The 6904ZZ bearing is a common deep groove ball bearing, featuring a double-sided metal dust cover (ZZ) sealing structure, and is widely used in various industrial equipment. Basic Dimensions Inner Diameter (d): 20 mm Outer Diameter (D): 37 mm Width (B): 9 mm Minimum Chamfer (r min): 0.3 mm Load Capacity Rated Dynamic Load (Cr): 6400 N (approx. 650 kgf) KOYO, some general-purpose models: 6350 N (6.35 kN) Rated Static Load (Cor): 3700 N (3.7 kN) Limiting Speed Grease Lubrication: 12000 r/min NTN, KOYO, general-purpose: 19000 r/min Oil Lubrication: 22000 r/min KOYO, general-purpose: 23000 r/min ⚠️ Note: Different brands have different definitions and test conditions for "limiting speed". Please refer to the specific brand's technical manual for actual selection. Other Key Parameters Weight: Approx. 0.037 kg Coefficient (f₀): 14.7 Stop Ring Groove (some grooved models such as 6904N/6904NR): Maximum Groove Diameter D₁: 35.7 mm Groove Width a: 1.7 mm, b: 0.95 mm Stop Ring Outer Diameter D₂: ≤39.8 mm Installation Dimensions: Shoulder Diameter da(min): 22 mm, da(max): 24 mm Outer Ring Shoulder Diameter Da(max): 35 mm Distance from Bearing End Face to Shoulder Dx: 40.5 mm
