NACE compliance for non-pressure retaining parts of a vessel
NACE compliance for non-pressure retaining parts of a vessel
(OP)
Hi all.....
Do we really need to check the NACE compliance(MR 0175/ ISO 15156) for non-pressure retaining parts of a vessel operating in sour service?
Because for the non-pressure retaining parts, we will not get partial pressure of H2S. So only having the temperature and chloride concentration, how can we check the compliance....
thanks in advance
regards,
Nandhini
Do we really need to check the NACE compliance(MR 0175/ ISO 15156) for non-pressure retaining parts of a vessel operating in sour service?
Because for the non-pressure retaining parts, we will not get partial pressure of H2S. So only having the temperature and chloride concentration, how can we check the compliance....
thanks in advance
regards,
Nandhini





RE: NACE compliance for non-pressure retaining parts of a vessel
You state that the pressure vessel is operating in sour service. This implies that the fluid contains H2S. Is this a heat exchanger or something similar, with sour fluid on one side and chloride-containing water on the other?
RE: NACE compliance for non-pressure retaining parts of a vessel
It is a Separator vessel and made up of Carbon steel with 6mm corrosion allowance with an internal epoxy novalac ceramic lining.
Process conditions are
Operating temp of vessel = 90 deg.C
Operating Pressure of vessel = 174 psi
Chloride content = 149549 ppm
H2S mol% = 0.31
Removal internals (weir plate, demister, etc.) of this vessel are in 316L Stainless steel.As per NACE MR0175- Table A.2, it is not acceptable at this process conditions.
My query here is, for removable internals i.e. for non- pressure retaining parts which is in equilibrium pressure, can we check NACE compliance ......? Because the standard is silent regarding this.
RE: NACE compliance for non-pressure retaining parts of a vessel