SKF6211-2RS1Deep Groove Ball Bearing, Contact Seals Both Sides, 55 x 100 x 21 mm — Greased for Life

Product Description

What this part is

An SKF deep groove ball bearing, the most widely used bearing type there is: 55 mm bore, 100 mm outside diameter, 21 mm wide, with rubber contact seals on both faces. One row of balls in deep circumferential grooves, carrying radial load and moderate thrust in both directions from a single bearing. It is the default choice for electric motors, pumps, fans, gearboxes, conveyor idlers and general machinery, and the 6200/6300 series numbering is understood by every maintenance department in the world.

Decoding the designation — 2RS1 is a seal, not a shield:
62: deep groove ball bearing, 62 dimension series.

11: bore code, 55 mm.

2RS1: contact seals on both sides in SKF’s scheme. RS denotes a rubbing (contact) seal; the 1 identifies the seal design; the leading 2 means both sides. The single-seal version is RS1.

The distinction that matters is 2RS1 versus 2Z. A 2Z bearing has sheet-metal shields: they run with a small clearance to the inner ring and never touch it. A 2RS1 bearing has contact seals: the rubber lip rubs on the inner ring land.

Sealed or shielded — the decision that actually matters here:
This is the choice that determines whether the bearing survives in a given application, and the two builds share the same part number apart from the suffix.

Contact seals, as on this bearing, genuinely exclude water, fine dust, coolant mist and washdown spray, and they retain grease under pressure. Nothing gets in and the grease does not get out. In a wet, dusty, food-plant or outdoor position, a sealed bearing lasts and a shielded one does not. Because the seal is a positive barrier, the bearing is greased for life and needs no lubrication port in the housing at all, which is a real simplification when designing or repairing a bearing housing.

The cost is friction and speed. The rubbing lip generates drag and heat, so a 2RS1 bearing runs measurably slower and hotter than the 2Z equivalent. On a high-speed motor shaft that penalty is significant; on a conveyor idler or a fan hub it is irrelevant.

The corollary to know: grease pumped into a housing will not reach a 2RS1 bearing. The seal is doing its job. Where a relubrication schedule exists, an open or shielded bearing is the correct specification.

Published dimensions

Bore (d): 55 mm.

Outside diameter (D): 100 mm.

Width (B): 21 mm.

Closure: contact seals both sides (2RS1).

Bore type: straight (cylindrical).

Internal clearance: normal. The looser build is 6211-2RS1/C3.

Number of rows: 1.

Rolling elements: steel balls, single row.

Relubrication: greased for life.

Quantity and configuration

One bearing, sold individually. Most shafts run two deep groove bearings, one at each end, so a pair is the natural order quantity and keeps both ends of a shaft on matched new bearings.

Interchange guidance

Search forms include 6211-2RS1, 6211-2RS, 62112RS1, 6211 2RS1, 6211RS, 6211-2RSR, 6211-2RS1/C3, 6211. Related SKF builds at the same envelope: 6211-2Z (shields both sides, a different closure, faster, and not weatherproof), 6211 (open), 6211-2RS1/C3 (C3 clearance), 6211-RS1 (one seal). The legacy designations 211 and 211 PP describe the same 55 × 100 × 21 mm envelope and appear on older drawings. Same-envelope equivalents: FAG 6211-2RSR, NSK 6211DDU, NTN 6211LLU, Koyo 6211-2RS, Nachi 6211-2NSE. The 6311-2RS1 is a different bearing — also 55 mm bore, but 120 mm outside diameter and 29 mm wide. Check the outside diameter, not just the bore.