SKF Deep groove ball bearings

Deep groove ball bearings are the most widely used bearing type and are particularly versatile. They have low friction and are optimized for low noise and low vibration which enables high rotational speeds. They accommodate radial and axial loads in both directions, are easy to mount, and require less maintenance than other bearing types.

The SKF bearing catalogue lists a large range of designs, variants and sizes of deep groove ball bearings. Beyond our catalogue offering, the SKF Explorer deep groove ball bearings are customizable to offer advantages for applications with specific performance needs.

DESIGNS AND VARIANTS

Single row deep groove ball bearings

Stainless steel deep groove ball bearings

Single row deep groove ball bearings with filling slots

Double row deep groove ball bearings

Product details

Bearing data

Loads

Temperature limits

Permissible speed

Designation system

The seals, which are fitted in a recess on the outer ring, make good, positive contact with the recess, without deforming the outer ring. The capping devices are available as:
Bearing with a snap ring groove

can simplify the design of an arrangement

by locating the bearing axially in the housing by a snap ring

by saving space

by significantly reducing mounting time.

Appropriate snap rings are shown in the product table, along with their designation and dimensions.

The following variants are available

open bearings with a snap ring groove only (designation suffix N)

open bearings with a snap ring (designation suffix NR)

bearings with a snap ring and a shield on the opposite side (designation suffix ZNR)

bearings with a snap ring and a shield on the same side (designation suffix ZNBR)

bearings with a snap ring and a shield on both sides (designation suffix 2ZNR)

SKF Explorer bearings

SKF Explorer rolling bearings accommodate higher load levels and provide extended service life. Optimized internal geometry reduces friction, wear and heat generation, allowing heavier loads to be accommodated. Advanced surface finish reduces friction and enhances lubricating conditions.

Benefits of using SKF Explorer bearings include:

significantly extended service life

increased uptime and productivity

extended lubricant life

reduced sensitivity to misalignment

reduced noise and vibration

enabling downsized applications

SKF Explorer bearings are clearly indicated in the product tables and product detail pages.

For bearing solutions where you want to downsize, reduce vibrations, reduce friction or increase power density in your applications, select SKF Explorer

SKF Quiet Running deep groove ball bearings

Noise and vibration can limit generator reliability

Designed and developed based on the operating conditions of wind turbine generators, SKF Quiet Running bearings help prevent resonance that can occur between the rotor, stator and bearings. Less sensitive to variable wind turbine operating conditions such as changing wind speeds, SKF Quiet Running bearings can increase bearing service life and extend relubrication intervals. 

Benefits

Minimizes structural resonance and vibration levels 

Reduces noise emissions  

Increases service life thanks to better grease utilization  

Improves overall system reliability  

100% interchangeable with conventional bearings  

Available with pressed steel or machined brass cages  

These benefits are possible thanks to a specific design and manufacturing process which results in very low level of noise and vibration. Reduced vibration has a direct impact on the fatigue of the whole system and can lead to increased system reliability and life. The lower noise level helps to reduce overall turbine emissions, and thereby makes it easier to comply with allowance criteria for wind projects. 

Additionally, they are equipped with a new set of cages that can have a significant positive impact on grease life. The full interchangeability with existing deep groove ball bearings make SKF Quiet Running bearings a plug and play solution. 

Matched bearings

are used where the load carrying capacity of a single bearing is inadequate

are used where the shaft has to be located axially in both directions with a specific axial clearance

where mounted immediately adjacent to each other, distribute the load between the bearings without having to use shims or similar devices

A 'V-shaped' marking on the outside surface of the outer rings of matched bearings  indicates how the pair should be mounted. The bearing pairs are supplied as a packaged unit.

Matched pairs can be supplied in three different arrangements

Tandem arrangement

is identified by the designation suffix DT

is used where the load carrying capacity of a single bearing is inadequate

has parallel load lines and therefore shares the radial and axial loads equally

can accommodate axial loads in both directions

Back-to-back arrangement

is identified by the designation suffix DB

has load lines that diverge towards the bearing axis

provides a relatively stiff bearing arrangement

can accommodate tilting moments

can accommodate axial loads in both directions, but only by one bearing in each direction

Face-to-face arrangement

is identified by the designation suffix DF

has load lines that converge towards the bearing axis

is less sensitive to misalignment but not as stiff as a back-to-back arrangement

can accommodate axial loads in both directions, but only by one bearing in each direction

Cage
The main cage types are described in Components and materials. Additionally, information about standard cages, and possible cage options, for a particular bearing type is given in the relevant product section. If a bearing with a non-standard cage is required, check availability before ordering.

