AISI 304 stainless steel is widely used as a corrosionand heat-resistant steel and is also a nonmagnetic steel. It is most suitable in corrosive environments where AISI 440C stainless steel cannot be used.
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  1. Higher corrosion resistance than AISI 440C stainless steel bearings.
  2. Non-magnetic *.
  3. Heat-resistant temperature of standard specifications is the same as SS series.

[Difference in properties by the material used]

  Unit AISI 304 AISI 440C SAE 52100
Density g/cm3 7.93 7.8 7.8
Tensile Strength N/mm2 520-600 1900-2000 1680
Elongation 45-60
Elastic Modulus N/mm2 193000 203000 212000
Hardness HV 170 700 740
HRC 3.0 60.1 61.8
Magnetism Non magnetic Magnetic Magnetic

* AISI 304 stainless steel may be magnetized depending on manufacturing process.

Product Specifications

Standard Specifications
Inner and Outer Rings AISI 304
Balls*1 AISI 304
Retainer AISI 304
Shield AISI 304
Seal*2 Nitrile rubber
Lubricant*3 Heat-resistant grease
Precision Grade See “Dimensions”

The following special specifications are also available.
*1 Ceramic balls (Silicon nitride Si3N4)
*2 Fluorine rubber seal
*3 Heat- and chemical-resistant fluorine grease, food grade grease, and other special greases


●Food processing machinery, cleaning equipment, LCD and semiconductor manufacturing equipment, metal plating equipment, other equipment used in environments where the bearings come into contact with acid or alkaline chemicals.


For light load and low rotation. AISI 304 stainless steel is not suitable for use under heavy load or at medium to high rotation where SAE 52100 chrome steel and AISI 440C stainless steel are usable, due to the characteristics of the material.