The specification of cylindrical roller bearing models often poses a challenge for customers. Cylindrical roller bearings come in various specifications, categorized by whether the inner ring has ribs. They include NU, NJ, NUP, N, NF, and others for single-row bearings, as well as NNU and NN for double-row bearings. The diagram below illustrates the typical structure of cylindrical roller bearings with retainers.
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Common Types of Cylindrical Roller Bearing Models (Refer to the Diagram Above)
In addition to single-row bearings, there are double-row NN and NNU models, as well as four-row cylindrical roller bearings. While standard cylindrical roller bearings typically feature pressed steel retainers, those used for larger sizes or high-speed applications may employ brass machined retainers. Double-row or four-row cylindrical roller bearings often utilize pin-type retainers to extend their operational lifespan. Widely applied in gearboxes, pulley systems, printing machinery, and more.
![](https://www.good-bearings.com/wp-content/uploads/2024/02/8b725aa4525a74c93dc8f7978c43489.png)