Single row cylindrical roller bearings with cage
Single row cylindrical roller bearings with cage have a very high radial load carrying capacity and are suitable for high speeds compared to full complement designs. The rollers are guided between rigid ribs in one of the two bearing rings and form a unit with this ring due to the cage. Since a bearing ring of this type can be removed, the rings can be mounted separately. The bearings are available as non-locating NU, N, semi-locating NJ, NF and locating bearings NUP.
Basic design bearings
NPB basic design single row cylindrical roller bearings are available in several designs. The main difference is the configuration of the flanges. The most popular designs (fig.1) are listed in this catalogue and include:
•NU, N design
NU design bearings have two integral flanges on the outer ring and no flanges on the inner ring.
In series N, the bearings have two integral flanges on the inner ring, while the outer ring has no flanges.
These bearings are used as non-locating bearings and can accommodate axial displacement of the shaft relative to the housing in both directions.
• NJ, NF design
NJ design bearings have two integral flanges on the outer ring and one on the inner ring. In series NF, the bearings have two integrated flanges on inner ring, and the outer ring has only one flange.
These bearings are used as semi-locating bearings and support not only high radial forces but also axial force in one direction and therefore guide the shafts axially in one direction.
• NUP, NH design
NUP design bearings have two integral flanges on the outer ring and one integral flange and one non-integral flange i.e. a loose flange ring on the inner ring. Bearings of type NH are combined by the bearing of type NJ and L-section ring for the flangeless side of the inner ring. Comparing to NUP type with short flange ring and non-locating loose flange, type NH can take the advantage of the whole inner ring width of NJ to match with axes tightly. Moreover, it’s quite convenient to mount and dismount.
These type of bearings can support not only high axial forces but also axial forces in both directions and therefore used as locating bearings.
Type of E design
Comparing to the former bearings with the same types, the internal structures have been improved to in order to increase the carrying capacity and life. The bearing code will be suffixed with E.
Bearings without an inner or outer ring
NPB can supply NU design cylindrical roller bearings without an inner ring (RNU series)（fig.4）, and N design bearings without an outer ring (RN series)（fig.3）. These bearings are typically used in applications where hardened and ground raceways are provided on the shaft or in the housing. Because RNU bearings do not have an inner ring, the shaft diameter can be larger to provide a stronger, stiffer shaft arrangement. Additionally, the possible axial displacement of the shaft relative to the housing is limited only by the width of the raceway on the shaft for RNU bearings, or in the housing for RN bearings.
fig.3 fig.4 fig.5 fig.6
Bearings with a snap ring groove
Single row cylindrical roller bearings can be supplied with a snap ring groove in the outer ring (designation suffix N, fig. 6). These bearings can be axially located in the housing by a snap ring to save space and reduce installation time. The dimensions of the snap rings and snap ring grooves are in accordance with GB/T305 （ISO 464）. Check availability prior to ordering.
Bearings with locating slots
When the outer ring must be mounted with a loose fit, bearings with locating slots can be used to prevent the outer ring from turning. Single row cylindrical roller bearings can be supplied with one or two locating slots (designation suffix N1 or N2) in the outer ring ( fig. 5). The two locating slots are positioned 180° apart. The dimensions of the locating slots are in accordance with GB/T27556 （ISO 20515）. Check availability prior to ordering.
Single row full complement cylindrical roller bearings
Full complement cylindrical roller bearings have the maximum possible number of rollers which enable the bearings to have extremely high radial load carrying capacity and high rigidity. Due to the kinematic conditions, however, they do not achieve the high speed that are possible when using cylindrical roller bearings with cage.
• NCF design
NCF design（fig.7） bearings have two integral flanges on the inner ring and one on the outer ring. A retaining ring inserted in the outer ring on the side opposite the integral flange holds the bearing together. The retaining ring should not be loaded axially during operation.
• NJG design
NJG design（fig.8） bearings, which comprise the heavy 23 dimension series, are intended for very heavily loaded, low-speed applications. These bearings have two integral flanges on the outer ring and one on the inner ring. NJG design bearings have a self-retaining roller complement. Therefore, the outer ring with the roller complement can be separated from the inner ring without having to take special precautions to prevent the rollers from falling out. This simplifies mounting and dismounting.