SKF Needle roller / thrust ball bearings combine a radial needle roller bearing and a thrust ball bearing. SKF supplies these bearings in the following two series:
- NX series, a needle roller bearing with a full complement thrust ball bearing
- NKX series, a needle roller bearing with a thrust ball bearing with a cage
SKF supplies the bearings in both series without an inner ring. However, for applications where it is not possible to harden and grind the shaft, the needle roller bearing can be combined with an inner ring. Appropriate inner rings are listed in the product tables and can be ordered separately.
SKF Needle roller / thrust ball bearings, NX series
SKF needle roller / full complement thrust ball bearings in the NX series are suitable for applications where there are moderate radial loads and lighter, single direction axial loads. Their extremely low sectional height enables shaft centrelines to be positioned close together as is the case for multi-spindle drilling machines.
For axial support, the bearings may be mounted against a shoulder or snap ring in the housing bore. The snap ring groove in the outer ring provides a cost-effective and axially spacesaving arrangement.
SKF Needle roller / thrust ball bearings in the NX series have a stamped steel cover that extends over the shaft washer of the thrust ball bearing and is firmly attached to the radial needle roller bearing. These bearings are therefore non-separable. Bearings in the NX series have lubrication holes in the cover and are intended for oil lubrication.
SKF Bearings in the NX .. Z series should be grease lubricated. SKF supplies the thrust ball bearing in this series filled, as standard, with a high-quality grease with good rust inhibiting properties. The cover, which has no lubrication holes, forms a gap-type seal with the shaft washer to retain the grease in the bearing.
SKF Needle roller / thrust ball bearings, NKX series
SKF needle roller / thrust ball bearings in the NKX series combine a radial needle roller bearing and a thrust ball bearing based on the 511 series. They are able to support single-direction axial loads in addition to radial loads. They also permit relatively high-speed operation.
NKX series needle roller / thrust ball bearings do not have a cover around the thrust ball bearing. As a result, both the ball and cage assembly and shaft washer can be mounted separately from the rest of the bearing.
NKX .. Z series SKF needle roller / thrust ball bearings are non-separable. They have a stamped steel cover that extends over the shaft washer of the thrust ball bearing. It is firmly attached to the housing washer that is integral to the needle roller bearing outer ring. The cover makes these bearings non-separable. SKF supplies the thrust ball bearing in this series filled, as standard, with a high-quality grease that has good rust inhibiting properties. The cover, which has no lubrication holes, forms a gap-type seal with the shaft washer to retain the grease in the bearing.
