Contact US

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!

*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

Max bend radius of innerduct thru pipe bend

Max bend radius of innerduct thru pipe bend

Max bend radius of innerduct thru pipe bend

Should be fun for hard-core math types. An innerduct of outside diameter d, runs inside a 4" IPS pipe (0.188" wall).  Said pipe makes a 90 degree turn.  The elbow used is a long radius, i.e. bend radius of 1.5R or 6".  What is the maximum bend radius in inches of the innerduct that traverses this pipe bend (assume a smooth curve with tangent line going in one direction only).  Contention is that max occurs when half way through bend innerduct touches inside wall of pipe bend, and that bend radius of innerduct is larger than bend radius of pipe, even at outside wall.  General formula result also invited.  Thanks!

RE: Max bend radius of innerduct thru pipe bend

OK, I took a shot at it.  I come up with a maximum bend radius of almost 18", more than double the bend radius of the pipe at its outside wall.  If anyone is interested and kind enough to either confirm or suggest a different answer, i would be grateful.  Thanks!

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! Already a Member? Login


Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close