FAGCylindrical Roller Bearing – 45 mm ID, 100 mm OD, 25 mm Width, NU Non-Locating Design, Machined Brass Cage, ABEC 3 / P6

Product Description

What this part is

FAG NU309-M1-P6 single-row cylindrical roller bearing. Bore Diameter: 45 mm. Outside Diameter: 100 mm. Overall Width: 25 mm. Rolling Elements: Cylindrical Roller. Number Of Rows: 1. Bore Type: Straight. Closure Type: Open. Cage Material: Machined brass. Cage Type: Machined. Precision Class: ABEC 3 / P6. Bearing Material: Chrome steel. Series: NU3. Base Number: NU309. Unit Quantity: 1 Pc.

Decoding the designation

NU — two integral ribs on the outer ring, a plain inner ring with no ribs. The rings separate, and the bearing is a non-locating position: the shaft is free to move axially relative to the housing inside the roller set.

3 — ISO dimension series 03, the medium section. 09 — bore code. Bore Diameter: 45 mm.

M1 — one-piece machined brass cage, inner-ring guided. Brass tolerates high speed, shock loading and elevated temperature better than pressed steel or polyamide.

P6 — tolerance class P6, equivalent to ABEC 3. Tighter bore, outside diameter and running accuracy than a standard P0 bearing.

Searchable forms of the designation: NU309M.P6, NU309-M-P6, NU309MP6, NU-309-M-P6, NU309M1P6, NU309.

What these specs mean in practice

A cylindrical roller carries far more radial load than a ball in the same envelope, because the roller meets the raceway along a line rather than at a point.

The NU form takes no axial load at all. It is the free end of a two-bearing arrangement, with a separate locating bearing setting the shaft position, and it absorbs thermal growth of the shaft without building an axial force.

Precision Class: ABEC 3 / P6 buys closer bore and outside-diameter tolerance and lower radial runout, which shows up as less spindle vibration and better location under load.

A cylindrical roller bearing has no contact angle.

Mounting data

Bore Diameter: 45 mm, straight. Outside Diameter: 100 mm. Overall Width: 25 mm. Shaft shoulder diameter da 54 mm minimum to 57 mm maximum. Housing shoulder diameter Da 91 mm maximum. Minimum chamfer dimension r 1.5 mm, maximum recess radius ra 1.5 mm. Both rings take an interference fit and are mounted separately.

Quantity and configuration

Unit Quantity: 1 Pc. One complete bearing: outer ring with roller and cage assembly, plus the plain inner ring.

Interchange guidance

Cross-Reference 1: SKF NU 309 ECM/P6 (E design, P6 class). Cross-Reference 2: FAG NU309-E-XL-M1 (current E-XL design, not P6). Cross-Reference 3: NSK NU309M (not P6). Cross-Reference 4: NTN NU309G1 (not P6). Cross-Reference 5: Timken NU309EMA (E design, not P6). Cross-Reference 6: RHP NU309M (not P6). Cross-Reference 7: Koyo NU309 (class and cage not specified). Cross-Reference 8: SNR NU309EG15 (E design, not P6). Cross-Reference 9: Nachi NU309 (class and cage not specified).

All are NU309 non-locating parts in the 45 x 100 x 25 mm envelope. Check the precision class and cage before substituting.