×
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

Maximum Velocity in pipelines

Maximum Velocity in pipelines

Maximum Velocity in pipelines

(OP)
I am told that AWWA in some publication have produced a table of maximum allowable pipeline velocities for various piper diameters.  I know of no such table and I would be interested to know if anyone as come across such a table. I suspect the table is being quoted out of context.

brian

RE: Maximum Velocity in pipelines

(OP)
Thanks for the link but  I am specifically looking for a table from AWWA. Our client says it exists and requires us to comply with it but he can't give us a reference and I know of no such table. I suspect that, if such a table does exist, it is related to limiting velocities in order to limit waterhammer.

(oops for 'as' read 'has' in my first post).

Brian
 

RE: Maximum Velocity in pipelines

In the Piping Handbook by Nayyar, it lists the AWWA publications. I don't see a reference for velocity in this list, but this is the 6th edition of the Piping Handbook, and I know there is a newer version. Piping in this service isn't my area of expertise, either. I'd suggest contacting the AWWA directly. They'll either tell you what standard they have that applies, or that they don't publish one covering this issue. I suspect that they don't, since many municipal water systems have dealt with water mains that have become undersized due to increased demand, by simply jacking up the inlet water pressure to the system. The bigger pressure drop will provide more GPM, but the velocity of the water in the piping goes up with it.

RE: Maximum Velocity in pipelines

TBP  there is a recipe for disaster! But a popular one. It is estimated in the UK that 25% ofwater is lost from the pipes due to leaks. Old pipes, undersized and increased demand.... increasing the pressure sure does increase the flow but it also increases the potential for failure. Short of a major program of investment to replace everything, jacking up the pressure is an expedient that water rich environments can possibly afford in the short term.

RE: Maximum Velocity in pipelines

We do work in industrial plants that have taken that route. (We'll just add some booster pumps...) We've told them what causes the leaks in their systems (HIGH velocity), but they won't spend the money to upgrade their water lines. In some cases, we've been back to "replace the replacement" elbow (copper) in less than 6 months. The initial installation in one plant was a very cheap & nasty one done by the low bid contractor - he didn't ream any of the type 'M' copper pipe after it was cut. This is a spectacular combination - thin unreamed copper pipe combined with big velocities, in a process plant that uses water almost continuously.

RE: Maximum Velocity in pipelines

Brian,
Have you found the AWWA table or similar?

If so, please advise where.

Thanks,
Dom

RE: Maximum Velocity in pipelines

(OP)
Domenico

No - I have not found the table.

brian

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