×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

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!
  • Students Click Here

*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

Jobs

Motor Housing

Motor Housing

Motor Housing

(OP)
Hi all,

I was told that the motor housing plays a part in containing the magnetic flux generated when the 3 phase volatge is applied to the stator. Is this true?

If there is a hole in the housing (happened actually, I ahve this motor which is exposed to acid and the acid actually burnt a hole in the housing, luckily the stator was not affected), and the hole is not covered properly, will it affect the performance of the motor?

Thanks in advance!

RE: Motor Housing

czping

It may effect the cooling and leave the motor more susceptible to contamination.  The magnetic circuit is within the stator. If the stator, which is iron holding the windings, is not dissolved it shouldn't effect the operation unless the cooling is somehow compromised.

Best Regards

Ray Micallef, P. Eng.
Power Generation/Utility Industry

RE: Motor Housing

I don't think in this case that motor performance will be changed much. However the motor housing contributes to and acts as parts of the stators "back iron".Some years ago we looked at changing to aluminum housings but couldn't live with the changes to the speed torque curves.

RE: Motor Housing

(OP)
ERaySir

Thanks! So, if the stator is not damaged, and there is a hole in the housing (presume that nothing is falling into the housing), it should perform as good as ever?

Then we do some people have the idea that the flux cannot be contained? Do you think it is applicable to some other cases?

RE: Motor Housing

Suggestion: It depends how big that hole is. If it is small, and away from bolts or screws, then it will have a small effect on the motor performance. It would be more practical to cover the hole since there may be a very little protection left to the stator windings.

RE: Motor Housing

(OP)
Hi Jclough,

I do not understand your statement: "changing to aluminum housings but couldn't live with the changes to the speed torque curves". Is there a change in the characteristic to the motor?

For your information,I actually cover the hole in my motor housing using a steel plate, so far it is running ok. The size of the hole is about 5cm in diameter.

RE: Motor Housing

DC motors nearly always use the frame as part of the magnetic circuit, regardless of size.  This is because the stator field is virtually static.

However AC motors ideally do not use the frame as the field is alternating and requires the iron to be laminated to reduce iron losses.  Inevitably though there will be some leakage of flux into the frame if it is iron or steel, and this could have a marginal effect on performance (particularly if the designer was cutting corners a little to save on lamination material).  But if the 5cm hole is small relative to the overall size, or if the frame is aluminum anyway, then don't worry about it.

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!


Resources