SKF Needle roller bearings

SKF Needle Bearing with Inner Ring, NA 6903 17x30x23

Needle bearings of types NA 49, NA 69, NKI, and NKIS. Needle bearings with race rings made of rolling bearing steel are low-profile bearings with relatively high load capacity. Bearings with inner rings are suitable for applications where hardening and grinding of the shaft are not possible. They allow axial displacement between the shaft and housing only within certain limits. The bearings with flanges on the outer ring are primarily designed as single-row bearings. In all cases, the outer ring, needle rollers, and cage form a self-contained unit. Bearings of the NA 49 series are also available with sealing rings. This effectively protects the bearings against the ingress of contaminants and the escape of lubricating grease. The inner ring of the sealed bearings is made 1 mm wider and has a lubrication hole. This ensures that the bearings remain effectively sealed even with small axial displacements of the shaft relative to the housing. Main dimensions: ISO 15:2011 / DIN 620:2000 / ISO 1206:2001 / DIN 617:1993 for bearings of the (R)NA 48, (R)NA 49, and (R)NA 69 series.

Prefix: NA 49 / NA 69 Needle bearings with flanges on the outer ring, with inner ring. NKI / NKIS Needle bearings with flanges on the outer ring, with inner ring.

Suffix: 2RS Steel sheet reinforced contact seals made of acrylonitrile-butadiene rubber (NBR) on both sides. TN Glass fiber reinforced cage made of polyamide 66.