We use cookies to provide you with a better experience. By continuing to browse the site you are agreeing to our use of cookies in accordance with our Privacy Policy.
  • TOPICS
    • Design
    • Manufacturing
    • Applications
    • Components
    • Industry
    • MRO
  • MAGAZINE
    • Current Issue
    • Departments
    • Archives
    • Subscribe
    • Advertise
  • NEWSLETTER
  • VIDEO
    • Power Transmission Engineering TV
  • BLOGS
    • Revolutions
    • Editors Choice
    • Motor Matters with George Holling
    • Bearings with Norm
  • BUYER'S GUIDE
  • NEWS and EVENTS
    • Product News
    • Industry News
    • Events
  • Advertising
    • Brand Awareness
      • Print: Display Advertising
      • Print: Engineering Showcase
      • Online: Web Banners & Keyword Banners
      • Online: Sponsored Content (Native Advertising)
      • E-mail: Custom, White Papers & Webinars
      • Email: Sponsored Content (Native Advertising)
    • Response & Lead Generation
      • E-Mail: Sponsored Content (Native Advertising)
      • E-mail: Newsletters
      • E-mail: Custom, White Papers & Webinars
      • Online: Buyers Guide
      • Online: Sponsored Content (Native Advertising)
    • Print
      • Print: Display Advertising
      • Print: Engineering Showcase
      • Print: IMTS/Hannover Messe USA Showstoppers (September 2022)
      • Print: Buyers Guide
      • Print: Engineering sMart
      • Print: Specifications
    • Online
      • Online: Web Banners and Keyword Banners
      • Online: Buyers Guide
      • Online: Sponsored Content (Native Advertising)
      • Online: Specifications
    • E-Mail
      • E-mail: Newsletters
      • E-mail: Custom, White Papers & Webinars
      • E-mail: Sponsored Content (Native Advertising)
      • E-mail: Specifications
    • Special Promotions
      • Print: Engineering Showcase
      • Print: Showstoppers(IMTS/Hannover Messe USA)
      • Print: Buyers Guide
      • Print: Engineering sMart
  • Contact Us
  • AGMA
    • Membership
    • Events
    • Education
    • Emerging Technology
    • AGMA Media
      • Gear Technology
      • Gear Technology India
    • Standards
Subscribe
  • Sign In
  • Create Account
  • Sign Out
  • My Account
Home » Blogs » Bearings with Norm » Aluminum Housing Series: Cup Distortion after Installation

Bearings with Norm
Bearings with Norm RSS FeedRSS

Design / Applications / Components / Gear Design / Power / Temperature / Steel / Bearings / Controls

Aluminum Housing Series: Cup Distortion after Installation

February 20, 2015
No Comments
The next step in our aluminum housing series is to determine where the cup interference is going. If we press a cup with 100µm interference into a solid steel block, most of that interference is going to compress the cup. If we press the cup into a block of jello, the cup isn’t going to compress at all. This is important to understand because the amount of cup compression plays a large role in the amount of preload you will lose with increasing temperatures.

You can find several variations of a bearing hoop stress/strain formula. I like the NSK version from their Technical Report; everything is in one table with the variables defined for an easy one-page reference. This table contains surface pressure, maximum stress and actual ring contraction. This is a cumbersome formula, but well worth your time to set up in a spreadsheet in lieu of running a CAE analysis or guessing. Plan on a ½ day in a quiet spot to get this set up with an example bearing. My advice is to break this up into steps in a spreadsheet. My spreadsheet has 29 cells just for the formula and another 6 for bearing dimensions.


norm32

All bearings are a little different, but for an easy example, a 100mm cup with a 100µm interference with a 20mm thick wall will have ~ 20µm of compression with the remaining 80µm expanding the housing. For this example, you have a 1:5 ratio of cup compression vs. housing expansion. If you set your target to be line to line fit at 120C (from 25C), at the halfway point, 47.5C, your cup should have expanded by 10 microns with the remaining press fit of 50µm.

Last week we covered how to target your press fit. This week we talked about the methods to find how much of that press fit goes into the cup vs. the housing. Next week, we will discuss exactly how to convert the radial bore expansion into axial preload loss. That won’t be your only source of preload loss, don’t jump the gun just yet.

If you don’t have NSK’s Technical Report, download it here for free: http://www.jp.nsk.com/app01/en/ctrg/index.cgi?rm=pdfView&pno=e728g

Post a comment to this article

Report Abusive Comment

Free Power Transmission Engineering Subscriptions
Subscribe
Free Power Transmission Engineering Subscriptions
Subscribe
FEATURED VIDEO
  • Regal Rexnord Motor Minute: Why Do Direct Drive Motor Shafts Have a Flat Side?
March 21, 2022
RECOMMENDED
  • LogiMat 2022 Offers Motion Control and Robotic Technologies

    April 18, 2022
    Logi1.jpg
  • The Flexibility Factor

    April 12, 2022
    Huco2.jpg
  • Rapid Advancement at Automate 2022

    April 12, 2022
    Depositphotos_204041702_XL.jpg
  • Interoperability: What it is, and why it matters in the age of automation

    May 17, 2022
    Kollmorgen1.jpg
  • The Extreme Ends of Turbine Condition Monitoring

    May 6, 2022
    wind farm1.jpg
  • Interoperability: What it is, and why it matters in the age of automation

    May 17, 2022
    Kollmorgen1.jpg
  • The Extreme Ends of Turbine Condition Monitoring

    May 6, 2022
    wind farm1.jpg
  • LogiMat 2022 Offers Motion Control and Robotic Technologies

    April 18, 2022
    Logi1.jpg
  • Subscribe
  • Advertise
  • Contribute
  • Gear Technology
Powered byAGMA
Copyright © 2022 Power Transmission Engineering
  • Privacy Policy
  • Contact