Dear all engineers, I have a pro

[patchlam]

Dear all engineers,

I have a project where the corrosion allowance is not stated by client or any standard. Basically I need to use the carbon steel pipe to transfer the thermal oil inside a heat exchanger. The temperature can go as high as 410 degC and the pressure at 20 barg. May I know if that any way I can specify the corrosion allowance for this case so that I can calculate the minimum required thickness? Thanks!

 

[SJones]

What corrosion rate are you expecting for carbon steel when exposed to the thermal oil?

Steve Jones
Corrosion Management Consultant

http://www.linkedin.com/pub/8/83b/b04

All answers are personal opinions only and are in no way connected with any employer.

 

[EdStainless]

If the oil is clean then the corrosion rate will be zero, and you won't need any corrosion allowance.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

 

[patchlam]

Hi, I am not sure about the corrosion rate that I should set, but I can say that the thermal oil I am trying to use is Therminol synthetic heating fluid. And the design life of the piping is about 22 years. Maybe they will help us to indicate what kind of corrosion allowance I should apply in my thickness calculation?

 

[pdp123]

Generally the minimum Corrosion Allowance depends on the Project Specification.
For CS Piping even the Fluid is water one has to take a certain minimum value.

PME

Hard Work with Smartness is the key to success

 

[georgeverghese]

Standard practice is to use 1.0mm CA for nominally non corrosive service. But you have to keep an eye on this Therminol fluid for pH during plant operation, and also design for and keep a N2 blanket on the expansion drum, else corrosion rates will be higher.