ConsolidatedNJ-411 MSingle-Row Cylindrical Roller Bearing 55 x 140 x 33 mm, NJ Design, Straight Bore, Machined Brass Cage, Locates in One Direction

Product Description

What this part is:

A Consolidated NJ 411 M single-row cylindrical roller bearing, 55 mm bore x 140 mm outside diameter x 33 mm wide, straight bore, with a machined brass cage. This is ISO dimension series 4 — an unusually heavy section for the bore, giving 142 kN dynamic radial capacity on a 55 mm shaft in a 42.5 mm cross-section. Consolidated Bearings is a US brand that sources European manufacture, and SRO is the maker’s marking carried on this unit.

Decoding the designation:

• NJ — single row with two ribs on the outer ring and one rib on the inner ring. The bearing locates the shaft axially in one direction.
• 4 — ISO dimension series 4, the heavy section.
• 11 — 55 mm bore.
• M — machined brass cage.
• NH411 — the designation for this bearing supplied together with an HJ411 loose angle ring. An NH combination locates the shaft in both directions; an NJ on its own locates in one.
• Bore form: straight cylindrical.

Axial location and the NJ, NH, NU and NUP designs:

Rib arrangement is the specification a cylindrical roller bearing is selected on, and these designs are not interchangeable:

• NJ — one inner-ring rib. Takes light axial load and locates the shaft in one direction. This bearing.
• NH — an NJ plus a separate HJ angle ring on the open side. Locates the shaft in both directions.
• NUP — two inner-ring ribs, one a loose flange ring, achieving two-direction location in a single order code.
• NU and N — no inner-ring rib and no outer-ring rib respectively. Both are non-locating and allow the shaft to move axially through the bearing.

All of these share the 55 x 140 x 33 mm envelope and the same radial rating, so the rib arrangement is what decides whether the shaft is located, and in how many directions.

Quantity and configuration:

Sold as 1 Pc — one complete bearing: the twin-ribbed outer ring, and the inner ring with its single rib carrying the roller and brass cage assembly. The HJ411 angle ring is not included. With the angle ring fitted this bearing becomes the NH411 arrangement; as supplied it is the NJ411.

What these specs mean in practice:

Line contact between roller and raceway is what buys the load capacity: a cylindrical roller spreads its load along a line rather than a point, giving several times the radial rating of a ball bearing on the same shaft, at the cost of a lower speed ceiling and no meaningful thrust capacity. The series-4 section puts an unusually large roller set on a 55 mm bore, which is why this size appears in heavily loaded, slow-turning positions rather than high-speed ones.

A machined brass cage suits heavy loads, shock loading, high temperature and oil lubrication, and tolerates conditions that break down a pressed-steel or polyamide cage.

Published ratings and mounting data:

• Bore d: 55 mm (2.1654 in) — Outside diameter D: 140 mm (5.5118 in) — Width B: 33 mm (1.2992 in)
• Basic dynamic load rating C: 142 kN (ISO NJ411 envelope)
• Basic static load rating C0: 140 kN
• Rows: 1 — rolling element: cylindrical roller
• Bore form: straight cylindrical
• Rib arrangement: two outer-ring ribs, one inner-ring rib (NJ)
• Cage: machined brass
• Radial internal clearance: normal (CN) — no clearance suffix in the designation
• Closure: open, no seals or shields
• Material: through-hardened bearing steel
• Separable: the inner ring with its roller set parts from the outer ring

Fitting notes:

The inner ring goes on with an interference fit, heated or pressed square to the shaft shoulder, with the ribbed inner-ring face oriented to take thrust in the direction the arrangement requires — that orientation is what makes the NJ design do its job. The outer ring seats in the housing bore to the fit the drawing calls for. Because the rings separate, they mount independently, and each ring is marked so the roller assembly returns to its original outer ring.

Interchange guidance:

Same-specification equivalents at 55 x 140 x 33 mm with the NJ rib arrangement and a machined brass cage: SKF NJ 411 M, NSK NJ411W, NTN NJ411, FAG NJ411-M1, Koyo NJ411, NKE NJ411-M. Related sizes, not substitutes: NU411, N411 and NUP411 share this envelope but carry their ribs differently and behave differently axially; NH411 is this bearing plus the HJ411 angle ring; NJ311 and NJ211 are the series-3 and series-2 bearings on the same 55 mm bore with smaller outside diameters and lower ratings; a pressed-steel-cage NJ411 has a lower temperature and shock ceiling than this brass-caged unit.