Metric Size Miniature Ball Bearings

Metric size miniature bearings are single row ball bearings available from 1mm through 9mm bore sizes. The construction of these metric bearings enable them to carry moderate radial and thrust loads at low operating torque and provide high performance within a small envelope design.

Metric Miniature Ball Bearing Design Attributes

Types: Radial, Angular Contact, Full Complement, Thrust.

Metric radial miniature bearings can bear extremely high radial loads and small amounts of axial loads. Metric angular contact bearings can bear extremely high radial and axial loads. Metric full ball bearings are characterized by slow ultimate speeds, but they can bear the highest load.

Materials: Chrome Steel, Stainless Steel, Ceramic Hybrid, Plastic

Chrome steel is the most common material for metric ball bearings because it has characteristics of high load capacity and low noise. When there is a need for rust prevention, 440c stainless steel material is usually used.

Such kind of stainless steel material can bear both high load and high speed. Furthermore, it has the function of rust prevention. For higher speed requirements, silicon nitride ceramic balls are used to take the place of traditional steel balls.

Precision:  ABEC-1 to ABEC-9

Factors to be considered when choosing an ABEC grade include radial and axial runout requirements, bore and OD fits, and the audible noise level. Lily Bearing offer these types of grades which show the available selection of bore and OD size tolerances, and the radial runout limits for each. ABEC of Grades 3 is the first choice for routine applications. Typically, race finish and race geometry are superior in ABEC 5 and higher. These grades are generally recommended generally for precision assemblies where low noise, minimal runout, and long life are important considerations for metric miniature bearings.

Sizing: Smaller Than 10mm Bore Dia

Seal Type: Open, Sealed(Rubber Seals), Shielded(Metal Shields)

Open type metric miniature bearings are usually oil lubricated, with low starting torque and flexible rotation.

The standard metric bearing seal consists of nitrile/BUNA-N rubber bonded to a metal washer. The washer is made of SPCC cold rolled steel for metric chrome steel bearings or 304 stainless steel for metric stainless steel bearings. High temperature PTFE seals (up to 250°C) or Viton seals (up to 230°C) are available on some sizes. The inner lip of the seal rubs against the metric bearing inner ring to provide an effective seal against smaller particles such as dust and moisture while preventing lubricant leakage. Contact seals produce much higher frictional torque levels than shields and reduce the maximum speed of a metric bearing. Below -40°C nitrile rubber and viton will stiffen and provide a less effective seal so PTFE seals or metal shields should be considered for very low temperatures.

Shields are designed to prevent larger particles from entering the metric bearing and also to keep grease inside the bearing. They may be pressed into the metric bearing’s outer ring (non-removable) or retained by a circlip (removable). As the shields make no contact with the flanged extended inner ring, they do not increase starting or running torque. Shields on metric stainless steel bearings are generally made from AISI 304 stainless steel.

Cages: Crown, Ribbon, Rivet

Crown type cages: The stainless steel pressed cage is inner ring guided. It shows excellent performance in low torque, low speed applications.

Ribbon type cages: Consists of two mating steel pressings, the cover side and the finger side. Usually guided by the rolling elements and designed to reduce frictional torque.

Rivet type cages: The RJ type cage is suitable for larger metric miniature ball bearings with a high load carrying capacity. The two pieces are riveted together and are strong enough to withstand higher levels of vibration and acceleration. The cage is guided by the balls and reduces frictional torque.

Lubrication: Factory Lubrication From a Stock of Several Hundred Lubricants.

As the lubrication expert trusted by grease manufacturers，we know how important it is to find the right grease for your metric bearing application. With over 20 years of experience and knowledge, we are confident that we can match the best lubrication solution for our clients. What’s more, we can also use client-specified oil or grease lubricants.

Noise: Performance Testing For Noise And Friction Torque Specifications Available.

The standard instrument used for metric bearing noise testing is the Anderon Meter (sometimes called Anderometer) made by Sugawara Laboratories. This measures noise with an accelerometer contacting the outer race of the metric bearing while the inner race is rotated at 1800 RPM.

Temperatures:

Normal metric chrome steel bearings can be used at constant temperatures of 120°C or intermittent temperatures of up to 150°C. Above these temperatures, the load capacity of the chrome steel will be reduced. By means of special heat treatment processes and the addition of high temperature grease, we can also customize metric bearings for high temperature resistance.

Internal Clearance:

Internal clearance is the play between outer ring, inner ring and rolling element. Generally, the amount of up and down movement of the outer ring with respect to the fixed inner ring is called the radial internal clearance and its right and left movement the axial internal clearance. Bearing internal clearance in operation is an important factor that has a significant influence on other factors such as noise, vibration, heat and fatigue life.

Typical applications include:

Advantages & Buying and Using experience

Have been specializing in metric size miniature ball bearings for 22 years，our company is able to effectively deal with all kinds of difficulties encountered by our clients in bearing applications. In addition, our company has thousands of bearings in stock and can provide bearings which are rare in the market. We have rich experience in international trade, and most of our products can be shipped on the same day as the order is received. It is worth mentioning that we have much experience in serving US companies. According to statistics, 60% of our clients are from North America. For instance, Tesla, Google, NASA and other international famous companies are our loyal clients. They purchased our miniature bearings and spoke highly of them. Furthermore, our metric size miniature bearings are widely used in some world-class products. A case in point, our bearings have been used in the center console of Mercedes-Benz with s-series.

Our company is not only a seller of metric size miniature bearings, but also an expert in bearing solutions. We have a strong team of skilled engineers and a large service team, the mission of which is "client-oriented". Our experts have rich experience in serving end-users and well-established industry solutions, and can provide customized bearing solutions according to your actual working conditions.