Sealmaster Codes: How to Read Housing and Bearing Designations

Sealmaster codes combine letters and numbers to identify the product type, series, shaft size and features such as the locking system or material. For example, in a Y housing with insert bearing, the first letters indicate the housing series and the bearing type, while the numbers usually refer to the shaft diameter in millimeters or to a standardized designation.

Understanding this structure allows you to safely replace a part, compare alternatives and communicate precisely when requesting a quote. You don't need to memorize all codes: knowing the most common prefixes and suffixes is enough to identify most products.

Prefixes in Sealmaster codes identify the series or product type. For example, codes beginning with STM, TBM or SFM correspond to Y housings with insert bearing, each with different mounting or design features. The letter M usually indicates that the bearing is an insert type with set screw or eccentric locking.

For housings without bearing, the prefix PN is used to designate pillow block housings of the standard series. For spherical rollers, the same prefix PN appears in codes such as PN-206, PN-207 or PN-204, where the number identifies the size according to the standard series.

Knowing these prefixes helps you quickly filter the type of product you need and verify that you are requesting the correct part.

Numbers in Sealmaster codes usually indicate the shaft diameter in millimeters or a series designation. For example, in STMH-35, the number 35 corresponds to a 35 mm shaft. In Y bearings, codes such as MH-31, MH-19 or MH-23 follow a similar logic, where the number is associated with a specific shaft size.

Some suffixes may indicate additional features, such as the seal type or housing material. Although Sealmaster does not use suffixes like 2RS or C3 in the same way as other manufacturers, it is important to verify the complete designation to ensure compatibility.

It is always advisable to confirm the actual shaft size and working conditions before choosing a replacement, since the same number may correspond to different series depending on the prefix.

Let's look at some concrete examples from our catalog. The code STMH-35 corresponds to a Y housing with insert bearing, STM series, with 35 mm shaft. In the same subcategory, TBMH-27 and SFMH-24 are Y housings with insert bearing for 27 mm and 24 mm shafts respectively.

For housings without bearing, PN-22T, PN-32T and PN-39T are pillow block housings of the PN series, with different shaft sizes. In Y bearings, MH-31, MH-19 and MH-23 are inserts for different diameters. Finally, in spherical rollers, PN-206, PN-207 and PN-204 follow the standard series designation.

These examples show how the combination of letters and numbers allows you to quickly identify the product type and its main size.

To interpret a Sealmaster code, start with the prefix: identify whether it is a Y housing with bearing, a housing only, a Y bearing or a spherical roller. Then look at the number: in most cases it indicates the shaft diameter in millimeters or the dimensional series.

If you have a used part, look for the code engraved on the body or on the label. If it is not legible, measure the shaft diameter and the main dimensions of the housing or bearing, and compare with the reference tables. If in doubt, you can send us a photo of the part and we will help you identify the correct code.

Remember that the same number can appear in different series, so it is always important to verify the complete prefix and mounting features.

One of the most frequent mistakes is confusing the series by omitting a letter. For example, STM, TBM and SFM are different series of Y housings, even if the numbers are similar. Another mistake is assuming that the number is always the diameter in millimeters: in some cases it may be a series designation, as in the spherical rollers PN-206.

It is also common to confuse housings with and without bearing. A code PN-22T is only the housing, while an STMH-35 includes the insert bearing. Always verify what you are requesting to avoid buying an incomplete part.

Finally, do not ignore the suffixes: they may indicate the seal type, material or locking system, which affects performance and service life.

The Sealmaster code is usually engraved on the housing body or on the bearing outer ring. In Y housings, it may be on the base or on the side. In insert bearings, the code is on the outer ring, sometimes along with the serial number.

If the part is very worn or dirty, clean the surface with a cloth and look with good light. If you cannot find the code, measure the shaft diameter and mounting dimensions, and consult us with that data.

At MR Accesorios Industriales we work with the Sealmaster brand and we quote any code you need. Send us the code, the measurement or a photo of the part via WhatsApp or email and we will respond promptly.