Cylindrical roller bearings

SKF Cylindrical roller bearings are available in a wide range of designs, series, variants and sizes. The main design differences are the number of roller rows and the inner/outer ring flanges as well as cage designs and materials.

The bearings can meet the challenges of applications faced with heavy radial loads and high speeds. Accommodating axial displacement (except for bearings with flanges on both the inner and outer rings), they offer high stiffness, low friction and long service life.

Cylindrical roller bearings are also available in sealed or split designs. In sealed bearings, the rollers are protected from contaminants, water and dust, while providing lubricant retention and contaminant exclusion. This provides lower friction and longer service life. Split bearings are intended primarily for bearing arrangements which are difficult to access, such as crank shafts, where they simplify maintenance and replacements.

Needle roller bearings

SKF needle roller bearings are bearings with cylindrical rollers that are small in diameter relative to their length. The modified roller/raceway profile prevents stress peaks to extend bearing service life.

SKF supplies needle roller bearings in many different designs, series and in a wide range of sizes, which makes them appropriate for a wide variety of operating conditions and applications.

Tapered roller bearings

With a wide range of designs to choose from, SKF tapered roller bearings are also customizable to match your specific speed, load, contamination, temperature or vibration conditions.

SKF Tapered roller bearings feature a cup and cone assembly. The cup is comprised of the outer ring and the cone assembly consists of inner ring, rollers, and cage. This bearing construction accommodates combined loads and provides low friction during operation. By adjusting one single row tapered roller bearing against a second tapered roller bearing and applying a preload, a rigid bearing application can be achieved.

SKF tapered roller bearings are also made to Explorer class. SKF Explorer combines our expertise in bearing design, tribology, metallurgy, lubrication and manufacturing. SKF Explorer tapered roller bearings are typically used in bearing solutions where there is a need to increase performance, reduce friction or increase power density in applications.

Spherical roller bearings

Dealing with very heavy radial and axial loads in applications prone to misalignment or shaft deflections can be a real challenge. Meet the challenge with SKF spherical roller bearings. Their high load carrying capacity and ability to accommodate misalignment helps you obtain low maintenance costs and long bearing service life. We offer a wide range of robust spherical roller bearings in both open and sealed variants.

CARB toroidal roller bearings

CARB toroidal roller bearings have one row of long, slightly barrel-shaped symmetrical rollers and torus-shaped raceway profiles (fig. 1). They are non-locating bearings and accommodate exclusively radial loads. CARB bearings are often used to replace the non-locating spherical roller bearing in a locating/non-locating bearing arrangement.

Adapter sleeves

Adapter sleeves are the most commonly used components for locating bearings with a tapered bore onto a cylindrical seat as they can be used on plain shafts (fig. 1) or stepped shafts (fig. 2).

They are easy to install and require no additional location on the shaft. When used on plain shafts, the bearing can be located at any position on the shaft. When used on stepped shafts together with an L-shaped spacer ring, the bearing can be accurately positioned axially, thereby facilitating bearing mounting and dismounting.

Withdrawal sleeves

Withdrawal sleeves can be used to mount bearings with a tapered bore onto the cylindrical seat of stepped shafts (fig. 1). The sleeve is pressed into the bore of the bearing inner ring, which abuts a shaft shoulder or similar fixed component. The sleeve is located on the shaft by a nut or an end plate. KM or HM lock nuts (Lock nuts requiring a keyway) with appropriate locking devices are suitable. Lock nuts are not supplied with the sleeve and must be ordered separately. End plates are not manufactured by SKF.

Lock nuts

Lock nuts are used to locate bearings onto a shaft. Additionally, they can be used to mount bearings with a tapered bore onto tapered shaft seats and adapter sleeves, and to dismount bearings from withdrawal sleeves. Lock nuts are also frequently used to secure gears, belt pulleys and other machine components.

Lock nuts have to be secured to prevent unintentional loosening by:

• a locking device that engages a keyway in the shaft or key slot in the adapter sleeve,
• or a locking mechanism integrated in the nut.

SKF lock nuts provide a variety of ways to secure the nut onto a shaft. The lock nuts listed here constitute the basic SKF assortment. Lock nuts with other locking methods can be supplied on request. For additional information, contact SKF.

SKF industrial lock nuts (table 1)

• requiring a keyway
• with integral locking

SKF precision lock nuts (table 2)

• with integral locking

Lock nuts with integral locking reduce the cost of the shaft as no keyway is required. Installation is quicker and easier because no separate locking device is necessary. However, the loosening torque of these lock nuts requires more attention. For information on loosening torque, refer to the product data sections for the various lock nut series.

