Erosional Velocity in Nozzels

[mmairaja]

I have to calculate erosional velocity through an inlet nozzel of a flare knock out drum. I am not sure if it has to be calculated the same way as we calculate for the pipelines. Can someone give me some tips/ or reference where i can find the related information.
thanks

 

[codeeng]

Why would you think the nozzle would be any different to the pipeline, erosion wise?

 

[vesselguy]

Just put on a wear plate at the opposit end of the nozzle. Since a FKO drum is PWHT then put on a jig so the wear plate can be removable if required.

 

[mmairaja]

Thanks for your replies, i dont think that its different from the pipeline,I calculated it according to API RP 14E. but someone senior told me that it will be different, thats why i was not sure.I couldn't find it in ASME VIII or B31.3. I found research papers " Erosion in Elbows in HC Production" (

http://www.hse.gov.uk/research/rrpdf/rr115.pdf)

and "An Alternative to API 14E Erosional Velocity Limits for Sand-Laden Fluids" by Mamdough M Salama.They were found to be very helpful.
--
Mairaj

 

[MJCronin]

mmairaja,

The TEMA code (for shell-and-tube heat exchangers)has limitations on fluid momentum which affects nozzle sizes. When the momentum criteria is exceeded, TEMA requires impingement plates on tube bundles.

You typically end up with a limit of 3-5 ft/second for the fluid.

Although this does not specifically apply to your vessel, it is reasonable to argue that if you conditions meet the TEMA criteria, they should be acceptable for your case.


My opinion only ..

-MJC