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

Hey guys I would just like to know

Hey guys I would just like to know

Hey guys I would just like to know

Hey guys I would just like to know the reason for the term HOT PASS in welding i.e the second pass after the root pass.

RE: Hey guys I would just like to know

Hot pass is a term which originated with pipeline welding. In pipelines the root pass is mostly applied using downhill welding and cellulosic electrodes. Now cellulosic electrodes need high misture to the tune of 5-10% if I remember correctly to hold the cellulose together, which means the hydrogen in weld metal of root pass is also very high. The second pass in such cases is deposited within a very short time of depositing the root pass typiclly three to five minutes. So the root is still hot when the first fill pass deposited. So the root pass hydrogen gets time to diffuse out, the root pas gets tempered, and defects in the root pass get burned out. That is why the first fill pass is normally called hot pass because it is deposited when the root pass is still hot.

Thanks and regards
Sayee Prasad R
Ph: 0097143968906
Mob: 00971507682668

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