How to Read Timken Codes: Designation Structure, Prefixes, Suffixes, and Real Examples

Timken codes follow a logic that combines numbers and letters to indicate type, series, dimensions, and specific characteristics. Although each manufacturer has its own system, Timken maintains a structure recognizable in the industry. Understanding it allows you to quickly identify a bearing and verify if it is compatible with your application.

In this guide, we show you how the most common designations are assembled, what prefixes and suffixes mean, and how to use that information when requesting a quote. We work with the Timken brand in Buenos Aires, Argentina, and help you find the exact code you need.

A typical Timken code can be divided into three parts: a prefix (optional), a base number, and one or more suffixes. The base number usually indicates the dimensional series and bore size, while suffixes add information about internal design, cage, seals, or radial clearance.

For example, in a tapered roller bearing such as 2879, the number identifies a specific series with dimensions defined by standard. In a spherical roller bearing such as 22313EJ, the base number 22313 corresponds to series 223 with a 65 mm bore, and the suffix EJ indicates a particular cage and roller design.

Not all codes have a prefix; many start directly with the number. Prefixes usually appear in special series or in housings, such as LSM55 or MSM90, where the initial letters identify the housing type and the number the shaft diameter in millimeters.

Timken tapered rollers are among the most used in the industry due to their ability to support combined loads. Their designation is usually a series number followed by a suffix indicating the angle or internal design. For example, 2879, 414A, and 432A are real codes from this subcategory.

In these codes, the letter A may indicate a modification of the original design or a specific contact angle. The numeric series defines the outer diameter, width, and bore, following international standards. It is important to verify the complete code, including suffixes, to ensure interchangeability.

When you need to replace a tapered roller bearing, it is advisable to have on hand the code engraved on the part or on the equipment plate. With that data, we quote the corresponding Timken option without confusion.

In Timken spherical roller bearings, the most common suffixes are EJ and EM. For example, 22313EJ and 22214EJ carry the suffix EJ, while 22310EM carries EM. The letter E indicates an optimized design with higher load capacity, and the J or M refers to the cage type: J for stamped steel cage and M for machined brass cage.

These bearings are used in applications with misalignment or heavy loads, such as transmission shafts, fans, or mining machinery. The complete designation is key: a 22313EJ is not the same as a 22313EM, because the cage and performance change.

If you have doubts about which suffix to choose, we guide you according to the application and load conditions. We stock the Timken line of spherical roller bearings and help you interpret the code.

Timken housings have a different nomenclature: they combine letters indicating the housing type and numbers that usually refer to the shaft diameter in millimeters. For example, LSM55 and MSM55 are housings for a 55 mm shaft, while MSM90 is for 90 mm.

The initial letters identify the series: LSM and MSM are common series of pillow block housings with insert bearing. In addition, Timken offers adapter and withdrawal sleeves, such as AN-21, AN-20, and RN-28, which follow a pattern of letters and sequential numbers.

For these products, the complete code is essential because it defines the size and mounting type. If you have the code or shaft measurements, we quote the appropriate Timken housing or accessory.

Timken deep groove ball bearings use simple numeric codes, such as 6301, 6202, and 6004. The first digit indicates the series (6 for single row deep groove ball bearings), the second the width series, and the last two the bore diameter in millimeters multiplied by five (for example, 04 = 20 mm).

These codes can have suffixes added, such as 2RS (rubber seals on both sides) or C3 (radial clearance greater than normal). Although the listed examples do not include suffixes, it is common to find sealed or special clearance variants in specific applications.

If your bearing has a suffix, do not omit it when requesting a quote: it can change the lubrication type, protection against contaminants, or internal fit. We help you identify the correct variant.

At MR Accesorios Industriales, in Buenos Aires, Argentina, we stock the Timken brand in its main subcategories: tapered rollers, spherical rollers, housings, deep groove ball bearings, sleeves, and accessories. We work with the exact codes listed in the Timken catalog.

To request a quote, send us via WhatsApp or email the complete code (for example, 22313EJ), the bearing measurement, or a photo of the part. With that information, we will provide you with a quote shortly and indicate the alternative if there is any variant.

You don't need to be an expert in nomenclature: tell us what equipment it is and what bearing it uses, and we will take care of interpreting the code and offering you the correct Timken option.