6334-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 6334-NSK model number is decoded

6334 is supplied open, without shields or seals, so the arrangement around it must supply and retain the lubricant. Within the medium 63xx section (diameter series 3 of ISO 15), multiplying bore code 34 by five gives the 170 mm bore; the 360 mm outside diameter and 72 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 170 mm shaft under normal load, catalogue practice seats it on a m6 shaft fit with an H7 housing bore — confirm against the actual load direction and magnitude before committing. 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

• Mount this 170 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 170 mm bore through a 360 mm OD and 72 mm width; the heavier rolling elements also trade away some speed versus a 6234.
• The open 6334-NSK has no lubricant retention: grease escapes and contaminants migrate straight into the 170×360×72 mm raceway, so specify a sealed arrangement for dusty or washdown duty.
• Storage matters for open bearings: 6334-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.
• The housing bore for the 360 mm OD should be round within IT7; an oval bore pinches the outer ring of 6334-NSK and shows up later as two-point loaded raceway wear.
• Suffixes stack in a defined order — clearance follows the seal code, e.g. 6334-NSK-C3. No clearance suffix means normal CN clearance.
• The open 6334 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 170 mm bore places 6334 in NSK's large-size range; at these diameters the pressed-steel cage is speed-limited and NSK commonly supplies a machined brass cage (suffix M) as an option. Verify cage material and relubrication interval with the NSK distributor, and do not extrapolate small-bore speed ratings to this size.
• NSK rates 6334 at 360 kN dynamic (C) and 355 kN static (C0); this is an extreme-load bearing at the top of the E1103 Part C single-row deep-groove range, where mounting, shaft stiffness and housing alignment dominate the achievable life. Consult NSK engineering for a full application review rather than relying on catalogue L10 alone.
• At 36600 g (36.6 kg), 6334 is a very heavy NSK bearing where handling and mounting method directly affect service life; NSK requires induction heating of the inner ring (max 120 °C), a mechanical puller for removal, and a defined lifting procedure to avoid damaging the cage.
• The 170×360×72 mm envelope of 6334 gives a D/d ratio of 2.12 and 95.0 mm radial section height — a heavy NSK section built for high-load, lower-speed duty; specifying it in a high-rpm motor generates excess heat and shortens grease life, so prefer a 62/63-series there.
• The 360/355 kN load ratings, mass 36600 g here are NSK Rolling Bearings E1103 Part C catalogue figures for 6334 on the 170×360×72 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 6334 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's VV non-contact seal keeps frictional torque close to the open 6334; in motor duty where heat build-up matters, VV is the usual compromise between debris protection and speed capability.
• 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.