21 SeriesInternal gearRotek L6-25N9ZKaydon RK6-25N1Z
21N.0644.19.000 Slewing Ring Bearing
21 Series slewing ring bearing, internal gear, 748 mm OD × 549 mm ID. Interchangeable with Rotek L6-25N9Z, Kaydon RK6-25N1Z.
Specifications
| SlewPro part number | 21N.0644.19.000 |
|---|---|
| Series | 21 Series |
| Bearing design | Four-point contact, single-row ball |
| Gear | Internal gear |
| Raceway diameter | 644 mm (25.35 in) |
| Outside diameter | 748 mm (29.45 in) |
| Inside diameter | 548.6 mm (21.60 in) |
| Overall height | 55.9 mm (2.20 in) |
| Outer ring height | 45.5 mm (1.79 in) |
| Inner ring height | 45.5 mm (1.79 in) |
| Outer ring bore | 645.9 mm (25.43 in) |
| Inner ring outside diameter | 642.1 mm (25.28 in) |
| All diameters on drawing | 29.45 in (748.0 mm), 26.89 in (683.0 mm), 25.43 in (645.9 mm), 25.28 in (642.1 mm), 21.60 in (548.6 mm) |
| All heights on drawing | 2.20 in (55.9 mm), 1.79 in (45.5 mm), 1.32 in (33.5 mm), 0.47 in (11.9 mm) |
| Diametral pitch | 4 |
| Number of teeth | 88 |
| Pitch diameter | 22 in |
| Pressure angle | 20° |
| Approx. weight | 105 lb (48 kg) |
Dimensions from our 3D model; confirm against the certified drawing. Load ratings and life calculations available from our engineers.
Crosses to
| Kaydon | RK6-25N1Z |
|---|---|
| Rotek | L6-25N9Z |
Interchange based on published dimensions; our engineers confirm fit before quoting.
CAD & documents
Get this bearing
Standard lead time 14–16 weeks; expediting available for an additional charge. Pricing quoted within 1–2 business days. Matching pinions available.
Request a QuoteTalk to an engineer
Need help selecting the right part? Our engineers will size it, cross it, and quote it — usually within 1–2 business days.
Not in the catalog? We design to your application, with no engineering charge.


