NSK22228EJW33Spherical Roller Bearing – 140 mm ID, 250 mm OD, 68 mm Width, Double Row, Straight Bore, Open, W33 Lubrication Groove, CN Internal Clearance.

Product Description

What this part is

A double-row spherical roller bearing in the ISO 222 dimension series, with an outer ring lubrication groove and radial feed holes. Bore Diameter: 140 mm. Outside Diameter: 250 mm. Overall Width: 68 mm. Rolling Elements: Spherical Roller. Number Of Rows: 2. Bore Type: Straight. Closure Type: Open. Cage Material: Pressed steel. Cage Type: Pressed steel, centred on the inner ring and rollers. Internal Clearance: CN. Bearing Material: Bearing steel.

Decoding the designation

222 — spherical roller bearing, double row, ISO 222 dimension series. The outer ring raceway is a single sphere, so the roller rows align themselves to it.

28 — the bore code. Bore Diameter: 140 mm.

E — the high-capacity steel-cage design. The roller complement and raceway profile are revised upward from the base design at the same envelope.

J — pressed steel cage, centred on the inner ring and the rollers.

W33 — a lubrication groove machined around the outer ring with three radial holes through to the raceway. The groove distributes lubricant around the outer ring and the holes carry it inward to the rollers. Lubricant: Grease or oil.

What these specs mean in practice

Dynamic Load Rating: 822,000 N. Dynamic Load Rating (lbf): 184,793 lbf. Static Load Rating: 1,080,000 N. Static Load Rating (lbf): 242,795 lbf. Limiting Speed: 1,700 rpm grease; 2,200 rpm oil.

On a double-row spherical roller the static rating sits above the dynamic rating. Two long rollers per row share a large contact area, so the load that would permanently indent a raceway is high relative to the load that sets fatigue life.

The spherical outer raceway absorbs shaft deflection and mounting misalignment without edge-loading the raceway, which is why this type is used on long shafts and in split housings.

Mounting data

Bore Diameter: 5.5118 in. Outside Diameter: 9.8425 in. Overall Width: 2.6772 in. Bore Type: Straight, so the inner ring mounts directly on a cylindrical shaft seat with no adapter sleeve. Relubrication Feature: Yes, through the W33 groove and its three radial holes. Snap ring included: No.

Quantity and configuration

Unit Quantity: 1 Pc.

Interchange guidance

The 140 by 250 by 68 mm envelope with a W33 groove is the standard ISO 22228 size. The crosses listed share that envelope, the double-row spherical form and the W33 feature; cage execution and load rating vary between makers’ designs.