Smart questions
Smart answers
Smart people
Join Eng-Tips Forums
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Member Login




Remember Me
Forgot Password?
Join Us!

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips now!
  • 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!

Join Eng-Tips
*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.
Jobs from Indeed

Link To This Forum!

Partner Button
Add Stickiness To Your Site By Linking To This Professionally Managed Technical Forum.
Just copy and paste the
code below into your site.

lilrascal (Civil/Environmental) (OP)
20 May 09 10:34
I have a project that I've been asked to help on involving a waste water pump station (not my forte).  The contractor has submitted Cast-in-place Galvanized Steel Pipe Sleeves. The project specs read only that the sleeves should be made of or coated in a corrosion resistant material. I'm bothered by the possibel affect of Hydrogen sulfide gas on the Galvanization. I'd prefer HDPE or Coated DIP. Please comment and TIA.
bimr (Civil/Environmental)
20 May 09 13:08
Where are these sleeves used?

Embedded into a concrete wall in a wetwell?

Diameter of the sleveve.

Municipal wastewater?


 
lilrascal (Civil/Environmental) (OP)
20 May 09 13:12
The sleeves penetrate the concrete wet well for the influent and effluent piping. It is a regional waste water pump station with residential, commercial ,and indusrial flows. Sleeves are for 10", 12" and 24" pipes.
cvg (Civil/Environmental)
20 May 09 13:35
I think you could make a case that galvanized steel is not very corrosion resistant against hydrogen sulfide (sulfuric acid). It does not meet the requirements of the spec. Plastic, epoxy, fiberglass, rubber or stainless materials and coatings might be better suited.
jgailla (Geotechnical)
20 May 09 16:59
We usually spec SS 318 for piping in wetwells.
I also agree that galvanized steel should not be used.  Lined ductile iron should be acceptable as a cheaper alternative to SS 318 if the spec is unclear.
bimr (Civil/Environmental)
21 May 09 13:56

The amount of hydrogen sulfide will depend on the climate and the wastewater characteristics. In the southern US, the effects of corrosion are more severe than in the north. You might check into what your client is normally using in this application.

Pipe sleeves are used when small piping passes through concrete walls. Wall pipe may be used for larger piping. Wall pipes are normally used in this application. Wall pipes are made of ductile iron pressure pipe with plain ends and integral water stop
 
Sometimes steel is used for sleeves as in this example:
"Where the cast iron suction and discharge lines pass through the station wall, they shall be reinforced with one-fourth-inch thick steel sleeves, welded inside and out, to the station walls. The space between the cast iron pipes and the steel sleeves shall be packed tight with expanding cement grout to prevent leakage."

Steel (with a coating) is also frequentyly used for construction of lift station wet wells.

You may use a coating over galvanized steel to protect the sleeves:

http://www.henry.com/fileadmin/pdf/literature/sf_sleeves_collars_fax_version.pdf

You may use also use flexible seal on the sleeve end:

http://www.fernco.com/plumbing/flexible-couplings/pipe-sleeve-seals

Not familiar with the use of plastics for wall sleeves.
cvg (Civil/Environmental)
21 May 09 14:27
BIMR
by plastic, I meant polyethylene. A piece of HDPE solid wall pipe could be used for a sleeve and would be very resistant to corrosion. I saw a photo (just yesterday) of ductile iron pipe which was used in a wet well in Florida. After just 18 months it was removed and was completely corroded through the pipe.

note that your reference above to steel sleeves refers to sleeves passing through the "station wall" - not in the wet well. I believe there is little chance of corrosion within the "station" as compared to the highly corrosive atmosphere within the "wet well".

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!

Back To Forum

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