Sorry I hit submit too quickly then. I am also thinking of usng carbon steel painted or stainless for the above ground pipework. Would it be stupid to go for Carbon? What elements of the water treaztment should I look for to ensure carbon steel will be ok?
And yes I know of problems, especially in service water or feedwater systems. Doesn't mean that carbon steel isn't used though. It just argues for a good erosion/corrosion program (at least if you're in the nuclear industry and such things are justifiable.)
Patricia Lougheed
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Yes its cement sprayed on the outside of the pipe it comes in really long lengths, welded together and cement sprayed on the weld. I was just wondering about the internal corrosion.
it is usually cement mortar lined on the inside. this is the most commonly specified type of lining for steel and ductile iron pipes. for highly corrosive water you might also need cathodic protection
According to US Army Corps of Engineers, for cooling water pipe less than 80 mm, use seamless Copper tubing type K, solder joint ASTM B88M. For 80 mm and larger, use seamless Black Steel, ASTM A53.
In my experience, for Black Steel pipe A53 larger than 80 mm, if exposed use standard schedule (schedule 40) and if embedded use extra heavy schedule (schedule 80).
I am working with Saudi Aramco Total Refinery. Here in my project, we use Carbon Steel Pipes for Cooling water service. Following are the cases in Cooling water normally Saudi Aramco follows :
1. Underground Service : RTR Pipes
2. Large bore above ground : Carbon Steel Pipes
3. Small Bore above ground : Carbol Steel piping with internal fusion bonded epoxy coating.
Yes for sure, there is a problem of corrosion. Usually corrosion inhibitors will be added for Cooling water services. Choice of selecting a higher schedule piping is also advisable.
