Internal Pipe Lining

[MTEE1732]

Looking for options for replacement of carbon steel flare piping system with internal corrosion that has thinned line to close to retirement thickness. Design pressure is 30 PSIG but design temperature is 600F and length is about 700ft and diameter is 36" with several branches. Has anyone used an internal lining system that can handle these kinds of temperatures. Liner would be exposed to heavy hydrocarbons, LPGs and sour gas.

 

[MikeHalloran]

I understand how the pipe near the actual flare can be hot, but what about the rest of it? How hot is the highest temp gas flow entering the pipe?



Mike Halloran
Pembroke Pines, FL, USA

 

[LittleInch]

At tthat sort of temperature (315C in my language..) it takes out all the normal paint and plastic liner systems or non metallic piping i am aware of (there may be special spray applied ) so leaves you with either Stainless steel (should be pretty thin at a DP of 2 bar) or some sort of internal CRA cladding. The problem is your multiple branches and their connections, which is why for 200 odd metres stainless sounds like a good base option to me to work from as regards other options (cost, construction, long term integrity etc).

Alternatively have you thought about shelling around the existing pipe on the outside to extend it's life, either fibre glass, steel half shells with epoxy grount or steel strip? Your weight would increase and so solving one issue creates several more, but depends on whether your internal corrosion is localised or wide spread and wheter you have a turnaround planned to actually install a new flare header. This would still require replacement once you've eaten throgh your original header material, but is an alternative combined with regualar UT inspection.

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