Sensor Bearing Units

SKF sensor bearing units are used to monitor accurately the status of rotating or linear components and are compact, robust and reliable, simple and ready-to-mount.

Sensor-integrated solutions engineered by SKF have been well proven in a variety of industrial and automotive applications, such as electric motors, electric vehicles, road rollers, tractors, forklifts and conveyors. Typical uses include:

• motor management

• steering

• speed and position sensing

• measurement of angular position

For additional information about SKF sensor bearing units, contact your local SKF representative.

Hybrid bearings

Hybrid bearings have rings made of bearing steel and rolling elements made of bearing grade silicon nitride (Si3N4), which make the bearings electrically insulating.

Silicon nitride rolling elements can extend bearing service life by offering enhanced bearing performance, even under difficult operating conditions.

INSOCOAT bearings

Electric motors, generators and associated equipment are at risk when an electric current passes through their bearings. This can damage the contact surfaces of rolling elements and raceways in the bearings (electrical erosion) and rapidly degrade the grease. An additional risk in electric motors and generators comes from high frequency currents caused by the inherent stray capacitance. The risk of damage increases where the application uses a frequency converter.

INSOCOAT bearings are designed to prevent electric current from passing through the bearing. The external surfaces of either their inner or outer ring are coated with an insulating aluminium oxide layer, by applying a sophisticated plasma-spray process for an outstanding quality finish. The solutions are very cost-effective compared with other insulation methods.

High temperature bearings and bearing units

SKF high temperature bearings and bearing units are designed to deliver increased reliability, reduced complexity and decreased environmental impact in operating temperatures up to 350 °C (660 °F), making these products very suitable for applications in kiln trucks, roller hearth furnaces, and bakeries. Because SKF high temperature bearings correspond to the ISO dimensions of grease-lubricated bearings, production efficiencies and cost savings can be realized with a simple change to the SKF bearing solution.

NoWear coated bearings

NoWear is a wear-resistant carbon coating that can be applied to the rolling elements and inner ring raceway(s) of a bearing (designation suffix L7DA) or only the rolling elements (designation suffix L5DA) (fig. 1).

A physical vapour deposition process applies the wear-resistant carbon coating. Thickness of the coating ranges from 1 to 3 μm, depending on the size of the bearing. The hardness of the coating is 1 200 HV10.

NoWear coated bearing surfaces retain the toughness of the underlying material while adopting the hardness, improved friction properties and wear-resistance of the coating.

During the running-in period, minute amounts of the coating material are transferred to the counter-surfaces. This coating reduces friction and improves resistance against wear and smearing, even in bearings where only the rolling elements are coated.

Bearings with Solid Oil

SKF bearings with Solid Oil are designed for use in applications where high levels of moisture and incidental contact with water and other contaminants are real issues. Bearings with Solid Oil are lubricated for the life of the bearing and cannot be relubricated.

Solid Oil:

• Is an oil saturated, polymer material moulded into the bearing, forming very narrow gaps between the rolling elements, raceways and cage(s), enabling the bearing to rotate freely
• Having a porous structure, with millions of micro-pores that retain the lubricating oil by surface tension
• Virtually fills all of the free space in the bearing
• Releases oil into the narrow gaps, during operation, providing effective minimum quantity lubrication

With high running accuracy, high-speed performance and high system rigidity, SKF super-precision bearings are ideal for machine tools and other precision applications such as rolling mills, racing cars and marine vessels. The bearings also minimize noise, vibration and heat generation.

With the widest assortment available, you get a choice of bearings to suit your specific performance need. We also offer bearing customization and global access to our application knowledge as well as service centres in 15 countries spread around the world.

Our assortment includes SKF’s trademarked NitroMax steel grade (for certain designs) giving you three times longer service life than standard steel bearings. We also provide hybrid bearings with ceramic rolling elements, particularly suited for high-speed applications.

Slewing bearings comprise an inner ring and an outer ring, one of which usually incorporates a gear. Together with attachment holes in both rings, they enable an optimized power transmission with a simple and quick connection between adjacent machine components. The bearing raceways, in conjunction with the rolling elements and cages or spacers, are designed to accommodate loads acting singly or in combination, and in any direction.

SKF manufactures standard and customized slewing bearings in various designs, with outside diameters from 0,1 to 18 m to meet the demands of particular applications.

For additional information about SKF Kaydon slewing bearings, refer to Kaydon bearings