Table
Ball bearing designations
Deep groove ball bearings 6000, 6200 and 6300 with dimensions to DIN 625, the bore code explained and the meaning of the suffixes 2RS, 2Z, C3 and the like.
A bearing number such as 6204-2RS C3 is a code: 62 is the series, 04 the bore code (times 5 = 20 mm), 2RS the seal, C3 the bearing clearance. The bearing decoder breaks down any number automatically.
| Bearing | Bore d mm | Outside D mm | Width B mm |
|---|---|---|---|
| 6000 | 10 | 26 | 8 |
| 6001 | 12 | 28 | 8 |
| 6002 | 15 | 32 | 9 |
| 6003 | 17 | 35 | 10 |
| 6004 | 20 | 42 | 12 |
| 6005 | 25 | 47 | 12 |
| 6006 | 30 | 55 | 13 |
| 6200 | 10 | 30 | 9 |
| 6201 | 12 | 32 | 10 |
| 6202 | 15 | 35 | 11 |
| 6203 | 17 | 40 | 12 |
| 6204 | 20 | 47 | 14 |
| 6205 | 25 | 52 | 15 |
| 6206 | 30 | 62 | 16 |
| 6300 | 10 | 35 | 11 |
| 6301 | 12 | 37 | 12 |
| 6302 | 15 | 42 | 13 |
| 6303 | 17 | 47 | 14 |
| 6304 | 20 | 52 | 15 |
| 6305 | 25 | 62 | 17 |
| 6306 | 30 | 72 | 19 |
Suffixes
| Suffix | Meaning |
|---|---|
| 2RS / 2RSR / 2RSH | contact rubber seals on both sides; good against dirt, slightly more friction |
| RS | seal on one side |
| 2Z / ZZ | sheet steel shields on both sides, non-contact; for clean surroundings, low friction |
| Z | shield on one side |
| 2RZ / LLB / VV | non-contact rubber seal on both sides (SKF / NTN / NSK) |
| C2 | bearing clearance smaller than normal |
| CN (no suffix given) | normal bearing clearance |
| C3 | bearing clearance greater than normal; standard on crankshafts and hot engines, because the inner ring expands more |
| C4 / C5 | large and very large bearing clearance respectively |
| N / NR | groove in the outer ring / with circlip |
| TN / TN9 / TVH | polyamide cage (glass fibre reinforced) |
| M / MA | solid brass cage |
| J | pressed steel cage |
| P5 / P6 | higher precision class |
| HT / LHT | high temperature and wide range grease respectively |
| W / S | stainless steel (prefix) |
Bore code
The last two digits: 00 = 10 mm, 01 = 12 mm, 02 = 15 mm, 03 = 17 mm. From 04 upwards the code is multiplied by 5: 04 = 20 mm, 05 = 25 mm, 06 = 30 mm.
C3 on the crankshaft
Engine bearings run hot. The inner ring on the shaft expands more than the outer ring in the housing, so the bearing clearance shrinks in operation. That is why C3 bearings have more clearance when cold and run warm with normal play. A CN bearing on the crankshaft becomes too tight in operation and dies early. How to change crankshaft bearings is explained under changing crankshaft bearings.
Questions
What does 2RS mean?
Contact rubber seals on both sides. Good against dirt, slightly more friction. Suitable for wheel bearings; on crankshafts in an oil mist, open bearings or 2Z are usual.
Can I replace C3 with a normal bearing?
In cold places such as wheel hubs, yes. On the crankshaft and the gearbox input, no: there C3 is a deliberate choice.