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EBL Extreme Bearing Spilt plummer block ss316

EXS Extreme Bearing pillow block stainless steel 316

EXG Extreme Bearing 3-hole flange unit ss316

EXP Extreme Bearing round 4-hole Flange Bearing unit SS316

EXT Extreme Bearing Take-up unit ss316

EBL Extreme Bearing Spilt plummer block ss316

EXS Extreme Bearing pillow block stainless steel 316

EXG Extreme Bearing 3-hole flange unit ss316

EXP Extreme Bearing round 4-hole Flange Bearing unit SS316

EXT Extreme Bearing Take-up unit ss316

EXW Extreme Bearing stainless steel 316 2-hole unit

EXC Extreme Bearing tapped base unit ss316

EXL Extreme Bearing 3-bolt bracket unit SS316

EXR Extreme Bearing SS316 Compact 2-bolts unit

Extreme Bearing thrust bearing ss316

Stainless Steel 316 RSBW 40 backstop clutch bearing with seal covers

Extreme Bearing Installation on an Adapter Sleeve (Spherical Roller & Self-Aligning Bearings)

Mounting a bearing with an adapter sleeve is technically one of the best mounting methods, providing a secure fit and excellent load-carrying performance. However, installation should be carried out by a qualified technician.

Before starting the installation, carefully read the mounting instructions and ensure that all required tools and components are available. Then follow the mounting procedure step by step to ensure correct bearing positioning, proper fit, and reliable operation.

Mounting Part name

  1. Housing
  2. Cover
  3. Cover seal
  4. Back seal
  5. Bearing
  6. Adapter sleeve
  7. Locating ring
  8. Oring
  9. Bolts
  10. Grease nipple
A pillow block housing is shown; the procedure also applies to other housing types.
seawater resistant bearing blocks

Preparations Prior to Mounting

Before mounting the bearing, ensure that the shaft is within the specified tolerance. An out-of-tolerance shaft may cause the adapter sleeve to deform the bearing inner ring, resulting in reduced bearing performance and service life.

  • Ensure that the shaft is clean and free from burrs, particularly those caused by set screws. Remove any burrs using a fine file. We recommend using a fine file rather than emery cloth, as this removes only the high spots without affecting the overall shaft tolerance.
  • Verify that the bearing seat diameter is within tolerance. Measurements should preferably be taken at three cross-sections, spaced approximately 20 mm apart, across the bearing seating area.
  • The recommended shaft tolerance is h9. For shaft diameters Ø35 mm to Ø40 mm, the tolerance range is +0.000 / -0.062 mm.
  • Check the shaft cylindricity using a micrometer at three positions around the circumference. The cylindricity tolerance should comply with IT5, with a maximum deviation of 0.011 mm.
Checking Shaft tollerances for mounting a bearing
Check the hardness and surface roughness of the shaft The hardness of the shaft should be a minimum of HRc 55. In general, shafts of carbon steel or stainless steel are most suitable. What’s even more important than a correct interference fit of the oil seal, is a perfectly smooth shaft in the region of the seal. The surface roughness of the shaft (Ra value) depends on the average profile depth of the tool marks caused by the machining process. For normal circumstances, the shaft in the region of the seal must have a surface roughness of approximately:

  • Ra = 0.4 to 0.8 mm
  • CLa = 8 to 25 mm
  • Rz = 1.0 to 4.0 mm
  • Rmax ≤ 6.3 mm
  • Ensure that the shaft and adapter sleeve contact surfaces are clean, dry, and free from grease, oil, dirt, or contamination.
  • Clean the support surfaces thoroughly and inspect them for damage, scratches, dents, or other surface imperfections that could affect mounting accuracy.

Built-in Clearance: A Unique Engineering Advantage

An Extreme Bearing assembly provides built-in clearance to accommodate thermal expansion and contraction in your machine design, ensuring reliable bearing performance under varying operating temperatures.

An Extreme Bearing Unit offers a unique advantage over conventional mounted bearing units. The units are supplied with an FRB locating ring, allowing the bearing arrangement to be configured either as a locating bearing, restricting axial displacement, or as a non-locating bearing, permitting axial movement to accommodate shaft expansion. This provides greater flexibility in bearing arrangement design and ensures accurate shaft positioning, controlled thermal expansion, and improved system reliability.

