Changing from GRE to CS for Large Pipes 1

[McDermott1711]

thread378-267056

I was reading this thread and with regard to OP question:

In your opinion why the designer of PMS decided to change from GRE to CS (glass flake lined) for large sizes?

I think, at that time maybe for pipes larger than 24" the available vendor of fiberglass pipe did not have an oven large enough to cure larger-than-24"-pipes. Therefore, the choice between not-cured GRVE and CS with internal coating of glass-flake epoxy resulted in second option.

What's your opinion?

Nothing is more fairly distributed than common sense: no one thinks he needs more of it than he already has. Rene Descartes

 

[TugboatEng]

Coated steel pipe is great until it's not. Pinholes in the coating concentrate galvanic corrosion in a very small area which accelerates the formation of pits and eventually holes. There are processes to verify the integrity of the coating such as spark testing. I suggest doing this. Is it possible to use sacrificial anodes or impressed current corrosion protection?

 

[LittleInch]

More answers to a 13 year old question?

But at sizes like 66" upwards, there was probably a very small market for GRE and most would be some form of concrete pipe. Any sort of pressure rating on a pipe that big would give you enormous wall thicknesses.

The GMMR in Libya was I'm fairly sure pressurised as the pumped water from the fossil acquifers below the Sahara in 4m diam pre stressed concrete pipes.

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