3310-DNRCBM bearing: complete specifications & equivalents
The 3310-DNRCBM is a ISO 15 radial bearing sized 50 x 110 x 44.4 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 50 mm |
| Outer diameter D | 110 mm |
| Width B | 44.4 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 81.9 kN |
| Basic static load rating C0 | 69.5 kN |
| Fatigue load limit Pu | 3 kN |
| Reference speed (thermal) | 6700 rpm |
| Limiting speed (mechanical) | 5600 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 1950 g |
| Manufacturer designation | 3310 DNRCBM |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018) |
| Last verified | 2026-09-27 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018)) · extracted 2026-09-27
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018)); SKF® and SKF Explorer® are trademarks of AB SKF, used here for identification only — mpnbase is not an authorized SKF distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at skf.com.
Dimensions in inches & 3300-series range
| Bore d | 1.969 in |
|---|---|
| Outer diameter D | 4.331 in |
| Width B | 1.748 in |
| ISO bore code | 10 |
| Radial section height (D−d)/2 | 30 mm |
| Smallest bore in 3300-series | 15 mm |
| Largest outer diameter in 3300-series | 240 mm |
| Width range across 3300-series | 19–92.1 mm |
| Bore position in 3300-series (smallest first) | 9 of 20 |
| Bore above smallest 3300-series size | 35 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 3310-A | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 50×110×44.4 mm envelope with catalogue ratings within 10 %; 3310 A is the stamped steel cage, open arrangement execution of this size — boundary dimensions interchangeable, execution differs. |
| 3310-ATN9 | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 50×110×44.4 mm envelope with catalogue ratings within 10 %; 3310 ATN9 is the glass-fibre PA66 cage, open arrangement execution of this size — boundary dimensions interchangeable, execution differs. |
| 3310-DMA | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 50×110×44.4 mm envelope, but catalogue C/C0 differ between executions (81.9/69.5 kN vs 93.6/85 kN) — boundary dimensions match, not a load-rating equivalent. |
| 3310-A-2Z | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 50×110×44.4 mm envelope with catalogue ratings within 10 %; 3310 A-2Z is the stamped steel cage, shields (-2Z) execution of this size — boundary dimensions interchangeable, execution differs. |
| 3310-A-2RS1 | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 50×110×44.4 mm envelope with catalogue ratings within 10 %; 3310 A-2RS1 is the stamped steel cage, contact NBR seals (-2RS1) execution of this size — boundary dimensions interchangeable, execution differs. |
Interchange levels: full standard interchange · partial verify parameters · verify manual confirmation required. Links resolve to the equivalent model's specification page where available.
How the 3310-DNRCBM model number is decoded
3310 DNRCBM is SKF's 50 mm-bore double-row angular-contact ball bearing of the 3300 series — two ball rows back-to-back for two-direction axial location in one unit, 50×110×44.4 mm. A on a double-row bearing means no filling slots, so both rows carry their full ball complement in both directions. D marks a two-piece (split) inner ring that simplifies mounting of the heavy 33-series section. NR adds a snap-ring groove in the outer ring supplied with the appropriate snap ring, and CB gives controlled axial clearance. DNRCBM combines the split inner ring, snap ring (NR), controlled CB clearance and a machined brass ball-centred M cage. CB means universally matchable with Normal axial internal clearance: the two side faces are ground so any two units form DB (back-to-back), DF (face-to-face) or DT (tandem) sets without regrinding. Envelope 50×110×44.4 mm (1.969×4.331×1.748 in), 30.0 mm radial section height, C 81.9 kN, C0 69.5 kN, Pu 3 kN.reference speed 6,700 r/min (thermal) and limiting speed 5,600 r/min (mechanical), catalogue mass 1950 g. Selection figures for 3310 DNRCBM: the static-to-dynamic ratio C0/C is 0.85, Pu 3 kN is about 4 % of C, and catalogue mass works out to roughly 39 g per millimetre of bore. Envelope economics: the 44.4 mm width over a 30.0 mm section yields 1.48 mm of ring width per section millimetre, and the bearing weighs 1950 g for 81.9 kN of dynamic capacity — about 24 g per rated kN. Speed-ratio note for this exact unit: the reference speed is 6,700 r/min against a 5,600 r/min limiting speed, i.e. a reference-to-limit ratio of 1.20.
Typical equipment & failure modes
Common applications
- two-direction thrust positions without room for a paired single-row set
- centrifugal pump shafts
- elevator and hoist machinery
Known failure patterns
- tilted mounting that loads one double row more heavily than the other
- false brinelling on the loaded row while the shaft stands idle under vibration
- snap-ring groove distress or ring rotation if the NR snap ring is not seated fully in its groove
- brinelling from pressing the ring home through the balls or from static overload
- hard-particle indentation of the asymmetric raceway in unfiltered oil
Selection pitfalls — read before you substitute
- The D executions have a two-piece inner ring: mount both halves square to each other, never press on the outer ring, and keep the split faces clean during fitting.
- Controlled axial clearance is the heart of the design: CB denotes controlled Normal axial clearance between the two rows; check residual clearance after mounting and at operating temperature.
- Interference goes on the rotating ring (about k5 at 50 mm bore); the wide 44.4 mm ring is sensitive to tilted seats, so check squareness before clamping.
- The D executions have a two-piece inner ring: mount both halves square to each other, never press on the outer ring, and keep the split faces clean during fitting.
- The D executions have a two-piece inner ring: mount both halves square to each other, never press on the outer ring, and keep the split faces clean during fitting.
- Catalogue ratings are SKF PUB BU/P1 17000 figures for 3310 DNRCBM as the double d nr cb m execution; the other order numbers of the 3310 size are different products and may carry different ratings — always quote the full designation when purchasing.
Frequently asked questions
What are the dimensions and catalogue data of 3310-DNRCBM?
3310 DNRCBM measures 50 mm bore × 110 mm OD × 44.4 mm width (1.969 × 4.331 × 1.748 in), mass about 1950 g. SKF 17000 ratings: C 81.9 kN, C0 69.5 kN, Pu 3 kN, reference speed 6,700 r/min (thermal) and limiting speed 5,600 r/min (mechanical).
What does the DNRCBM suffix mean?
A on a double-row bearing means no filling slots, so both rows carry their full ball complement in both directions. D marks a two-piece (split) inner ring that simplifies mounting of the heavy 33-series section. NR adds a snap-ring groove in the outer ring supplied with the appropriate snap ring, and CB gives controlled axial clearance. DNRCBM combines the split inner ring, snap ring (NR), controlled CB clearance and a machined brass ball-centred M cage. CB means universally matchable with Normal axial internal clearance: the two side faces are ground so any two units form DB (back-to-back), DF (face-to-face) or DT (tandem) sets without regrinding.
What does the D mean in DNRCBM?
D marks a two-piece inner ring, used on the heavy 33-series executions to simplify mounting; the rest of the suffix identifies the cage (MA brass outer-ring-centred, M brass ball-centred, J1 stamped steel, TN9 PA66) and snap-ring/clearance options (NR, CB).
Does the 3310 double-row bearing need pairing?
No — both ball rows are built into one bearing, so bidirectional location does not require a second unit. Controlled axial clearance is part of the design rather than a field adjustment.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018) on 2026-09-27. Read our editorial & correction policy.