For optimal bearing performance and service life, it is essential to consider thermal expansion and contraction during the design phase.

  • Installation of the FRB Locating Ring

    All Extreme Bearing Units are supplied with an FRB locating ring as standard.

    In a typical bearing arrangement, one bearing unit is configured as the locating bearing and the other as the non-locating (floating) bearing:

    • Locating side: Install the FRB locating ring to prevent axial displacement of the bearing within the housing.
    • Floating side: Do not install the FRB locating ring. This allows the bearing to move axially and accommodate thermal expansion of the shaft.

    Since every Extreme Bearing Unit is supplied with an FRB locating ring, installing a bearing pair will normally result in one unused FRB ring. This spare ring may be retained for future use or disposed.

a Extreme Bearing unit is a prefect choose to be

Allow for Thermal Expansion and Contraction

The total clearance available for thermal expansion and contraction is equal to the thickness of the locating ring. Material expansion and contraction must be taken into account to ensure that sufficient clearance remains for proper bearing operation.

In the diagram, clearance C represents the available movement for contraction due to cooling, while clearance B represents the available movement for expansion due to heating.

The table below shows the maximum permissible values for C and B, depending on the shaft diameter.

 

Available for thermal expansion that is equal to the thickness of the location ring, FRB Bearing spacer
An Extreme Bearing assembly provides built-in clearance to accommodate thermal expansion and contraction in your machine design, ensuring reliable bearing performance under varying operating temperatures.
The effects of thermal expansion and contraction on a mounted bearing unit

Step-by-Step Assembly Guide for a Stainless Steel 316 Extreme Bearing Unit with an Adapter Sleeve

  1. Put some grease on the seal lip.
  2. Position both bearing units onto the shaft and bolt the bearing housing to the machine frame but do not tighten the bolts all the way yet.
  3. Check if the shaft has the correct level on the machine frame.
  4. Tighten the attachment bolts of the bearing housing to the frame.
  5. Measure unmounted radial internal clearance with
SS 316 Extreme Bearing with Adapter sleeve, whitout locking cover

Step 6 is unique because two different mounting methods can be used, depending on the application and positioning requirements.

Method 1 is the most commonly used mounting method and is suitable for the majority of applications.

Method 2 is intended for applications where a more precise bearing position is required. However, when highly accurate positioning is critical, a cylindrical bore mounting arrangement is generally recommended instead of an adapter sleeve. Adapter sleeve mounting can achieve accurate positioning, but the procedure is more delicate and requires careful execution.

6. Method 1, commonly used mounting method. As shown in the diagram (fig. 1), position the outer edge of the bearing race exactly level with the outer edge of the bearing housing to maintain inner bearing clearance after tightening the bearing adapter sleeve.
Measure the clearance required in the bearing assembly to accommodate thermal expansion and contraction.
Method 2, more precise bearing position. In case you want highly accurate axial positioning on the shaft, position only the bearing on the fixed side in the casing. As shown in figure 2, the position of the outer edge of the bearing race is not exactly level with the outer edge of the bearing housing after tightening the bearing adapter sleeve. This difference is indicated by A in figure 2 and the table shows the recommended values for A in mm depending on the diameter of the shaft.
7. First put some grease on the locking nut, both on the thread and the front surface.
8. Lift the shaft a little so that the bearing is free from load and the adapter sleeve can move freely.  
9. Place the locking ring in position and screw the lock nut onto the adapter sleeve with its chamfered side facing the bearing.  
tightening angle as given in the table for spherical roller bearings
10. Before starting the final tightening procedure, the bearing should be pushed up onto the tapered seat until the bearing inner ring cannot be rotated relative to the shaft. Then turn the nut through the tightening angle as given in the table for spherical roller bearings. Start the tightening procedure on the drive (fixed) side, never on both sides at the same time!
Use a hook spanner to properly tighten the lock nut when mounting a bearing on an adapter sleeve.
Download here the RADIAL INTERNAL CLEARANCE MEASURING instructions

11. During tightening of the KM lock nut, the bearing will be driven axially inward on the tapered seat of the adapter sleeve. If possible, the reduction in internal bearing clearance should be measured and checked by comparing the clearance before and after tightening the KM lock nut.

