The principal dimensions are 30x72x19 mm at a weight of 0.35 kg; the further technical details are listed in the specification table. With only one shield this bearing is a directional component: which side faces outwards is a mounting instruction and not a matter of discretion. The single shield turns an otherwise symmetrical bearing into a directional component, and most of what has to be observed with this version follows from that.
On the closed side a sheet-metal part fixed in the outer ring reaches close to a shoulder of the inner ring without touching it; the remaining gap holds back coarse contamination and in doing so generates neither a frictional torque nor a heat source. On the open side the rolling chamber remains accessible: lubricant from the surrounding space can reach the rolling contact, frictional heat can be carried away with it, and relubrication through the assembly is possible in principle — properties that a doubly closed version does not offer.
The mounting direction is thereby part of the design and not left to the assembly floor: the shield faces the loaded surroundings, the open side faces the clean interior supplied with lubricant. Two further points hang on the same asymmetry. First, the grease charge is held back on one side only, so with a vertical shaft, high speed or heavy vibration it has to be checked whether the lubricant remains in the rolling chamber.
Second, the gap is no barrier against liquid or fine dust, so for wet surroundings a contact version or an upstream seal is to be provided. Normal radial clearance is matched to one interference-fitted ring and a moderate temperature difference; because the shield does not touch the rings, it exerts no influence on the clearance itself. Through-hardened standard bearing steel sets the temperature and load frame of the rings.
ManufacturerNTN
Bearing typeDeep-groove ball bearings
Bore d30 mm
Outer Ø D72 mm
Width B19 mm
Weight0.35 kg
Sealsshield on one side
Clearancenormal radial internal clearance
Cagepressed steel cage
Materialstandard bearing steel
Tolerancetolerance class P0/PN (ABEC 1)
Bore typecylindrical bore
€11.36/ pc
incl. VAT, plus shipping · price drops with quantity
In stock
Typically ready to ship in 1–2 days
In stock · ships via DPD, UPS or Deutsche Post
QtyUnit priceDisc.
1 – 4€11.36—
5 – 9€11.02−3 %
10 – 24€10.79−5 %
25 – 49€10.45−8 %
50 – 99€10.23−10 %
4 more for −3% volume discount
From 100 pcs: price and lead time on request – subject to review.
Total (1 pc)€11.36
NTN 6306 ZU1 Kugellager (30x72x19)
— 30 x 72 x 19 mm
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✓Free shipping over €100 · 14-day returns
✓Purchase on invoice – first order paid before dispatch, then 14-day terms for approved business customers
Same dimensions means the same bearing type and matching main dimensions (d × D × B). Sealing, cage, internal clearance and execution (e.g. material, precision, grease fill) are encoded in the suffix and may differ — please check before ordering. Equivalent additionally means the same sealing, internal clearance and tolerance class; the cage and other suffix features (e.g. lubrication groove) may differ.
