×
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

Strain guage question

Strain guage question

Strain guage question

(OP)
I need to measure the negative strain after autofrettage (60,000 psi) of a thick walled vessel.

In the past, I have used special sealing glands to connect the strain gauges to the outside where I could record my data.  However, these were expensive and prone to problems.

Would it be viable to:
1)  install the strain gauges
2)  record the "zero" point
3)  disconnect the ohm meter from the strain gauge
4)  autofrettage the vessel
5)  measure the strain at the new strained condition

Is there anything wrong with my logic?

roadapple

RE: Strain guage question

If you know the response curve for that exact gauge, that would work very well.  We do the same thing for our vibration transducers -- attach a bunch, read them monthly.

RE: Strain guage question

(OP)
Not knowing much about strain gauges - why would the response curve be necessary?

Doesn't a particular resistance translate to a particular strain - in this case it would be negative.

 

RE: Strain guage question

You may need to use multiple SGs in case they get damaged in the process.
How do you calibrate your SG's?  This may be problematic with all of the handling.

= = = = = = = = = = = = = = = = = = = =
Plymouth Tube

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