×
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

Erosion Corrosion of CS Pipe in Limestone Slurry

Erosion Corrosion of CS Pipe in Limestone Slurry

Erosion Corrosion of CS Pipe in Limestone Slurry

(OP)
Does anyone know, or have reference to, the erosion corrosion rate of a straight section of CS A106 GrB pipe under a limestone slurry service?  The velocity of the slurry is 8 fps with a 44 micron limestone particle size.  I am trying to justify, or prohibit, the use of straight sections of CS pipe for this application.  The driving force for using the unprotected steel pipe is cost savings.  Of course for bends and certain straight sections (15D-20D) after bends, a basalt lined pipe will be used.

Test data would be most helpful.

Thank you.

RE: Erosion Corrosion of CS Pipe in Limestone Slurry

749kdv  Your own experiences are probably the best judge of how abrasive is the slurry,   but  there is lots of evidence that polythene pipe can greatly out perform cs with slurries. You might even find it is very ok even for the bends.
Call me if you want convincing   DW

RE: Erosion Corrosion of CS Pipe in Limestone Slurry

(OP)
Corrosionman,  Thanks for your response.  I agree with your assesment regarding the use of PP for this type application, and I have specified it in the past for underground routing.  Unfortunately, not all engineers agree with us.  This system will be run above ground and it has been determined that a basalt lined pipe would be better suited due to various construction and pipe support issues.  In order to save money, our partners are trying to skimp by stating that straight sections of the piping run need not be basalt lined.  I am tasked to provide a technical basis (by calculation) to show that although an economic analysis may prove that using unprotected steel pipe for straight sections will reduce upfront capital cost, periodic replacement of these sections due to erosion in this type of abrasive service will, in the course of a 20 year design life of the system, prove that it is NOT the best decision.  What it comes down to is the all too familar argument with the "bean counters" that spending more money initially, will save money through the years.  It is tough to collect erosion data on unprotected steel pipe ~other than bends~ and that's where my efforts have proved futile. My gut feel is that it is the wrong decision, however, without a sound technical basis to disprove their decision, I will be forced to accept it.    

RE: Erosion Corrosion of CS Pipe in Limestone Slurry

If the straight lenghts are not lined but the bends are,  do you have a step in diameter at the junctions ?   This would be disasterous.   If not,  can you get  a steel pipe whose inner dia will exactly match the inner dia of Basalt pipe ? This will lead to non standard flanges .  Do you have any branches or small dia instrument tapping points to cause problems,  and is your system at ambient temp.  Basalt has a high expansion thermal factor which will "move" the liners every temp change. Have you considered cast iron as a possible material. Is your slurry corrosive in any way.  many people confuse corrosion with erosion.  The steel gets a veneer of rust,  which is soft and easily polished off by slurry  so exposing new clean steel which easily rusts so gets polished off  and so on.   this is why very often plastics can massively outlast steel - - not stronger or tougher  just that it does not form rust. You would find rubber lining costs half what you will pay for basalt.  Cheers    DW

RE: Erosion Corrosion of CS Pipe in Limestone Slurry

Slurry Systems Handbook by Abulnaga reports Phil Venton's work on the Gladstone pipeline. Expected rates of corrosion erosion were 0.076 mm/year whereas field results were 0.25mm per year. Phil's work is reported in the BHRA proceedings.

Venton, P. B. 1982. The Gladstone Pipeline. Working paper A-4, BHRA Group, Hydrotransport 8.

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