Verifying the clearance reduction helps ensure that the bearing has been mounted correctly and that the required interference fit has been achieved.

Using the MB Lock Washer with an Adapter Sleeve to instal a stainless steel bearing unit
Lock the nut in position After the correct tightening position has been reached, bend one of the outer tabs of the MB lock washer into the nearest slot of the lock nut. Ensure the tab is fully engaged in the slot to securely lock the nut. inspection Verify that the lock washer tab is properly bent into the lock nut slot. Check that the lock nut cannot rotate and that the bearing has been mounted correctly.
Heat-resistant Stainless Bearing units, type-E

12. Place the locating ring in position and then screw on the locking nut with its chamfer side facing the bearing.

13. Make sure that the O-ring is mounted properly.

14. Check that the shaft is not too long in case you want to use a closed cover seal. If you have a bearing for a drive situation, use an open cover with a shaft seal. In that case, put some grease on the seal lip and carefully push the seal over the shaft

15. If Method 1 was selected in Step 6, the shaft and bearing assembly should have approximately 1 mm of axial clearance in the backward direction when mounted on the locating (fixed) side.

If your application requires Method 2, where highly accurate axial positioning is necessary, verify the final bearing position after mounting. If the axial displacement exceeds the permissible limit, reverse Steps 6–14, adjust the bearing position as required, and repeat the mounting procedure.

Mounting the cover on a Extreme Bearing unit
16. After the bearing unit has been correctly installed and aligned, the cover can be mounted to protect the bearing assembly from contamination and accidental contact.

17. Fill the Bearing Unit with Grease

The bearing unit must now be filled with grease.

Slowly pump grease into the bearing unit while rotating the shaft or bearing by hand. Continue greasing until fresh grease begins to pass gradually through the seals without air pockets.

Do not pump the grease too quickly. Excessive greasing speed can trap air inside the bearing unit, causing grease to be forced out through the seals before the bearing is completely filled.

Proper grease filling is important to ensure adequate lubrication, prevent premature wear, and maximize bearing service life.

What is the recommended lubricant for the Extreme bearings?

As a bearing supplier, we cannot provide a definitive lubrication recommendation for every application. The most appropriate approach is to consult your grease supplier, as the selection of the correct lubricant depends on a variety of operating conditions.

Since the bearings used in our units are standard roller bearings, the lubrication requirements can vary significantly depending on the specific application. In addition, industry-specific requirements may need to be considered, such as FDA-approved greases for food processing applications or lubricants suitable for cleanroom environments.

The following factors should be considered when selecting a lubricant:

  • Temperature fluctuations – Bearings exposed to extreme heat or cold may require specialized lubricants to maintain performance.
  • RPM (rotational speed) – High-speed applications demand a grease capable of handling heat generation, while low-speed applications may require lubricants that remain effective under minimal movement.
  • Duty cycle – Intermittent versus continuous operation can influence the lubrication requirements.
  • Applied loads – Both axial and radial loads affect grease performance and service life.
  • Vibration and misalignment – These conditions can accelerate grease degradation or cause lubricant displacement from critical contact areas.
  • Environmental conditions – The operating environment, such as desert, underwater, offshore, or humid industrial applications, has a significant impact on lubricant performance and durability.
  • Compatibility with surrounding materials – The grease must be compatible with seals, elastomers, and other system materials to prevent deterioration or failure.
  • Chemical exposure – Applications involving aggressive chemicals, cleaning agents, or process fluids may require chemically resistant lubricants.
  • Humidity and moisture – Wet environments, particularly those involving freshwater, seawater, or frequent washdowns, require highly water-resistant greases.
  • Maintenance intervals – The availability of maintenance resources and the required relubrication intervals should be considered when selecting a lubricant.

In conclusion, the optimal lubrication solution depends on your operating conditions, environment, and performance requirements. We therefore recommend consulting your grease supplier to ensure that all relevant factors are taken into account and that the most suitable lubricant is selected for your application. Proper lubricant selection is essential for achieving maximum bearing performance and service life.