There are fundamental design differences between bearings which, together with the influence of bearing size, make certain cage designs necessary. For example:

some bearing types need either split or snap-type cages, because they are assembled after the rings and rolling elements have been sub-assembled

other bearing types need roller-guided cages, to be self-containing

bearings of a certain combination of size and series need ring-guided cages, to limit contact stress between rolling elements and cage.

Given the specific functional demands and quantity of bearings being manufactured, the material and manufacturing methods are chosen to provide the most reliable and cost-effective cage.

Cages are mechanically stressed during bearing operation by frictional, impact, centrifugal and inertial forces. They can also be chemically influenced by certain organic solvents or coolants, lubricants, and lubricant additives. Therefore, the material type used for a cage has a significant influence on the suitability of a rolling bearing for a particular application.

Steel cages

Steel cages can be used at operating temperatures up to 300 °C (570 °F).

Sheet steel cages

Stamped sheet steel cages are made of low carbon steel. These lightweight cages have relatively high strength and, for some bearing types, can be surface treated to further reduce friction and wear in critical conditions.

Machined steel cages

Machined steel cages are normally made of non-alloyed structural steel. To reduce friction and wear, some machined steel cages are surface treated.

Machined steel cages are not affected by the mineral or synthetic oil-based lubricants normally used for rolling bearings, or by the organic solvents used to clean bearings.

Brass cages

Brass cages can be used at operating temperatures up to 250 °C (480 °F).

Sheet brass cages

Stamped sheet brass cages are used for some small and medium-size bearings. In applications such as refrigeration compressors that use ammonia, machined brass or steel cages should be used.

Machined brass cages

Most brass cages are machined from cast or wrought brass. They are unaffected by most common bearing lubricants, including synthetic oils and greases, and can be cleaned using organic solvents.

Polymer cages

Polyamide 66

Polyamide 66 (PA66) is the most commonly used material for injection moulded cages. This material, with or without glass fibres, is characterized by a favourable combination of strength and elasticity. The mechanical properties, such as strength and elasticity, of polymer materials are temperature dependent and subject to ageing. The factors that most influence the ageing process are temperature, time and the medium (lubricant) to which the polymer is exposed. . Cage life decreases with increasing temperature and the aggressiveness of the lubricant.

Therefore, whether polyamide cages are suitable for a specific application depends on the operating conditions and life requirements. The classification of lubricants into “aggressive” and “mild” is reflected by the “permissible operating temperature” for cages made of glass fibre reinforced PA66 with various lubricants..

 A typical example is ammonia, used as a refrigerant in compressors. In those cases, cages made of glass fibre reinforced PA66 should not be used at operating temperatures above 70 °C (160 °F).

Polyamide loses its elasticity at low temperatures. Therefore, cages made of glass fibre reinforced PA66 should not be used in applications where the continuous operating temperature is below –40 °C (–40 °F).

Polyamide 46

Glass fibre reinforced polyamide 46 (PA46) is the standard cage material for some small and medium-size CARB toroidal roller bearings. The permissible operating temperature is 15 °C (25 °F) higher than for glass fibre reinforced PA66.

Polyetheretherketone

Glass fibre reinforced polyetheretherketone (PEEK) is more suitable for demanding conditions regarding high speeds, chemical resistance or high temperatures than PA66 and PA46. The exceptional properties of PEEK provide a superior combination of strength and flexibility, high operating temperature range, and high chemical and wear resistance. Because of these outstanding features, PEEK cages are commonly available for hybrid and/or super-precision ball and cylindrical roller bearings. The material does not show signs of ageing by temperature or oil additives up to 200 °C (390 °F). However, the maximum temperature for high-speed use is limited to 150 °C (300 °F) as this is the softening temperature of the polymer.

Cages made of other materials

In addition to the materials described above, SKF bearings for special applications may be fitted with cages made of other engineered polymers, light alloys or special cast iron. For additional information about alternative cage materials, contact SKF.