16003-NTN bearing: complete specifications & equivalents

Specification table

Source: catalog reference (NTN Ball and Roller Bearings CAT.No.2203-3/E (2024)) · extracted 2026-09-25

Parameters extracted from the official NTN Ball and Roller Bearings catalogue (NTN Ball and Roller Bearings CAT.No.2203-3/E (2024)); NTN® is a trademark of NTN Corporation, used here for identification only — mpnbase is not an authorized NTN distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at ntnglobal.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 16003-NTN model number is decoded

16003 is supplied open, without shields or seals, so the arrangement around it must supply and retain the lubricant. Within the narrow 160xx section of the ISO 15 general plan, multiplying bore code 17 by five gives the 17 mm bore; the 35 mm outside diameter and 8 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 17 mm shaft under normal load, catalogue practice seats it on a j5 shaft fit with an H7 housing bore — confirm against the actual load direction and magnitude before committing. In the NTN catalogue this open execution carries the bare designation; protected variants are ordered separately with suffixes ZZ (shields), LLB/LLF (non-contact seals), LLH (low-torque contact seal) and LLU (contact seal).

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• Mount this 17 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.
• Because the 160xx narrow section shares the 35 mm OD of the 6017 at 17 mm bore but is only 8 mm wide, a housing machined for the wider bearing needs a spacer or relocated circlip — never assume width interchangeability.
• Storage matters for open bearings: 16003-NTN 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.
• Open bearings tolerate the highest speeds in the 16000-series but need a defined regreasing interval; run-to-failure lubrication is the dominant cause of early failure in open 16003 units.
• Shaft and housing fillets must clear the bearing chamfer so the 8 mm-wide ring seats square; provide an undercut or withdrawal groove instead of relying on an oversized radius.
• Measure the shaft, do not trust the drawing: a 17 mm nominal journal worn by even 0.02 mm turns an interference seat into a creeping fit that frets the bore of 16003-NTN.
• The open 16003 has no integral sealing; in the NTN 2203 catalogue the protected variants carry suffixes ZZ (non-contact steel shields), LLB/LLF (non-contact rubber seals), LLU (contact rubber seals) and LLH (a low-torque contact seal with higher speed capability than LLU). A JR or JRX suffix (printed for some thin-section sizes) denotes a pressed-steel cage, not a seal.
• At 17 mm bore the 16003 sits in NTN's small-bore range; ABEC-1/P0 runout is standard, and the pressed-steel cage is adequate up to the grease limiting speed — for higher accuracy (spindles, instruments) ask NTN for a P6 or P5 tolerance-class listing before relying on catalogue P0 figures.
• NTN rates 16003 at 20000 r/min grease limiting speed — this is a high-speed electric-motor range; keep the grease fill at 20–30% of the free bearing volume and avoid mixing grease thickener types if regreasing through the housing.
• NTN rates 16003 at 7.55 kN dynamic (C) and 3.35 kN static (C0), 0.26 kN fatigue load limit Cu; this light-to-medium rating suits fractional-horsepower drives and instruments — for conveying or gearbox duty with shock loads, verify the equivalent dynamic load stays well below C.
• At only 32 g, 16003 is a lightweight bearing that can be handled by hand; still, press it onto the shaft with a sleeve against the inner ring — never through the balls or outer ring.
• The 17×35×8 mm envelope of 16003 gives a D/d ratio of 2.06 and 9.0 mm radial section height — a heavy 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 7.55/3.35 kN load ratings, 0.26 kN fatigue load limit Cu NTN lists the grease limiting speed at 20000 r/min for this designation; oil-mist or jet lubrication raises the ceiling but requires a sealed-housing review. and 32 g mass here are NTN Ball and Roller Bearings CAT.No.2203-3/E figures for 16003 on the 17×35×8 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 16003 in a rated drive.
• NTN's pressed-steel cage (no cage suffix) is the quiet standard for this size; for sustained running close to the limiting speed or for heavy shock duty, ask the NTN channel whether a machined-cage execution of 16003 is listed.
• Order the C3 internal-clearance version (16003 with C3 after the seal code) when the shaft fit is tight or the shaft-to-housing temperature gradient exceeds roughly 10 °C — the residual clearance after mounting, not the catalogue CN figure, decides service life.