×
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

Die Swell

Die Swell

Die Swell

(OP)
Hi,

Could you give some information that How can I measure die swell diameter without using laser sensor.? Could you advise
an apparatus for this aim?

 Thanks a lot

RE: Die Swell

The laser is the best way. You can cut extrudite as it exits the die and then measure the diameter but there will be should error as the polymer will cool and change dimensionally. The polymer must also have enough melt strength as it exits the die for this to be approximated.

Compare the diameter of the die orifice with the extrudite diameter.

RE: Die Swell

(OP)
Hi plastx,

Firstly ,thank you very much .I have interested in this area resently.According to the your reply,I think that you are experienced on this area.If you give permission,I want to ask a question.
I will calculate viscosity and other parameters of polymers without using a software.So my job is very difficult,I think.I will mount a pressure thansducer above the die to measure pressure drop inside die.And then I will use bagley correction.But orifice die also can be used for this.What is the better method to measure the pressure drop in capillary ?

RE: Die Swell

My experience has been using a rheometer that had the software that calculated the Bagley correction. There is a way of manually calculating but I don't have the formulas. They might be available on the web somewhere. The calculations rely on a "zero-height" die which would then have no pressure drop in theory. Thus having a very short die and a longer die (same orifice diameter), run the same rheometer conditions (speed, temp, timing) and compare the results.

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