6313-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 6313-NTN model number is decoded

6313 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 13 by five gives the 65 mm bore; the 140 mm outside diameter and 33 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 65 mm shaft under normal load, catalogue practice seats it on a k5 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

• Interference on a 65 mm shaft plus running heat consumes radial clearance: where the shaft runs hot or the fit is tight, order 6313 with C3 clearance and re-check the residual value after mounting.
• The 63xx medium series gains rating at 65 mm bore through a 140 mm OD and 33 mm width; the heavier rolling elements also trade away some speed versus a 6213.
• The open 6313-NTN has no lubricant retention: grease escapes and contaminants migrate straight into the 65×140×33 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 6313 units.
• Grease compatibility is not guaranteed between fills: mixing lithium and polyurea thickeners in a 6300-series position can soften the mixture and leak — clean out the old fill before switching grease types.
• Measure the shaft, do not trust the drawing: a 65 mm nominal journal worn by even 0.02 mm turns an interference seat into a creeping fit that frets the bore of 6313-NTN.
• The open 6313 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 65 mm bore 6313 is in NTN's upper general-purpose range; the pressed-steel cage is standard but mid-section 63xx sizes at this bore can be ordered with a machined brass cage (suffix M) for heavy-shock or very-low-speed duty — confirm cage material with the NTN channel if the application sees impact loads.
• NTN lists the grease limiting speed at 4900 r/min for 6313; this is a large or heavy-section size where centrifugal force and cage inertia cap the speed — for higher shaft speeds either step to a smaller bearing on the same bore or consult NTN for an oil-lubricated, machined-cage variant.
• At 103 kN dynamic load rating (C) and 60 kN static (C0), 4.6 kN fatigue load limit Cu, 6313 is a heavy-load bearing for industrial gearboxes and large conveyors; NTN expects a machined brass cage (suffix M) at this rating for shock duty, and the static C0 must be checked against any mounting or lifting loads.
• At 2080 g (2.1 kg), 6313 needs mechanical handling for mounting; NTN recommends induction heating the inner ring (max 120 °C) rather than pressing cold, and a lifting eye if the housing is pre-assembled.
• The 65×140×33 mm envelope of 6313 gives a D/d ratio of 2.15 and 37.5 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 103/60 kN load ratings, 4.6 kN fatigue load limit Cu NTN lists the grease limiting speed at 4900 r/min for this designation; oil-mist or jet lubrication raises the ceiling but requires a sealed-housing review. and 2080 g mass here are NTN Ball and Roller Bearings CAT.No.2203-3/E figures for 6313 on the 65×140×33 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 6313 in a rated drive.
• NTN date-codes its packaging; rotate stock first-in-first-out, because the grease inside sealed units ages on the shelf — after three to five years of storage, check the grease condition before putting the bearing into service.
• Two NTN bearings of the same designation from different production lots can carry minor internal-geometry revisions; for paired or preloaded arrangements on one shaft, order a single lot through the NTN distributor.