d - 4 mm

D - 8 mm

B - 3 mm

C - 3 mm

d1 - 5 mm

d2 - – mm

r1 min. - 4,8 mm

r2 min. - 4,8 mm

D1 - 7,4 mm

D2 - 0,1 mm

da min. - 4,9 mm

Da max. - 7,5 mm

ra max. - 0,1 mm

Weight - 0,0005 Kg

Basic dynamic load rating (C) - 0,225 kN

Basic static load rating (C0) - 0,072 kN

Fatigue load limit (Pu) - 0,003

Reference speed - 150000 r/min

Limiting speed - 75000 r/min

Calculation factor (f0) - 7,2

Calculation factor (kr) - 0,02

• Model Number:W637/4X-2Z
• Inner Diameter：4mm Outer Diameter：8mm Width：3mm
• Type：Deep Groove Ball Bearings
• Update date：2025-12-11
• Application:rolling machine,equipment,joint protection,welding equipment,security equipment,X-ray Equipment,Oral Image,Plastic Equipment,Vertical machining,safety testing,electronic materials
• Similar models:ISO 637 ISO 637-2RS ISB SS637/3 ISO 637ZZ NSK 637ZZ1 FBJ 637 KOYO 637ZZ SKF W637/9-2ZS SKF W637/9-2Z SKF W637/8XR
• BEARING POWER International Trading Co.,Ltd. specialize in W637/4X-2Z products，there is large inventory of SKF W637/4X-2Z . We has been built up long-term cooperation with SKF company, could make a bulk order of the W637/4X-2Z Which SKF W637/4X-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.

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  N232	160	290	48	FAG	CYLINDRICAL ROLLER BEARINGS
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  220548	1.3750	2.0000	3.0000	BAL	JOURNAL ROLLER ASSEMBLIES
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