Deep groove ball bearings are used in various applications because they have a simple structure,they are not separable, suitable for very high speeds and have modest requirements for what concerns the duration of the exercise and the maintenance. These bearings are ideal for medium axial loads in one or both directions and are available in different variants of insulations and lubrication for all services conditions. The series of this bearings are the following : 600, 60…, 62.., 63…, 64.., 16.. ; while bearings with thinsection rings are : 61800 and 61900. ITS Italia produces deep groove ball bearings in various designs and sizes.Deep groove ball bearings are produced with normal internal clearance (CN) as standard. The values of standard internal clearance are defined in such a way that bearings with CN clearance will have sufficient residual operating clearance when mounted using “normal” bearing fits.
Single row deep groove ball bearings
Single row deep groove ball bearings are the most commonly used rolling bearings. The balls run in deep grooves in both the outer and inner rings. This enables the bearing type to accommodate radial loads as well and some axial loads in either direction. These bearings have a simple structure,they are not separable. Deep groove ball bearings have many play classes and tolerances for different service condition and they are suitable for high speed applications due to their low friction. They achieve the highest speed ratings of a rolling bearings types. Deep groove ball bearings are available in a wide variety of designs with different shields and seals. These bearings with shields or seals are lubricated for life and they are maintenance free. These bearings can be supplied open, that is without seals and submit grooves in the outer ring to support the seals. These bearings should not be washed or heated to temperatures above 80 °C. Single row deep grooved ball bearings are produced to normal tolerance class (PN), as standard. Application of higher dimensional and geometrical accuracy the bearings are produced to precision tolerance classes P6 a p5. Single row deep groove ball bearings have a very limited ability to accommodate misalignment. Under normal application conditions, misalignment may not exceed 10 angular minutes maximum from their centre position. In must be considered that bearings which run misaligned are subjected to considerable additional forces that will shorten their service life and generate high running noise.
Deep groove ball bearings with special grease filling
For special operating conditions these bearings can also be supplied with special grease fillings according to customer’s specification or with grease fill volumes other than the standard.
ITS Italia produces various types of single deep groove ball bearings :
– bearings with tapered bore
– stainless steel bearings
– high temperature bearings
– inch bearings
– thin section bearings
– micro bearings
– flanged bearings
These bearings are also available with a groove for anchoring ring, that is they can be hold in the axial direction in the housing by an anchor ring,ensuring a space-saving. These bearings can be supplied in the following versions:
➔without seals, that are “open” , identify with letter “N”
➔open with anchor ring , identify with letters “NR”
➔with shield “ZZ” on both sides and anchor ring , identify with initials “2ZNR”
➔with shield ” Z ” in the opposite side and anchor ring, identify with letters”ZNR”.
Shields represent the most simple form of sealing. The shields are sheet metal shims press fitted into the outer ring groove profile on either one side ( suffix -Z ) or on both sides ( suffix -ZZ). Protections are made of sheet steel During operation a collar of grease may develop around the inner ring outside diameter providing some prevention against contaminate penetration, although grease loss is possible for applications where the outer ring rotates at high speed. In the case of ZZ- shielded bearings that operate with their outer ring rotating, the maximum operating speed must not exceed 40% of the recommended limited speed ratings.
Seals form a rubbing contact seal between the bearings inner and outer ring. Depending upon the bearing design, type and size they are produced with single-lip seal ( RS) , or with double lips and the labyrinth in the inner ring ( RS2). If seals are present in both sides are indicated with suffix 2RS or 2RS2. These contacting seals are produced using a wear resistant synthetic rubber (NBR) and are suitable for operating temperatures from -30°C to +120°C. The seals have integrated steel washers to increase their rigidity. For special applications, however, seals are also available in other materials.
In the case of purely axial loaded bearings the acting thrust forces must not exceed certain limits. The limits are determined by the internal bearing design.