requirements of the application.