d - 4 mm

D - 9 mm

B - 4 mm

d₁ - - 5.2 mm

D₂ - - 8.1 mm

r_1,2 - min. - 0.1 mm

d_a - min. - 4.6 mm

d_a - max. - 5.1 mm

D_a - max. - 8.4 mm

r_a - max. - 0.1 mm

Basic dynamic load rating - C - 0.54 kN

Basic static load rating - C₀ - 0.18 kN

Fatigue load limit - P_u - 0.07 kN

Reference speed - 140000 r/min

Limiting speed - 70000 r/min

Calculation factor - k_r - 0.015

Calculation factor - f₀ - 10

Mass bearing - 0.0013 kg

• Model Number: 638/4-2Z
• Inner Diameter：9mm Outer Diameter：4mm Width：4mm
• Type：Deep Groove Ball Bearings
• Update date：2025-12-17
• Application:hanging clamp,universal category,test strip,Dental Drill etc,noise reduction equipment,printing equipment,organic raw materials,food / grain / food equipment,relay,Insect Count,extruder
• Similar models:NSK 638ZZ1 SKF W63806-2RS1 SKF W638/2R-2Z ZEN S63800-2Z ZEN 63801-2RS ISO 63801ZZ SKF W63802R CX 63801-2RS SKF W63804R SKF W638
• BEARING POWER International Trading Co.,Ltd. specialize in 638/4-2Z products，there is large inventory of SKF 638/4-2Z . We has been built up long-term cooperation with SKF company, could make a bulk order of the 638/4-2Z Which SKF 638/4-2Z is the most authentic, must choose BEARING POWER, what a whole variety, reasonable price, guaranteed quality, prompt delivery via Global express.Any inquiry, never hesitate to E-mail or call +86-022-58519721 to contact us.

• Model No.	Inner Diameter	Outer Diameter	Width	Brand	Type
  204190X/204266XC	190,5	266,7	47,62	Gamet	Tapered Roller Bearings
  5207EEG15	35,000	72,000	27,000	SNR	Angular Contact Ball Bearings
  537/532	50,8	107,95	36,512	CRAFT	Tapered Roller Bearings
  6302LLU	15	42	13	NTN	Deep Groove Ball Bearings
  6844-RS	220	270	24	CYSD	Deep Groove Ball Bearings
  BA 167 Z	25,4	31,75	11,13	IKO	Needle Roller Bearings
  BK4520	45	52	20	ISO	Cylindrical Roller Bearings
  EC44238S01	32,59	72,23	19	SNR	Tapered Roller Bearings
  GRAE12-NPPB	12	40	19	NKE	Deep Groove Ball Bearings
  K-L45449/K-L45410	29	50,292	14,224	ZVL	Tapered Roller Bearings
  K34X44X26FV	34	44		Timken	Needle Roller Bearings
  RXLS 6.1/2	165,1	222,25	28,58	SIGMA	Cylindrical Roller Bearings
  NUP412	60	150	35	FAG	CYLINDRICAL ROLLER BEARINGS
  RNAO12x19x10	19		10	FAG	NEEDLE BEARINGS
  241/750	750	1220	475	SKF	SPHERICAL ROLLER BEARINGS
  4814	1.0000	1.0625	1.5000	Hyatt	JOURNAL ROLLER BEARING OUTER RACES
  ULK6012X	.1875	.3750	.1250	RMB	DEEP GROOVE BALL BEARINGS
  NKI-50/35	50	68	35	CONSOLIDATED	NEEDLE BEARINGS
  95x110x10mm	95	110	10	CONSOLIDATED	OIL SEALS
  62805	25	37	8	CONSOLIDATED	DEEP GROOVE BALL BEARINGS