Mounting dimensions — chamfer, shaft shoulder and housing shoulder (with one known data defect)
2026-10-31
The four mounting-related columns, their measured values across 100 models, how large the shoulder clearances are, and the one row we have confirmed is wrong.
Fitting a deep groove ball bearing comes down to four dimensions: chamfer r, shaft shoulder da min, housing shoulder Da max, and fillet ra max. This page explains how to use them, the values our catalogue actually carries, and one row we have confirmed is wrong.
Only four mounting columns exist
Chamfer r min
The minimum chamfer at the ring edge. It sets the largest fillet your shaft shoulder and housing shoulder may have — if your shoulder fillet is larger than this, the bearing will not seat against the shoulder face.
Shaft shoulder da min
The minimum supporting diameter at the shaft shoulder (or adapter sleeve). Below it, the inner ring face is not properly supported.
Housing shoulder Da max
The maximum diameter of the housing shoulder (the bore step). Above it, the outer ring face is not properly supported.
Fillet ra max
The maximum fillet radius allowed on the shaft and housing shoulders.
⚠️ An easy detail to miss: in all 700 rows of this table, ra max carries exactly the same number as r min (700/700). So our ra max is not a separate measurement — it is the same figure as the chamfer. Treat it as the concrete number for the rule "the mating fillet must not exceed the bearing chamfer".
Measured values
All four columns are complete on all 100 models
Across the 100 open-type rows, r, da min, Da max and ra max all have values — not a single blank.
Chamfer distribution (open-type rows):
| r (mm) | Models |
|---|---|
| 0.15 | 3 |
| 0.2 | 5 |
| 0.3 | 46 |
| 0.6 | 16 |
| 1.0 | 13 |
| 1.1 | 8 |
| 1.5 | 5 |
| 2.0 | 2 |
| 2.1 | 1 |
0.3 mm accounts for half — small-bore models dominate, and their chamfers are naturally small.
How large are the shoulder clearances
Measured on open-type rows (excluding 6209, see below):
da min − d: 0.8 – 12.0 mmD − Da max: 0.8 – 12.0 mm
Both ranges end exactly at 0.8 and 12.0, so the two clearances are symmetrically designed across the catalogue: inner and outer ring each give up the same allowance.
Some concrete cases (mm):
| Model | d | D | r | da min | Da max | ra max |
|---|---|---|---|---|---|---|
| 605 | 5 | 14 | 0.2 | 6.4 | 12.6 | 0.2 |
| 6000 | 10 | 26 | 0.3 | 12.0 | 24.0 | 0.3 |
| 6205 | 25 | 52 | 1.0 | 30.6 | 46.4 | 1.0 |
| 6305 | 25 | 62 | 1.1 | 32.0 | 55.0 | 1.1 |
| 6312 | 60 | 130 | 2.1 | 72.0 | 118.0 | 2.1 |
🔴 One known data defect: 6209
6209 lists Da max as 88 mm, but its outer diameter D is only 85 mm.
A housing shoulder larger than the outer ring is physically impossible, so that figure is certainly wrong. All seven seal variants of this model carry it — seven rows in total.
We have not corrected the number ourselves: the parameter table is the factory's single source, and editing it would make the figure ours rather than theirs. That cell is currently unusable. If you need 6209 shoulder dimensions, ask us directly (contact us) and we will answer from the factory's own data.
Every statistic above excludes 6209 so the bad figure does not pollute the ranges.
Which segment of a designation is the bore, and which fixes the outer diameter, is covered in reading a model number.
How to use
Check these before mounting
- Measure your shaft shoulder fillet — it must be ≤
ra max. - Measure the shoulder diameter — it must be ≥
da min, otherwise the inner ring is under-supported. - Measure the housing shoulder diameter — it must be ≤
Da max. - If it is a 6209: do not use that
Da maxfigure for step 3; ask us instead.
What the table does not contain
- Fit tolerance bands (shaft h5/k5/js5, housing H7/J7 and so on): not in the table, and we do not recommend values here.
- Mounting torque or press-in force: not in the table.
- Heating temperature or induction heater settings: not in the table.
- Clearance selection advice: the table has a clearance group column, but no selection rules.
These depend on your application and equipment and are outside what this table can answer.
Maintenance: only one relevant column
The only maintenance-related column in the parameter table is supplementary lubrication feature, and it reads "not provided" on all 700 rows.
That means the models in this catalogue have no relubrication passage recorded (no oil groove or grease nipple feature). Therefore:
- Do not schedule a relubrication interval as if these were relubricatable bearings;
- Regreasing means disassembly, and the method depends on your application — the table says nothing about it;
- The table also carries no grease brand, fill amount or relubrication interval field, so we publish no numbers for those.
If you need a judgement for real mounting and maintenance conditions, send us the drawing dimensions and the duty (contact us).
A common model with all four mounting dimensions present: 6205. The defective model discussed above: 6209 (treat that Da max cell as unusable until we confirm it).