Start by breaking down the code on your bearing into 3 parts
If you are looking for more details, kindly visit our website.
Bearings very rarely have a prefix code. However, you may come across one that does. The prefix is used to highlight the parts used by the manufacturer in the design of the bearing. In our example where we have a Prefix of (S) it tells us that the bearing was made using stainless steel. Below are a couple of common examples
Prefix
Meaning
The first digit of the basic number tells you about the type of bearing you have. In our example, its (6) So this tells us its a Single row deep groove ball bearing.
Bearing Type Code
Bearing Name
The second digit of the basic number tells us what series the bearing is from and is used to signify how tough the bearing is. In our example, its (0) Which tells us its extra light toughness.
Series Code
Series Code Meaning
The third and fourth digits tell you the bore size or (ID) of the bearing you have. In our example, its (0) which tells us the bearing has a 12 mm bore size.
Important Note that from 20mm and above you would need to times (x) the last 2 digits by 5 to ascertain the bore size for nearly all types of bearing.
Third and Fourth Digit
Bore Size (mm)
Suffixes indicate bearings with additional special characteristics or designs. They are typically used to provide information about how the bearing is sealed. In our example, its (2RS) which tells us our bearing is sealed on both sides.
Suffix
What do they mean?
In some cases, your bearing may have an additional suffix such as C3. This can be found on the outside diameter of the bearing except in the case of CN. This refers to the bearings clearance code. See the table below for examples.
If you need to source a replacement bearing, you may be wondering how to measure a bearing.
Often, bearings are measured in the event of a bearing failure, meaning that there is a rush to identify the bearing type and size so that a replacement can be ordered. This can lead to mistakes being made and further downtime and costs being incurred.
Measuring a bearing doesnt need to be complex. Weve put together the ultimate guide to measuring a bearing, to give you the confidence that you need to accurately measure and identify your bearings.
skf are exported all over the world and different industries with quality first. Our belief is to provide our customers with more and better high value-added products. Let's create a better future together.
Read on to learn how to measure a bearing quickly and accurately.
When should you measure a bearing?
The most common time that youll need to measure a bearing is after a bearing failure. When your bearing fails, youll need to quickly establish the size and type of bearing before you can order its replacement.
Whilst most bearings have their reference numbers laser stamped or engraved into them, these numbers often rub off over time. If youre unable to read the reference number on the side of your bearing, youll need to measure the bearing to determine its size.
Once youve established the type and size of bearing, you can choose to order a like-for-like replacement, or to upgrade your bearings to potentially extend their service life.
To source a replacement bearing, youll need to take three different measurements. These measurements include:
Providing you also know what type of bearing you have, for example an SKF deep groove ball bearing or an NSK needle bearing, youll be able to order a like-for-like replacement using these measurements.
To measure the size of your bearing, youll need a vernier calliper. This is the most accurate way to measure a bearing.
If you dont have a vernier calliper available, it is possible to measure your bearing with a good quality steel ruler, but its a good idea to check your measurements a couple times to ensure that they are accurate.
Read on to discover how to measure each part of your bearing.
The inner diameter (ID) of a bearing is also known as the bore diameter. This is the measurement of the diameter inside the bearing. To find the inner diameter of a bearing, you need to measure from one side of the inner ring to the other.
To measure the inner diameter of a bearing, insert the outer anvils of your vernier caliper into the bore and open the caliper until it meets the inner bore of the bearing. Now, you can read the value on the caliper to find the inner diameter measurement.
If you dont have a vernier caliper, use a high-quality steel ruler to carefully measure the inner diameter of the bearing. Repeat this three times to ensure that the measurement is accurate.
The outer diameter (OD) of a bearing is the measurement of the total diameter of the bearing. To find the outer diameter of a bearing, youll need to measure from one side of the outer ring to the other.
To measure the outer diameter of a bearing, place the jaws of your vernier caliper around the outside of the bearing and close it until it meets the outer edge of the bearing. It should be a snug fit, but not tight. Now, you can read the value on the caliper to find the outer diameter measurement.
Like with the inner diameter, if you dont have a vernier caliper, you can use a high-quality steel ruler to carefully measure the outer diameter of the bearing. You should repeat this three times to ensure that the measurement is accurate.
The bearing width refers to the width of the outer ring. This can be measured in the same way as the outer diameter. Simply place the jaws of your vernier caliper around the width of the outer ring of the bearing and close it until it meets the ring. Again, it should feel snug but not tight. The value which is displayed on the caliper is the width of the bearing.
Whether you measure your bearing in inches or millimetres will depend on whether your bearing is imperial or metric. Imperial bearings are measured in inches whilst metric bearings are measured in millimetres.
One way to determine whether you have an imperial or metric bearing is to measure it. Most bearing sizes will be a full mm or inch measurement. So, if your bearing is metric, the measurement will be a full mm, for example 9mm. If your measurement is 9.5mm, its likely to be a 3/8 inch imperial bearing.
Once you know what size bearing you need, you now need to establish which type and brand of bearing is best for your application. You might choose to do a like-for-like replacement, switching your bearing out for an exact replacement. However, wed always recommend using bearing replacement as an opportunity to see if there is a bearing which is better suited to your application.
Not only will using the optimum bearing improve the running characteristics of your application, but it can also improve your energy efficiency and help to prevent premature
If you want to learn more, please visit our website Thrust Roller Bearings.