Cylindrical Roller Bearings

The cylindrical roller bearings have greater radial load capacity than ball bearings of same external dimensions and are particularly suitable for arduous duties. The roller bearings feature a modified line contact between rollers and raceways to eliminate edge stressing. These bearings have a high radial load capacity and are suitable for high speeds. Due to detachable design character they have advantage of mounting inner ring and outer ring separately. The direction of axial load which a bearing can take depends upon the geometry of the bearing.

DOUBLE ROW (CRB)

FOUR ROW (CRB)

FULL COMPLEMENTARY

SINGLE ROW (CRB)

THRUST CYLINDRICAL ROLLER

Cylindrical roller bearings use rollers as rolling elements, and therefore have a higher load capacity in comparison to same dimension ball bearing. The rollers are guided by the ribs of the inner or outer ring. The inner and outer rings can be separated to facilitate assembly, and both can be fit with shaft or housing tightly. If there are no ribs, either the inner or the outer ring can move freely in the axial direction. Cylindrical roller bearings are therefore ideal to be used as so-called “free side bearings” that absorb shaft expansion. In the case where there is a rib, the bearing can bear a slight axial load between the end of the rollers and the rib. Cylindrical roller bearings include the ‘HT’ type which incorporates the modified shape of roller end face and ribs for increasing axial road capacity. And the ‘E’ type with a special internal design for enhancing radial load capacity. The E type is standardized for small-diameter sizes.


NU design:

The outer ring has two integral flanges while the inner ring has no flanges. Axial displacement of the shaft with respect to the housing can be accommodated in both directions.


N design:

The inner ring has two integral flanges while the outer ring has no flanges.Axial displacement of the shaft with respect to the housing can be accommodated in both directions.


Nj design:

The outer ring has two integral flanges while the inner ring has one integral flange. These bearings can locate the shaft axially in one direction only.


Nup design:

The outer ring has two integral flanges while the inner ring has one integral flange and one loose flange ring. These bearings can be used as locating bearings to locate the shaft axially in both directions.


Rnu design:

NU-design cylindrical roller bearings without an inner ring.


Nh design:

These are designed to stabilize NU- and NJ-type cylindrical roller bearings in the axial Direction.

NBC manufactures double row cylindrical roller bearings with both cylindrical bore and tapered bore.

Double Row Cylindrical Roller Bearings are widely used for applications requiring thin-walled bearings, such the main shafts of machine tools, rolling machine rollers, and in printing equipment. Internal radial clearance is adjusted for the spindle of machine tools by pressing the tapered bore of the inner ring on a tapered shaft.

The bearing components of Double Row CRBs can be mounted separately, facilitating efficient mounting, inspection and maintenance of these bearings.

NBC produces Four Row Cylindrical roller bearings in different designs and arrangements depending on the requirement of the application.

The variations are based on number of inner and outer rings, number of loose or integral flanges on the outer ring/ inner ring and type of cage design.

Four Row Cylindrical roller bearings are mainly used in the necks of rolling machine rollers – they are designed for maximum rated load to accommodate the severely limited space in the roller neck section of such equipment. In the event of a requirement where the bearings are mounted with a loose fit on the roll neck, the bearings are made with helical grooves in the bore or lubrication grooves in the side faces of the bearing rings so that the mating surfaces are efficiently lubricated.

Full complement cylindrical roller bearings integrate a maximum number of rollers without the usage of any cage and are therefore suitable for very heavy radial loads. However, they cannot operate at the same high speeds as caged design cylindrical roller bearings.

These bearings provide an average radial load rating increase of 20 percent and a life increase of 80 percent.

Thrust bearings incorporating cylindrical rollers are available in single row, double row Cylindrical roller thrust bearings are able to receive axial loads only, and have high axial rigidity which makes them well suited for heavy axial loads. Bearings with dimensions not listed in the dimension tables are also manufactured. Contact NBC for more information.