corrosion protection buried carbon steel pipe

[rikkim]

I am looking for help in protecting a 6' carbon steel
buried pipe against soil contamination, alkalinity,
acidity... whatever may be a problem. Would a bituminous
coating, galvanized and then an epoxy coating, or
some other sacridicial or cathodic protection be best?

 

[rustbuster1]

The temperature of the pipe has to be known before you can get any recommendations. Why does the pipe have to be carbon steel? Perhaps because it is hot? If not, it is not such a good idea to overlook HDPE or FRP and maybe even stainless steel at todays prices (low) if metal is required.

 

[Rich2001]

go to this site

http://www.pdhonline.org/

click on course S110

download chapter 8 and look at the other info. This has charts that you can use to determine life using various coatings.

 

The only positive answer I can give you without asking a lot of questions is, do not use Galvanized metal underground. While Galvanizing is great for atmospheric type protection, it is not meant for use underground and/or submerged under water.

 

[PAN]

I always find the buried carbon steel pipe with wrapping tape for external corrosion protection. I will appreciated if anyone can compare this method with cathodic protection....Thanks for your comment.

 

[metalsrus]

Are you putting 6 foot diamter carbon steel pipe in the ground or just 6 feet long smaller dia. pipe? otherwise...

Helps to know service temperature and chemical service inside of pipe first. Certain laws need to be complied with if this pipe is used to transport hazardous fluids beyond the boundary of your immediate facility on to/across public lands or if the pipeline is near a waterway. Save yourself the future liability.

Assuming your pipe is under 100 F most tape wrap works. A bituminous coating/tape can be very good. Hardly anything can coat over a bituminous coating/tape. Really don't need anything.

Cathodic protection designed by a properly educated and certified individual using impressed current or buried anodes will solve your problem if it is not too unusual.

A pipe inside a pipe is a good practice if this is a short section. You have built in leak detection ability.

Happy Engineering

Buried stainless steel can have its own problem if you are near high salinity water or other industrial contaminates.

 

[BarryMartin]

Usually a combination of coating and cathodic protection will provide the best economics. The coating reduces the area to be protected by the cathodic protection system reducing its cost. The cathodic protection system provides a protection system that will protect any uncoated areas that occur during production or installation.