×
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

Seamless versus seamed tubing

Seamless versus seamed tubing

Seamless versus seamed tubing

(OP)
Can someone please tell what the differences are between seamless and seamed tubing?  What I mean is are there applications where one type will work better than the other?  Are pressure ratings different?  Does anyone know of any technical articles or websites that deal with this?  Thanks for any help.

RE: Seamless versus seamed tubing

namartin, The identfications seamless or welded/seamed identfiy the manu'f. methods of the product. Seamless is pierced and swaged, where as welded, is rolled and the seam is then welded. There are differences in the pressure and temprature ratings of the two types. Sort of like the difference between copper and aluminm wire. Go to the following site: www.swagelok.com it'll cover everything.

Hope this helps.
saxon
  

RE: Seamless versus seamed tubing

The ASME code section II lists the different fabrication spec requirements between seamless vs welded and the small print notes define the circumstances and limitations of each type.

Each vendor of each type of equipment has his own guidelines as to when they would risk using welded tubes. Generally mfrs have a 1 yr warrantly ,and will not use welded tubes if there is a risk of failure in the first year. From a user standpoint, the long term availability and the realtime cost of an outage due to a tube failure vs the first cost savings needs to be considered.

RE: Seamless versus seamed tubing

There is a publication from Dupont titled:

"Welded or Seamless Heat Exchanger Tubes, That is the Question" by Mike James.

This talks about the difference and the pros and cons of each.

You can get this off of thier website.

RE: Seamless versus seamed tubing

It is generally cost driven.

Seamless is generally used for small diameters.

Welded pipe such as ERW or DSAW are used for larger diameter piping.  ERW is generally cheaper but had a bad reputation in the past.  Most senior metallurgist think that DSAW is better.

RE: Seamless versus seamed tubing

Seamless tubing is generally considered superior in terms of corrosion resistance, mechanical properties and smoother interior surface.  The latter factor is especially important where high purity is involved, as in semiconductor and pharmaceutical industries (where electropolished tubing and fittings are commonly supplied, see for example http://www.valex.com/html/2_con.asp?page=specs) or in high-end heat exchangers, to reduce deposition.  

Re the paper "WELDED OR SEAMLESS HEAT EXCHANGER TUBES, THAT IS THE QUESTION" mentioned by hiliter (which I couldn’t find at Du Pont, but is available at 2 Avesta sites:
http://www.ast.avestasheffield.com/tech_support/docs/ast_techpaper_welded_or_seamless.pdf or http://www.asttube.com/template/Page____4683.asp):  It’s a very worthwhile read, and I agree that it is possible to cold-work and heat-treat welded pipe/tubing up to the level of seamless, and further, that one might conceivably get a bad batch of seamless.  But, money talks.  Enough specifiers are willing to pay a premium for seamless that it is widely used and available.  And of course, seamless SS is available that meets both ASTM A213 and A269 whereas welded can only meet A269.

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