×
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

Gear box misalignment

Gear box misalignment

Gear box misalignment

(OP)
Could anybody give information about how a misalignment in the gearbox is checked? I have one double speed constant mesh gearbox where failure has taken place due to misalignment as only one side of teeth have broken on one gear, 26T, 12DP, 23 Deg Helix.  

RE: Gear box misalignment

One way is a soft blue check under partial load.

RE: Gear box misalignment

Clean the teeth and paint with layout dye from Dykem. You will have to experiment with how long to run for a good pattern check, depends on oil film thickness. If the paint film rubs off too quickly, you will be looking at a composite of deflections as you are comming up to the load being checked. Try to get the reading to take an hour or so.

To slow the reading, run cooler and thicker oil, oppisite to speed up. The idea is to read the contact at the load being investigated.

We have found red dye to work well, though blue or even white is OK.

Constant mesh gears, running on a bore bearing, will tip due to over-turning moments. This may be the problem.

RE: Gear box misalignment

what will be your solution if you find that you have a misalighment????
have you changed gears in the gear box and got a misalignment subsequently? then it is due to helix angles not matching
if it is a new gear box talk to the manufacturer

RE: Gear box misalignment

You can check alignment as per the good advice you've been given.
This may sound somewhat basic but have you checked:
# The shaft design for deflection and angle of deflection at the gear. Poor shaft design can result in gross misalignment under load.
# That the bearing type and arrangement is correct. i.e correct clearances, allowance for thermal movement/float
# Is the gearing symetrical?. As the gear heats up under load will both sides of the gear expand at the same rate?.
# Is the gear running true on the shaft.(mounted properly)
# Has the gear shifted on the shaft?
# Does the gear casing temperature have any effect on alignment?.
# Does the gear casing distort under load.?
# Is there an external overhung load on the shaft that could impact on alignment?. i.e. a different position of the shafting as made possible with actual bearing clearances.
  

RE: Gear box misalignment

(OP)
beloka , I appreciate your advice. I would double check .

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