6348 bearing: complete specifications & equivalents
The 6348 is a ISO 15 radial bearing sized 240 x 500 x 95 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NSK |
| Bore diameter d | 240 mm |
| Outer diameter D | 500 mm |
| Width B | 95 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 515 kN |
| Basic static load rating C0 | 625 kN |
| Mass | 94400 g |
| Manufacturer designation | NSK 6348 |
| Standard | ISO 15 |
| Catalog version | NSK Rolling Bearings E1103 Part C |
| Last verified | 2026-09-24 |
Source: catalog reference (NSK Rolling Bearings E1103 Part C) · extracted 2026-09-24
Dimensions in inches & 6300-series range
| Bore d | 9.449 in |
|---|---|
| Outer diameter D | 19.685 in |
| Width B | 3.74 in |
| ISO bore code | 48 |
| Radial section height (D−d)/2 | 130 mm |
| Smallest bore in 6300-series | 10 mm |
| Largest outer diameter in 6300-series | 500 mm |
| Width range across 6300-series | 11–95 mm |
| Bore position in 6300-series (smallest first) | 34 of 34 |
| Bore above smallest 6300-series size | 230 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 6348 | ISO-INTERCHANGE | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension interchange; ratings above are NSK E1103 values and differ by brand — verify per supplier. |
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 6348 model number is decoded
In the 6300-series (ISO 15 diameter series 3) the last two digits encode the bore: 6348 carries bore code 48 = 240 mm. Outside diameter 500 mm and width 95 mm come from the ISO 15 boundary-dimensions general plan. With no seal suffix the bearing is open: no shields or seals are fitted and lubrication is supplied by the application. For normal-load mounting with a rotating inner ring on a 240 mm shaft, typical catalogue practice is a m6 shaft seat with an H7 housing bore — verify against the actual load direction and magnitude.
Typical equipment & failure modes
Common applications
- heavy conveyors
- pulp and paper machinery
- medium and heavy industrial drives
- large gearboxes
Known failure patterns
- contamination wear from dust and dirt ingress through the open arrangement
- lubricant starvation when no regreasing interval is maintained
- false brinelling from vibration while the shaft is stationary
- fretting corrosion on a loose shaft seat
Selection pitfalls — read before you substitute
- Mount this 240 mm bore bearing by heating the inner ring (induction heater, max 120 °C) — never drive it home through the outer ring or balls, that brinells the raceways.
- The 63xx medium series gains rating at 240 mm bore through a 500 mm OD and 95 mm width; the heavier rolling elements also trade away some speed versus a 6248.
- The open 6348 has no lubricant retention: grease escapes and contaminants migrate straight into the 240×500×95 mm raceway, so specify a sealed arrangement for dusty or washdown duty.
- Open bearings tolerate the highest speeds in the 6300-series but need a defined regreasing interval; run-to-failure lubrication is the dominant cause of early failure in open 6348 units.
- Deep-groove ball bearings tolerate only minutes of misalignment; if the 500 mm housing cannot be aligned, switch to a self-aligning type rather than shimming 6348.
- The open 6348 needs external sealing and application-supplied lubrication; in the NSK catalogue the protected variants are separate order numbers with suffixes ZZ (shields), VV (non-contact rubber seals) and DDU (contact rubber seals).
- The 515/625 kN ratings, mass 94400 g here are NSK Rolling Bearings E1103 Part C catalogue figures for 6348; this seal/size combination has no counterpart in the SKF 17000 extract used elsewhere on this site, so the page rests on a single manufacturer source — internal geometry and ratings legitimately differ between brands, so re-verify before substituting in a rated drive.
Frequently asked questions
What are the dimensions of a 6348 bearing?
A 6348 deep-groove ball bearing has a 240 mm bore, 500 mm outer diameter and 95 mm width (9.449 × 19.685 × 3.74 in), per ISO 15 boundary dimensions. It is an open bearing with no seals or shields.
How does the 6348 bore code work?
The last two digits of 6348 are bore code 48, giving 48 × 5 = 240 mm bore. The 500 mm outside diameter and 95 mm width follow the ISO 15 diameter series, not the bore code alone.
What does no suffix on 6348 mean?
A bare 6348 designation means open: no shields or seals, normal CN radial clearance and P0 normal tolerance unless further suffixes are ordered. The application must supply and retain the lubrication.
How does the 6300 compare with other series at the same 240 mm bore?
The '3' is the medium diameter series: 500×95 mm, 130.0 mm radial section at 240 mm bore, carrying more load than a 6248 but needing a larger housing bore and giving up some speed.
What is the NSK designation and catalogue data for 6348?
In the NSK Rolling Bearings catalogue (E1103 Part C) this size is listed as 6348 — the open (unsealed) execution, 240×500×95 mm per ISO 15. Quoted values: C 515 kN, C0 625 kN, mass 94400 g. The industry-neutral page spelling 6348 follows the seal-suffix convention used across this site, not NSK order-number spelling. Reference and limiting speeds are not tabulated in the E1103 dimension tables used here; consult NSK speed tables before high-speed service.
Reviewed & verified by the MPN Base engineering desk against source catalog NSK Rolling Bearings E1103 Part C on 2026-09-24. Read our editorial & correction policy.