FAG20312MBSingle-Row Barrel Roller Bearing – 60 mm ID, 130 mm OD, 31 mm Width, Self-Aligning, Machined Brass Cage

Product Description

What this part is

FAG 20312-MB single-row barrel roller bearing. Bore Diameter: 60 mm. Outside Diameter: 130 mm. Overall Width: 31 mm. Rolling Elements: Barrel Roller. Number Of Rows: 1. Bore Type: Straight. Closure Type: Open. Cage Material: Machined brass. Cage Type: Machined. Precision Class: RBEC 1 / P0. Internal Clearance: CN. Bearing Material: Chrome steel. Series: 203. Base Number: 20312. Unit Quantity: 1 Pc.

Decoding the designation

203 — single-row barrel roller bearing to DIN 635-1. One row of convex barrel-shaped rollers runs on a spherical raceway ground into the outer ring, so the inner ring and roller set swivel inside the outer ring.

12 — bore code. Bore Diameter: 60 mm.

MB — one-piece machined brass cage. Brass handles high temperature, shock loading and marginal lubrication better than a polyamide cage, and it is the execution chosen where the operating temperature runs above the range of a plastic cage.

Searchable forms of the designation: 20312MB, 20312-MB, 20312 MB, 20312M, 20312.

What these specs mean in practice

The spherical outer raceway lets the bearing take shaft-to-housing misalignment and shaft deflection without edge-loading the rollers. That is why a barrel roller is chosen for long shafts, fans, conveyor pulleys and vibrating screens.

A single row of barrel rollers carries heavy radial load. Axial location comes from a separate bearing in the arrangement.

A barrel roller bearing is self-aligning and has no contact angle.

Bore Type: Straight. The inner ring seats directly on a parallel shaft journal.

Mounting data

Bore Diameter: 60 mm, straight. Outside Diameter: 130 mm. Overall Width: 31 mm. Shaft shoulder diameter da 72 mm minimum. Housing shoulder diameter Da 118 mm maximum. Maximum recess radius ra 2.1 mm. Minimum chamfer dimension r 2.1 mm. Outer ring bore diameter D1 111.2 mm.

Quantity and configuration

Unit Quantity: 1 Pc. One complete bearing, open on both faces.

Interchange guidance

Cross-Reference 1: FAG 20312-TVP (related, glass-fibre polyamide cage on the same envelope). Cross-Reference 2: SKF 20312. Cross-Reference 3: Consolidated 20312-M. Cross-Reference 4: FAG 20312-K-TVP (related, 1:12 tapered bore for an adapter sleeve).

All four share the 60 x 130 x 31 mm envelope to DIN 635-1. Barrel roller bearings are built by a short list of makers, so a nine-way interchange does not exist for this type; the references above are the genuine ones.