FAG20309TSingle Row Barrel Roller Bearing 45x100x25 mm Polyamide Cage Straight Bore

Product Description

What this part is

A single row barrel roller bearing in the FAG 203xx dimension series, 45 mm bore, 100 mm outside diameter, 25 mm width, with a glass-fibre reinforced polyamide cage. Convex barrel-shaped rollers run in a hollow-ground spherical outer raceway, giving one row of radial capacity together with self-alignment about the bearing’s own centre.

Decoding the designation

In the FAG scheme 203 is the single row barrel roller medium dimension series, and the final two digits are the ISO bore code multiplied by five — 09 reads 45 mm. TVP is the glass-fibre reinforced polyamide cage. Barrel roller bearings in the 202xx and 203xx blocks are a separate family from the double row spherical rollers of the 222xx and 223xx blocks: the spherical outer raceway is shared, the roller profile, row count and thrust behaviour are not.

What these specs mean in practice

A single row of barrel rollers gives high radial load capacity in a shallow section and accommodates misalignment between the shaft seat and the housing bore. Axial capacity is not a property of the design — the barrel roller profile and spherical outer raceway present no shoulder to react thrust — so shaft location is taken by another bearing in the arrangement. The 203xx series is the heavier of the two barrel roller series, so at 45 mm bore this carries a higher radial rating than the corresponding 20209 in the light series.

Cage and temperature

A glass-fibre reinforced polyamide cage is light, quiet and low-friction, and it accelerates and decelerates more readily than a machined brass cage, which favours variable-speed duty. Its continuous operating ceiling is approximately 120 °C, below the range a machined brass cage tolerates, and polyamide is sensitive to ageing in oils containing certain additives at sustained high temperature.

Quantity and configuration

1 Pc. Straight cylindrical bore — no taper, so no adapter sleeve is involved. Open on both faces, with no seals, shields, snap ring or outer ring lubrication groove.

Fitting notes

The straight bore mounts directly to an interference fit on the shaft, by press or by controlled heating of the inner ring within the cage’s temperature limit. The spherical outer raceway absorbs residual misalignment on assembly, so the shaft and housing seats do not require the close alignment a cylindrical roller bearing demands.

Interchange guidance

Other makers’ 20309 barrel roller bearings at the same cage class are the interchange. A 22309 shares the 45 mm bore but is a double row spherical roller, wider, with thrust capability in both directions and a different load rating, so it is a related size rather than a substitution. A 20309M or 20309MB is the same bearing with a machined brass cage: a higher temperature and shock rating, a different speed rating.