Facebook Twitter LinkedIn YouTube Menu Search Arrow Right Arrow Left Arrow Down Arrow Up Home Arrow Next Arrow Previous RSS Icon Calendar Icon Warning Icon
NEED TO RENEW MEMBERSHIP?  RENEW NOW

Filter the results

  • Enter one or more words to find resources containing any of the words entered
  • Enter words or phrases between " " to find exact match

Resource Library

Article

The quest to find the perfect bearing fit

  • October 2010
  • Number of views: 1324
  • Article rating: No rating

Jim Bryan
EASA Technical Support Specialist

Much has been said and much work performed to produce the “perfect” bearing fit. For any single bearing, there is an inner fit to the shaft and an outer fit to the housing. It is required that one of the two fits be able to slide in order to assemble the machine. If the bearing-to-shaft fit (journal) is tight, then the bearing-to-housing (bore) must be loose. Of course tight and loose are relative terms and the quest for the perfect fit must define these terms.

A tight fit, also known as an inter­ference fit, is usually recommended for a motor bearing journal. The range for radial ball bearing journal fits is from j5 to m5, and the housing fit is H6 (see Table 1). These are the “standard” fits and may be different depending on the machine design­ers understanding of the application. Table 1 is derived from Table 2-13 of ANSI/EASA AR100 Recommended Prac­tice for the Repair of Rotating Electrical Apparatus. It shows the relationship of bearing size to fit tol­erances. Generally, as the bearing gets larger, the tolerance widens. The key to this chart is that the journal fit is always interference and the bore fit is always line-to-line to loose. See AR100 for additional radial ball and roller bearing sizes.

LOGIN TO VIEW AND DOWNLOAD THE ARTICLE



Categories: Bearings
Tags: Bearings
Rate this article:
No rating
Print


PREVIOUS ITEM
Comments are only visible to subscribers.

Getting The Most From Your Electric Motors

Getting The Most From Your Electric Motors - coverThis 40-page booklet provides great advice for obtaining the longest, most efficient and cost-effective operation from general and definite purpose electric motors.

This booklet covers topics such as:

  • Installation, startup and baseline information
  • Operational monitoring and maintenance
  • Motor and baseline installation data
  • How to read a motor nameplate
  • Motor storage recommendations

LEARN MORE AND DOWNLOAD MÁS INFORMACIÓN Y DESCARGAR BUY PRINTED COPIES

READ MORE ABOUT THE FEATURES AND BENEFITS

EASA/AEMT Rewind Study

EASA Rewind Study cover

The Effect of Repair/Rewinding on Premium Efficiency/IE3 Motors
Tests prove Premium Efficiency/IE3 Motors can be rewound without degrading efficiency.

DOWNLOAD THE FULL RESULTS

ANSI/EASA AR100-2020

ANSI/EASA AR100-2015 cover

Recommended Practice for the Repair of Rotating Electrical Apparatus
This is a must-have guide to the repair of rotating electrical machines. Its purpose is to establish recommended practices in each step of the rotating electrical apparatus rewinding and rebuilding processes.

DOWNLOAD - ENGLISH

DESCARGAR - ESPAÑOL

EASA Technical Manual

EASA Technical Manual cover

Revised May 2021
The EASA Technical Manual is the association's definitive and most complete publication. It's available FREE to members in an online format. Members can also download PDFs of the entire manual or individual sections.

VIEW & DOWNLOAD