6400 Series Deep Groove Ball Bearings

The heavy series, and the largest envelope at any bore it covers: at the same bore a 6400 is bigger across and wider than anything else here — a 6404 is 72 mm across on a 20 mm bore, against 47 mm for the 6204. It starts at 6403; there is no 6400, 6401 or 6402. It also stops at a 100 mm bore, which the 6000, 6200 and 6300 do not, so the biggest single bearing here is a 6360 at 620 mm across rather than a 6420.

The step from medium to heavy is the biggest single step on the ladder. On a 20 mm shaft the outside diameter runs 32 (61804), 37 (61904), 42 (6004 and 16004), 47 (6204), 52 (6304) and 72 mm (6404): light to medium adds 5 mm, and medium to heavy adds 20 mm on its own. That is what "heavy" means in a designation — not a heavier bearing of the same size, but a substantially larger housing built around the same shaft.

It is also the only deep groove series here that does not start at a 10 mm bore. The 6400 series begins at 6403, a 17 mm bore — there is no 6400, 6401 or 6402 — and runs to 6420 at a 100 mm bore, 250 mm outside diameter and 58 mm wide. That is 18 bore codes, and the widest envelope at any bore it covers: no other series, of any type here, is larger across or wider at the same bore. What it is not is the widest series overall, and the reason is the same one that gives this page its shape — this series stops at a 100 mm bore. Which series go further, and by how much, is in the note above the size table. The top four sizes carry a 4 mm minimum chamfer, the largest in this series.

What all that size buys is load capacity and shaft stiffness, and the price is the housing — which at this end of the ladder is no longer a rounding error. So the heavy series is the right answer where the shaft diameter is fixed, the load is genuinely heavy, and the housing can be built around the bearing. It is the wrong answer in a tight design that has already run out of room: past a point, changing bearing type serves better than going up another diameter series. That is general engineering practice rather than anything ISO 15 decides — the standard fixes the dimensions, not the choice.

Every designation in the table below links to its own page with the ISO 15 dimensions, the bore-code arithmetic, the ISO 5753-1 clearance ranges for its bore, and the same-bore comparison against every other series.

This series runs from a 17 mm to a 100 mm bore. The sub-library as a whole reaches 300 mm of bore, and the widest single bearing in it is a 6360, 620 mm across, in the 6300 series. This one stops short of it.

d = bore diameter, D = outside diameter, B = width. All of them are ISO 15 standard values and are the same for every manufacturer. r s min is the minimum single chamfer dimension the plan gives; its matching maximum is in ISO 582, which is why the column says “min” and not an equality. The last column is derived: radial section = (D − d) / 2, the wall thickness you are working with when you size the housing. No load rating and no limiting speed appears here — see the bearings index for why.

Outside diameter × overall size in millimetres, for the 5 smallest bores in this database. The full charts, one per type, are on the bearings index. Reading a row is what a machine designer does when the shaft is already fixed: the bore does not change, the housing bore does. Across the type boundary the last number changes meaning — it is a width above and a height below — so compare within a type, then decide whether the job wants a ball bearing, a tapered roller or a thrust bearing at all. The 6 series whose type has no bore are not rows here: they are indexed by the shaft they run on, and their chart is above.