Contact US

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Relation - Internal Clearance to Press Fit

Relation - Internal Clearance to Press Fit

Relation - Internal Clearance to Press Fit

Having a Bearing like 35 x 62 x 14 with internal clearance about 0.012 how can I make a relation to Press Fit TOLERANCE on ID
How much press fit is too much ? to kill the internal clearance ...
That is not my goal at all but the press fit can be calculate with relation to internal clearance ?

RE: Relation - Internal Clearance to Press Fit

I suppose you could look at the outer race thickness and do a calculation. Your bearing manufacturer, though, should have that info for you.

RE: Relation - Internal Clearance to Press Fit

Most of the thicker bearing catalogs talk to this.
First, they will have recommended housing and shaft Diameter tolerances based on loading, application etc.
Does for some reason your application require shaft diameter other than k5 fit ? ( nominal +1 to +17 um ?

I think in the thickest bearing catalogs, with major engineering sections, you may read there is a general relationship around 80% between diametral interference and diametral clearance lost.

RE: Relation - Internal Clearance to Press Fit

The reduction of clearance caused by an interference fit is something available in the bearing engineering books.

The rule of thumb I use is 80% of the interference between the inner ring and the shaft will become the reduction of clearance in the bearing.

In your example, the 35 x 62 x 14 mm bearing is most likely a 6007 deep groove ball bearing.

The bearing inner ring bore has by ISO standards a diameter of 34.988 to 35.000 mm.

A k5 machining tolerance applied on a 35 mm shaft means the shaft is 35.002 to 35.011 mm.

This means the interference between the inner ring and the shaft, when the bearing is mounted on the shaft, is between 0.002 and 0.023 mm.

80% of this interference is 0.0016 mm to 0.0184 mm. This is the amount of clearance reduction in the bearing from the action of installing the bearing tight on the k5 machining tolerance shaft.

A normal clearance class 6007 bearing has a radial internal clearance range of 0.006 to 0.020 mm.

Applying the reduction of 0.0016 to 0.0184 mm to this clearance range, you may end up with a final clearance after mounting ranging between -0.0124 and +0.0184 mm. A negative clearance indicates a preload.

You can therefore see that due to manufacturing tolerances of the bearing bore, radial internal clearance, and shaft, you could end up removing the entirety of the clearance in the bearing.

Many high speed applications, like electric motors, suggest a standard clearance class of C3 for ball bearings, since the high speed operation reduces the clearance further.

A C3 clearance class 6007 bearing has a radial internal clearance of 0.013 to 0.028 mm.

If we were to apply the same reduction (from the k5 machining tolerance shaft) of 0.0016 to 0.0184 mm, the end result for the C3 bearing is a clearance range between -0.0054 mm and 0.0264 mm.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close