61910-NSK bearing: complete specifications & equivalents

Specification table

Source: catalog reference (NSK Rolling Bearings E1103 Part C) · extracted 2026-09-24

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 61910-NSK model number is decoded

In the 61900-series (diameter series 9 of ISO 15) the last two digits encode the bore: 61910 carries bore code 10 = 50 mm. Outside diameter 72 mm and width 12 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 50 mm shaft, typical catalogue practice is a k5 shaft seat with an H7 housing bore — verify against the actual load direction and magnitude. In the NSK catalogue this open execution carries the bare designation; protected variants are ordered separately with suffixes ZZ (steel shields), VV (non-contact rubber seals) and DDU (contact rubber seals).

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• Temperature rise and interference fits consume internal clearance on this 50 mm bore: a CN bearing on a tight, hot shaft can lose all residual clearance — size 61910 with C3 for those conditions.
• The 619xx thin section at 50 mm bore (11.0 mm section height) cannot shrug off the misalignment a standard section tolerates; keep the housing bores round and aligned, or edge contact will spall the raceways early.
• The open 61910-NSK has no lubricant retention: grease escapes and contaminants migrate straight into the 50×72×12 mm raceway, so specify a sealed arrangement for dusty or washdown duty.
• Storage matters for open bearings: 61910-NSK leaves the factory with rust preventive only, so clean it and apply the service grease at assembly even if the rings look oily from the wrapper.
• Measure the shaft, do not trust the drawing: a 50 mm nominal journal worn by even 0.02 mm turns an interference seat into a creeping fit that frets the bore of 61910-NSK.
• The housing bore for the 72 mm OD should be round within IT7; an oval bore pinches the outer ring of 61910-NSK and shows up later as two-point loaded raceway wear.
• The open 61910 has no integral sealing; in the NSK E1103 catalogue the protected variants carry suffixes ZZ (non-contact steel shields), VV (non-contact rubber seals) and DDU (contact rubber seals). NSK does not offer a low-torque contact seal equivalent to NTN's LLH in this catalogue — for high-speed sealed duty specify the VV non-contact seal and an external housing labyrinth.
• The 50 mm bore puts 61910 in NSK's general-purpose industrial range; the standard pressed-steel cage and CN clearance cover most electric-motor and pump duty. NSK's VV non-contact seal is the high-speed choice here — DDU contact seal costs roughly 30–40% of the open-bearing speed ceiling.
• At 16 kN dynamic load rating (C) and 11.7 kN static (C0), 61910 is a medium-load NSK bearing suitable for most electric-motor and pump duty; the C0/C0r ratio matters for preloaded or thrust-loaded arrangements, so confirm the static safety factor with the NSK catalogue.
• At 135 g, 61910 is light enough for hand assembly but should be pressed on with a fitting sleeve against the inner ring; do not strike the outer ring or cage with a hammer.
• The 50×72×12 mm envelope of 61910 gives a D/d ratio of 1.44 and 11.0 mm radial section height — this NSK thin section saves space but is sensitive to misalignment and shock; confirm the housing stays round within IT7 and the shaft does not deflect past the raceway contact angle under load.
• The 16/11.7 kN load ratings, mass 135 g here are NSK Rolling Bearings E1103 Part C catalogue figures for 6910 on the 50×72×12 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 61910 in a rated drive. NSK does not tabulate reference or limiting speeds in the E1103 Part C dimension tables used for this page — consult NSK's separate speed-rating tables before high-speed service.
• NSK does not recommend washing new shielded or sealed bearings; the rust-preventive film on open units is compatible with standard lithium greases and needs no removal unless the application demands a special fill.
• NSK's VV non-contact seal keeps frictional torque close to the open 61910; in motor duty where heat build-up matters, VV is the usual compromise between debris protection and speed capability.