6321NSKBall

Name: NSK 6321 Ball Bearing
Brand: NSK
SKU: 6321

6321 is a NSK ball bearing, bore 105 mm, O.D. 225 mm, width 49 mm, dynamic rating 41,300 lbs. Dimensions, drawing, interchanges and price.

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Bore d105mm

Outside dia. D225mm

Width B49mm

Dynamic Cr41,300lbs

Static C0r34,500lbs

Limiting speed2,600rpm

Weight8.119kg

Cr / C0r1.2

Mean dia. dm165mm

Original catalogue drawing - NSK catalogue, page 19

Scanned from the manufacturer catalogue page listing this part number. All part numbers printed on that table share the same drawing.

Scale cross-section

Blue = inner / outer ring, yellow = rolling element. Drawn to scale from this part's own dimensions for selection reference only - not a manufacturing or assembly drawing.

Dimension table (mm / inch)

Symbol	Dimension	mm	inch
d	Bore diameter	105	4.1339
D	Outside diameter	225	8.8583
B	Inner-ring / bearing width	49	1.9291
r	Chamfer (min)	2.489	0.098

Notes

Weights are given in kg. Load ratings are shown in both the original catalogue units and the converted value (1 N = 0.2248 lbf). Data is provided for selection reference only - confirm against the latest official catalogue before ordering.

Main dimensions

Bore d (mm)	105
Bore d (in)	4.1339
Outside dia. D (mm)	225
Outside dia. D (in)	8.8583
Width B (mm)	49
Width B (in)	1.9291

Load ratings & speeds

Basic dynamic load rating Cr (lbs)	41300
Basic static load rating Cor (lbs)	34500
Limiting speed - grease (rpm)	2,600
Limiting speed - oil (rpm)	3,200
Factor f0	13.2

Weight

Weight (kg)	8.119

Mounting dimensions (fillets / shoulders)

Chamfer r (in)	0.098
Shaft shoulder da min (in)	4.685
Shaft shoulder da max (in)	5.437
Housing shoulder Da max (in)	8.307

Bearing life (ISO 281 basic rating life)

C / P	Equivalent load P (N)	L₁₀ (10⁶ rev)	L_10h at 800 rpm
4	45,928	64	1,333
6	30,619	216	4,500
8	22,964	512	10,667
10	18,371	1,000	20,833
15	12,247	3,375	70,312

Basic rating life per ISO 281: L₁₀ = (C/P)³ with C = 183,712 N. Hours = L₁₀ x 10⁶ / (60n). Life-modification factors for lubrication, contamination and temperature (a_ISO) are not included.

Source & traceability

Brand	NSK
Source catalogue	NSK inch product catalogue
Catalogue page	p.21 (dimensions) / p.22 (ratings)

Dimensions in inches and millimetres, load ratings in lbs.

Interchange - same dimensions, other brands

Designation	Brand	Type	d	D	B/T	Dyn. rating	kg
1321-M	FAG	Ball	105	225	49	158 kN	10.3
6321	FAG	Ball	105	225	49	188 kN	8.7
30321-XL	FAG	Tapered Roller	105	225	49	530 kN	10.5
7321-B-MP	FAG	Precision / Angular Contact	105	225	49	209 kN	9
7321-B-XL-MP	FAG	Precision / Angular Contact	105	225	49	225 kN	9.3

Same dimensions, same brand

Designation	Brand	Type	d	D	B/T	Dyn. rating	kg
1321	NSK	Ball	105	225	49	169 kN	9.58
7321B	NSK	Ball	105	225	49	42,800 lbs	9.389
321	NSK	Cylindrical Roller	105	225	49	71,500 lbs	8.618
NU321E	NSK	Cylindrical Roller	105	225	49	525 kN	9.84
HR30321	NSK	Tapered Roller	105	225	49	560 kN	9.52
HR30321J	NSK	Tapered Roller	105	225	49	102,000 lbs	9.525
HR31321J	NSK	Tapered Roller	105	225	49	76,400 lbs	10.043
7321	NSK	Precision / Angular Contact	105	225	49	210 kN	9.43

Nearby bore sizes

Designation	Brand	Type	d	D	B/T	Dyn. rating	kg
1221	NSK	Ball	105	190	36	82.5 kN	4.43
1321	NSK	Ball	105	225	49	169 kN	9.58
16021	NSK	Ball	105	160	18	57 kN	1.24
2221	NSK	Ball	105	190	50	120 kN	5.73
6021	NSK	Ball	105	160	26	16,300 lbs	1.592
6221	NSK	Ball	105	190	36	29,900 lbs	3.697
6821	NSK	Ball	105	130	13	4,440 lbs	0.313
6921	NSK	Ball	105	145	20	9,460 lbs	0.835

Request a quotation for 6321

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Online enquiry form richard@bearingsfit.com WhatsApp +86 156 2149 6516