×
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

Sag Mill High Vibration - Highest Motor NDE White Metal bearings

Sag Mill High Vibration - Highest Motor NDE White Metal bearings

Sag Mill High Vibration - Highest Motor NDE White Metal bearings

(OP)


On site we have a Sag Mill Driven by a 5500KW Motor. We have a vibration issue right across the Mill. The highest vibration is 30mm/sec RMS axial on the motor non drive end bearing.(White metal Bearing)
The gear mesh frequency is 4200 CPM. The dominant frequency is 2400 CPM. We can not relate this to anything on the Mill or drive train but with the high energy vibration the number 1 suspect is the 5500 Kw motor but need something to confirm this
The vibration has high energy vibrating platforms etc. Where ever I take velocity measurements the dominant frequency is 2400 CPM . Measurements on the pinion bearings motor bearing , trunion bearings, the concrete foundations etc.
As mentioned the highest measurement is the motor non drive end axially 30mm/sec . This is a synchronis motor 200RPM . 200RPM 30 pole motor 50Htz

We have inspected pinion bearings ,the air clutch, covers removed from motor for a visual check. Nothing found.The pinion and girth gear yes are worn but thermo graphic and visual visaul indicates this is not the issue.

I believe the vibration is coming from the motor possibly at a coil pass frequency which I have read has high energy vibration.
I am in a very isolated ara and hard to get access to specialists.
I am trying to get the name plate information and hoping someone has photographed it in the past
Have a look at the attachment with spectrum and an overall model of the Mill Vibration
Has anyone had a similar experience. Is it possible to have a coil pass pass frequency of 200 x 12 to = 2400CPM .
Very hard to get information about this motor. It is a GE Canada Electric motor . I have attached a data sheet.
I would appreciate any feed back or indications where to look.
Find the 12 x 200 RPM shaft speed we find the issue
All help would be highly appreciated

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