Tapered Roller Bearings
Tapered roller bearing 30321
Tapered roller bearing 30321, single-row, metric series, boundary dimensions 105 mm × 225 mm × 49 mm. Specifications below are model-bound catalog values; send your application details through the RFQ for a confirmed quotation.
Last updated: 2026-10
Specifications
| Specification | Value |
|---|---|
| Bore diameter (d) | 105 mm |
| Outside diameter (D) | 225 mm |
| Width (B) | 49 mm |
| Outer ring width (C) | 41 mm |
| Overall width (T) | 53.5 mm |
| Minimum chamfer (r min.) | 4 mm |
| Minimum chamfer (r1 min.) | 3 mm |
| Basic dynamic load rating (Cr) | 464 kN |
| Basic static load rating (C0r) | 432 kN |
| Fatigue load limit (Cu) | 56 kN |
| Limiting speed, grease lubrication | 1700 min-1 Catalog limiting speed — verify suitability for your application before use. |
| Limiting speed, oil lubrication | 2300 min-1 Catalog limiting speed — verify suitability for your application before use. |
| Load center distance (a) | 43.1 mm |
| Constant e | 0.35 dimensionless |
| Axial load factor (Y1) | 1.73 dimensionless |
| Axial load factor (Y0) | 0.95 dimensionless |
| Shaft abutment diameter (da min.) | 123 mm |
| Shaft abutment diameter (db max.) | 132 mm |
| Housing abutment diameter (Da max.) | 211 mm |
| Fillet radius (r max.) | 3 mm |
| Inner-ring fillet radius (rb max.) | 2.5 mm |
| Reference mass | 8.74 kg |
All values above are model-bound catalog values traceable to a collected source. Fields without collected evidence are not published; ask with your inquiry and we confirm them at quotation.
Applications and selection notes
Tapered roller bearings carry combined radial and axial load, with the axial capacity sharing the same geometry as the radial capacity through the tapered raceways. They are supplied as a separable cup and cone, mounted opposed in single, double or multiple arrangements. Typical service: wheel hubs, gear reducers, mining and construction equipment, machine-tool spindles and steering systems.
The 3xxxx series on this page is the standard single-row inch/metric series; the contact angle grows through the series from light to heavy axial capacity. Because the two rings are separable, mounting sets the internal clearance mechanically — the application must specify the end-play or preload the assembly needs.
How to read the specification table
Unlike ball bearings, a tapered position is selected as an arrangement: two opposed single-row bearings, or a double-row execution, with the clearance set at assembly. The table’s ratings are catalog values for the single bearing; the arrangement’s capacity and stiffness follow from the mounting geometry. State the application’s axial demands and the target clearance in the RFQ so the offer matches the arrangement.
Further reading
30321 — buying questions
What does the designation 30321 mean?
30321 is a standard boundary-dimension designation: the dimension series fixes the outside diameter and width proportions, and the bore code fixes the bore diameter — 105 mm for this bearing. Two bearings carrying the same designation from conforming manufacturers are dimensionally interchangeable; execution (seals, clearance class, cage) is the part that can differ, so state the execution you need when you request a quotation.
Are the catalog load rating and speed of 30321 enough for my application?
The table lists Cr = 464 kN and a catalog limiting speed of 1700 min-1. The load rating is the starting point of a life calculation, and the limiting speed is a catalog value for the manufacturer’s execution — seals, fits, temperature and lubrication all reduce the usable speed in a real assembly. Send the application conditions with your inquiry and we confirm suitability before quoting; do not size from the catalog speed alone.
What information do you need to quote 30321?
Four things, in one message: the designation (and execution — seals, clearance class, precision class, if not standard), the quantity, the destination country, and any documents you require. Application conditions such as speed, load direction and temperature are welcome and let us verify the execution instead of assuming it. Quotation, lead time and the exact document set come back in writing.
Ordering & documentation
Documents
Standard export documentation — commercial invoice, packing list and certificate of origin — accompanies every shipment. The exact document set for your order, and any material or inspection paperwork you require alongside it, is confirmed in writing at quotation before the order is placed.
Quotation
To quote 30321, send: the designation and required execution, quantity, destination country, and any required documents. Adding the application conditions (speed, load direction, temperature, fit) lets us confirm the execution and clearance class instead of quoting blind.
Sample & supply
Sample quantities of standard-designation bearings such as 30321 are available for evaluation before a bulk order. Bulk supply runs through own production plus a qualified outsourcing network, so catalog items are not capped by own-factory capacity; the confirmed lead time is stated in the quotation.
Current confirmed lead-time practice: 15-30 business days for bulk standard bearings; 5-10 for samples. Standard quality system: ISO 9001.
Storage & shipping
Bearings are packed moisture-protected for export and should be stored flat, in unopened original packaging, in a dry indoor area away from temperature swings. Do not unwrap or rotate bearings before mounting; rotate only by the ring being pressed, never through the rolling elements.