Pump Station Steel Piping Header - interior corrosion concerns
Pump Station Steel Piping Header - interior corrosion concerns
(OP)
We are currently working on rehabilitation of a wastewater pumping station by placing 30 years olds pumps and other upgrades. Existing 24" steel piping header, also 30 years old, has a current wall thickness of over 1/2". We would prefer to leave the header and not replace it due to operation shutdown timeframes and overall additional costs but not sure if it would last another 20-30 years if not replaced. We are not sure if the original steel header had any interior lining or just bare steel. Anyone familiar with this or have any recommendation or information on this issue - THANKS!!
Jim
Jim





RE: Pump Station Steel Piping Header - interior corrosion concerns
Why don't you just compare the as installed pipe thickness to the existing pipe thickness?
RE: Pump Station Steel Piping Header - interior corrosion concerns
RE: Pump Station Steel Piping Header - interior corrosion concerns
BigInch
-born in the trenches.
http://virtualpipeline.spaces.msn.com
RE: Pump Station Steel Piping Header - interior corrosion concerns
RE: Pump Station Steel Piping Header - interior corrosion concerns
It seems near incredulous to me that a water/wastewater header with steel pipe was installed on or about 1976 with no lining whatsoever (do you by any chance have any way to drain and are there any hatches, blind flanges, air releases, spools etc. that could be quickly removed in a short dowen period to sneak a peek at the interior conditions?); however/regardless, if you have confirmed a consistent steel thickness of 1/2" now in this 24" steel piping after 30 years of service, I'm not sure (even if this is bare piping) that I can come up with a persuasive reason you would not be able to get a few more good years out of same in your rather low pressure/40 psi service!
I believe it has however been some common to line water and domestic wastewater pipes that flow full (and non-acid-producing etc.), for internal corrosion protection and maintenance of flow properties, with cement mortar. It is my understanding this can even be done to steel and other piping in place, e.g. in accordance with ANSI/AWWA standard C602,CEMENT–MORTAR LINING OF WATER PIPELINES IN PLACE— 4 IN. (100 mm) AND LARGER, although I am not sure how practical such operations might be for your operational/waste water header configuration/situation. If you are interested in this you might do a search for experienced in-situ lining contractors in your area, that might help with further evaluation/remediation of any problems.
RE: Pump Station Steel Piping Header - interior corrosion concerns
RE: Pump Station Steel Piping Header - interior corrosion concerns
BigInch
-born in the trenches.
http://virtualpipeline.spaces.msn.com
RE: Pump Station Steel Piping Header - interior corrosion concerns
Consider the question "What wall thickness would you use as a replacement 24" pipe header?"
The "Standard" wall thickness of 24" pipe is 0.375 inches (Schedule 20), even "Extra Heavy" has a wall thickness of 0.500 inches. Since the existing pipe has a 0.5 inch wall thickness, then replacement with much heavier (Schedule 40, or greater) pipe would be required to make any sense. In light of the low pressure, etc. using a pipe with that much "safety factor" seems, IMHO, to be unwarranted - and this is even if a corrosion factor is included.
A couple of pages for references for my "numbers"
http://www.steeltubeinstitute.org/pipe.htm
and
http:/
www.SlideRuleEra.net
RE: Pump Station Steel Piping Header - interior corrosion concerns
RE: Pump Station Steel Piping Header - interior corrosion concerns
Richard A. Cornelius, P.E.
WWW.amlinereast.com
RE: Pump Station Steel Piping Header - interior corrosion concerns
RE: Pump Station Steel Piping Header - interior corrosion concerns
"We do not have any original pipe design or pipe information."
Most piping that I have seen is marked in some manner. You might want to closely examine the piping. Surely, you must have the original design data as well.
Once you have determined what type of pipe that you actually have, compare the thickness of the original pipe to the corrosion over the the 30 years. That should provide you with an answer.
RE: Pump Station Steel Piping Header - interior corrosion concerns
Richard A. Cornelius, P.E.
WWW.amlinereast.com
RE: Pump Station Steel Piping Header - interior corrosion concerns