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FAQ
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FAQ

  • What is the recommended end play for tapered roller bearings?

    End play is application specific, or preset in the case of NA type tapered assemblies. The machine manufacturer's recommendations should be followed.

  • Some Part of the Bearing (Inner or Outer or Both) is appearing grey in colour. Is it a good bearing?

    This process is called "Black Tempering". To check the physical damage or minor cracks, a sample lot of bearings from a particular batch are coated with special chemicals to check any such damages. Such Chemical coating helps in detecting very minor defects and cracks which can not be detected otherwise. Such colour has no influence on the quality or tolerance of the bearings. It is nothing but a standard bearing only.

  • What is the fan bearing?

    The major function of fan bearing is to make fan blades operated fluently. The purpose of fan bearing is to reduce rotational friction and support axial loads. The fan bearing is the most critical factor in fan lifetime and fan performance. Without fan bearing, a cooling fan cannot work. When choosing a cooling fan, it considers not only airflow and static pressure but also the reliability of fan itself. It determines if a cooling fan can run consistently many years. The fan bearing is the critical role of fan.

  • What is the advantage of a ball bearing without a retainer or cage?

    Bearings without a retainer are called full complement bearings. This is because they have more balls which allows them to take heavier loads. They also cope with sudden shock loads (impact loads) as the increased number of balls distributes the load across the bearing raceway more effectively.
     
    It is only possible to fit extra balls to this type of bearing thanks to a filling slot. This is created by machining a groove in the inner ring and outer ring. When these are matched up, it is possible to press extra balls into the bearing. Full complement bearings are less popular now as improvements in steel technology allow standard bearings to take much greater loads than before.
     
    Full complement bearings are only suitable for very light axial loads due risk of the balls being forced out of the filling slot. Speed ratings are much lower than those for bearings with a retainer as a full complement bearing experiences additional friction as a result of the balls rubbing against each other (ball to ball friction). An exception to this is a full complement bearing with ceramic (usually silicon nitride) balls thanks to the much lower friction coefficient of the ceramic material.
     

  • What are the design differences between radial and angular contact ball bearings?

    The main difference between radial ball bearings (fig. 1) and angular contact ball bearings (fig. 2) is the retainer type: radial bearings include a crown retainer (fig. 1) whereas angular contact bearings include a full retainer (fig. 2).
    ball bearing

  • What are the benefits of ceramic bearings?

    The benefits of ceramic bearings are that they do not rust. They are self cleaning, lighter than metal, and durable. They also can withstand higher speeds & acceleration capability. There is less heat friction, and they have a higher spin rate. 

  • Can lubricants be mixed?

    We do not recommend mixing greases. Mixing incompatible greases can result in the mixture hardening, preventing it from releasing any of the oil. Mixing incompatible greases can also soften the mixture, which will release all of the oil. Either case will result in a mixture than cannot properly lubricate a bearing. We highly recommend using the same type of grease that was originally supplied with the bearing.

  • What is the difference between using a shield or a seal as a ball bearing closure?

    Shields or seals are often installed to retain lubricant and to prevent contamination from entering the bearing. While a shield contacts the outer ring and does not come in contact with the inner ring, the seal generally comes in contact with both the inner and outer rings. Torque or drag is lower with a shield than with a seal. Alternately, the seal provides a higher degree of protection from contamination. Shields and seals are available in a variety of materials and configurations.

  • What do bearings for roller skates do?

    The bearings help the wheels move freely on the skate. Generally, the higher "rated" the bearing the better the bearing. However, most non-professional or non-competitive skaters will not need anything above standard skate wheel bearings.

  • How does the radial load compare between steel, ceramic hybrid and full ceramic bearings?

    The ceramic hybrids can handle the same loads as a steel bearing and full ceramics can handle 10-15% less than steel. The full ceramics are not as tolerant as steel to shock loads or excessive vibration.