LM300849-811 bearing: complete specifications & equivalents

Specification table

Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB) · extracted 2026-09-28

Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB); 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.

Cross references & equivalents

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 LM300849-811 model number is decoded

Speed envelope and thermal behaviour: at 8,000 r/min thermal reference, the 41 mm bore shaft runs at a dn of 328k, and the 13.5 mm section dissipates heat through the cup-to-housing contact path; the 9,500 r/min mechanical ceiling reflects cage strength, and the 240 g spinning cone contributes gyroscopic moment under rapid speed reversal. From a specification standpoint the 811 cup is the controlling half of LM300849 for housing design — it sets the 68 mm OD and the outer abutment diameter — while the LM 300849 cone controls shaft fit at the 41 mm bore; the 17.5 mm width is the result of the two together.The SKF LM 300849/811 is a 41×68×17.5 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.Numbering ties the bearing to its inch-series envelope: LM300849 means a cone and cup matched pair in the LM300800-series series — which is why the 41×68×17.5 mm outline swaps dimensionally with other inch-series bearings of the same code. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. The 6.3 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.09 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Specify pairs rather than single units wherever thrust reverses: the tapered contact of LM300849 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• On this 41 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight LM300849 pair heats, loses setting control and smears the roller-rib contact.
• The LM300800-series inch series at 41 mm bore (68×17.5 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.
• Do not mix brands or executions inside one LM300849 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.
• O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common LM300849 mounting error.
• Shaft and housing fillets must clear the bearing chamfer so the 17.5 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.
• The 53.6/58.5 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.
• SKF lists several executions of LM300849 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 300849/811 designation when purchasing and match the execution to the mounting arrangement.