Stainless steel ball bearings are corrosion resistant when exposed to moisture and several other corrosive environments. Stainless steel ball bearings can be covered (with seals or shields) or open. Stainless steel ball bearings have a lower load carrying capacity than bearings of the same size made of chrome steel. Like all single row deep groove ball bearings, they have a simple and robust design. There are different types of stainless steel, and for stainless steel bearings, austenitic and martensitic are the most used types of stainless steel. The former has high corrosion resistance and the latter combines high hardness with a reasonable degree of corrosion resistance.
At AUB we stock SKF stainless steel ball bearings and economical alternatives. Stainless steel deep groove ball bearings are often used in the food and marine industries because the material does not rust. Stainless steel is resistant to water and other corrosive environments, making it ideal for applications where bearings may be exposed to any type of moisture. Although stainless steel ball bearings have a lower load carrying capacity than traditional chrome steel bearings, they otherwise have the same operating characteristics but are more environmentally resistant, which ensures minimal maintenance and reduces the likelihood of needing replacement.
| AISI 304 | AISI 440C | SAE 52100 | ||
| Specific Gravity | - | 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 HRC |
170 3.0 |
700 60.1 |
740 61.8 |
| Magnetism | - | Non Magnetic * 1 | Magnetic | Magnetic |
440C stainless steel bearings resist corrosion and provide exceptional hardness and strength. 304 stainless steel cage and guard; grooved raceways on inner and outer rings accommodate moderate axial and radial loads in both directions. Available in open, sealed (2RS) or shielded (ZZ). ZZ and 2RS can be pre-lubricated with FM222 H1 food grade grease.
| ZZ type | −40 ～ +150ºC/−40 ～ +302ºF |
| 2RS type | −30 ～ +110ºC/−22 ～ +230ºF |
| Open type | Subject to lubrication |
AUB manufactures a full range of corrosion resistant bearings, including stainless steel single row deep groove radial ball bearings. These ball bearings are forged from 440C stainless steel, the most common specification for the 400 series stainless carburized grade. This grade of stainless steel is heat treated to a Rockwell hardness of 58 for optimum wear resistance and service life. They are particularly effective in aqueous, corrosive, and abrasive environments; however, due to the carbon content of stainless steel, they may exhibit some surface film. Our stainless steel single row deep groove ball bearings feature double lip nitrile rubber seals and are most commonly used in high speed applications in the food, beverage and pharmaceutical industries. The double-lip nitrile rubber seal is effectively designed to not only prevent lubricants from coming into contact with the product being processed, but also prevent contaminants from entering the raceways and damaging the ball bearings.
316 Stainless Steel Ball Bearings.316 stainless steel contains chromium, nickel and small amounts of manganese and molybdenum, making it more resistant to chloride and salt environments. 316 stainless steel is resistant to most forms of oxidation. It is used in industrial applications with high levels of chemical exposure. 316 is also frequently used in saltwater environments and in medical and surgical equipment. AUB manufactures radial ball bearings from 316 stainless steel, which offers superior corrosion resistance compared to conventional 440 stainless steel bearings. 316 stainless steel is widely used in food, medical, marine industries. Bearings made of this steel can run in liquids or dry at low speeds. Machined semi-precision rings, polymer cages, and 100 grade 316 stainless steel balls are used to manufacture 316 stainless steel ball bearings.
| Carbon | Chromium | Nickel | Molybdenum | Manganese | Phosphorus | Sulfur | Silicon |
| 0.08% max. | 16% – 18% | 10% – 14% | 2% – 3% | 2.0% | 0.045% | 0.034% | 1.0% max |
304 stainless steel is widely used as a corrosion and heat resistant steel and also as a non-magnetic steel, best suited for corrosive environments where AISI 440C stainless steel cannot be used. In semi-precision grade bearings, 304 stainless steel can be selected for improved corrosion resistance above 440C. SS304 is not heat treated and therefore has significantly lower load and speed capabilities than HT 52100 and 440C. It is available in rings and balls or SS rings with ceramic balls. SS304 stainless steel has excellent resistance to aqueous corrosion and has excellent corrosion resistance when exposed to some common acids. SS304 is an excellent choice for food grade applications. Other applications may include marine and vacuum processes. 300 series stainless steel is also a common material for band and crown retainers. 300 series stainless steels are generally considered non-magnetic. Since SS304 stainless steel bearings are not as common as 440C, size availability and minimum order requirements apply.
Food and Beverage Industry: Typically used in equipment that comes into high contact with food because of their high corrosion resistance and ability to withstand high temperatures.
Marine and Offshore Applications: For applications that withstand harsh environmental conditions such as salt water, humidity, and corrosive materials.
Chemical and pharmaceutical industry: for handling highly corrosive liquids and chemicals.
Mechanical Medical Equipment: Used to provide smooth and accurate .
Rubber seals (RS/2RS) for optimum sealing action with increased friction. Metal seals (Z/ZZ) are suitable for higher speeds, but their sealing effect is limited because they are non-contacting seals. Open unsealed bearings are suitable for very high speeds, and - they can be re-lubricated more easily. However, they are more likely to get dirty.Proper lubrication and maintenance are essential to ensure the life and performance of stainless steel ball bearings. Reduce wear and friction by lubricating bearings with the right lubricant for the application. Also, it is important to keep the bearings clean and handle them with care to prevent damage. A maintenance plan should also be developed to ensure regular inspection and maintenance of bearings.
Stainless steel ball bearings are key components in a variety of equipment and machines. Known for their high performance and durability, stainless steel ball bearings are very common in a variety of industries.
Corrosion Resistant: An ideal solution for harsh environment applications where other bearings are prone to rust or other forms of corrosion.
Durability: can withstand heavy loads in challenging conditions
Low Friction: Extends service life and minimizes wear through low friction design
Versatility: Offers high precision and versatility for use in a variety of applications
Stainless steel ball bearings are versatile and efficient solutions for a wide range of applications. With their high corrosion resistance, durability and low friction, they are ideal for many industries. However, proper maintenance and lubrication are essential to ensure their longevity and performance. If your equipment requires bearings, consider stainless steel ball bearings because of their many benefits and applications.
Compared with ordinary chromium steel bearings, stainless steel bearings not only have obvious advantages in material, but also have much stricter process and precision control than ordinary chromium steel bearings. During the working process, the stainless steel bearings work smoothly, have low noise, are corrosion-resistant, and are widely used.