NTNNN3017C1PX3P4Double-Row Cylindrical Roller Bearing – Straight Bore, 85 mm ID, 130 mm OD, 34 mm Width, 2 Row, C1 Clearance, P4

Product Description

What this part is

An NTN NN3017-C1-PX3-P4 double-row cylindrical roller bearing. Straight bore 85 mm, outside diameter 130 mm, width 34 mm, open, two rows of cylindrical rollers in machined brass cages, held to P4 super-precision with C1 radial internal clearance.

Decoding the designation

NN marks the double-row cylindrical roller family; 30 is the dimension series and bore code 17 gives 85 mm. C1 is radial internal clearance one grade tighter than C2 — the range used for machine-tool spindles. P4 is ISO class 4, equivalent to ABEC 7.

What these specs mean in practice

Two rows of line-contact rollers give this design far higher radial capacity and far higher radial stiffness than a ball bearing in the same envelope. There are no raceway shoulders working against the rollers axially, so the bearing carries radial load only and provides no axial location; the thrust and axial position of a spindle come from a separate bearing, typically an angular contact pair or a thrust washer set at the other end. C1 clearance and P4 accuracy together hold radial runout very low, which is what keeps a tool or workpiece concentric at speed.

Bore and mounting form

Straight cylindrical bore, mounting on a plain cylindrical journal. Clearance is fixed by the interference of the shaft and housing fits rather than by drive-up on a taper.

Quantity and configuration

One bearing, two roller rows, inner ring, outer ring and cages. 1 Pc.

Fitting notes

The rings of an NN separate: the ribs are on the inner ring and the outer ring lifts off as a plain sleeve, so the two halves are matched at manufacture and are kept as a set. With C1 clearance the shaft and housing fits consume most of the running clearance, so measured seat diameters govern the result more than they do on a normal-clearance bearing. Mounting is by even induction heating of the inner ring.

Interchange guidance

SKF NN 3017 SP, FAG NN3017-AS-M-SP and NSK NN3017TBRE44CC1P4 occupy the same 85 x 130 x 34 mm double-row envelope at super-precision class. Clearance grade is part of the identity: an NN3017 at C2 or CN is a related size rather than a substitute, and a tapered-bore NN3017K mounts on a tapered journal instead of a plain one.