NACE MR 0103 - Material

In what context?

As far as acceptability is concerned, the local standard applicable to the project will determine this. What is the standard?

it is required for FLARE STACK.

in project standard for carbon steel carbon contain shall be less than 0.23% and carbon eq. will be 0.43%.

In NACE MR-0103 code carbon contain shown as less than 2% but i have never seen that much qty. of carbon in materials like 516 gr.70

Then it would be compliant, self-evidently.

If the material specification includes MR-0103, then nothing "instead of NACE MR-0103" is compliant.

From slabs, for T between .3125 to 1.5"(plate)

C is .18 to .22

From slabs, for T up to 3.00"(plate)

C is .23 to .27

where it is exactly stated.

Maybe the answer lies in NACE literature such as this:

http://www.nace.org/cstm/Store/Product.aspx?id=6e58e286-6132-4753-82d3-632d5e178892

NACE Store - MR0103-2012, Materials Resistant to Sulfide Stress Cracking in Corrosive Petroleum Refining Environments

There are several major differences between MR0103 and MR0175/ISO 15156:

_ The refinery standard guidelines for determining whether an environment is "sour" are

quite different from the sour environment definitions provided in previous and current

versions of MR0175

.

_ The refinery standard does not include environmental restrictions on materials.

_ Materials and/or material conditions are included in MR0103 that are not listed in

MR0175/ISO 15156.

_ Materials and/or material conditions are included in previous and/or current versions of

MR0175/ISO 15156 that are not listed in MR0103.

.

_ Because welding is prevalent in refinery piping and equipment, MR0103 places extra

emphasis on welding controls in several material groups, most notably the carbon steels.

Applicability of MR0103. Both MR0175 and MR0103 include sections that describe applicability

of each of the standards. Both describe material factors and environmental factors, and provide

guidelines to the user on how the standard should be applied. Note that both standards require

the user to specify whether the environmental conditions are such that the material requirements

of the standard should be applied.

One of the key differences between the MR0175 and MR0103 standards lies in the the environmental conditions under which SSC is likely to occur. MR0103 covers a

broader range of sour environment conditions experienced in downstream process units. These

are based on:

_ User's plant experience and practices

_ Existing NACE and industry recommended practices and reports (i.e., NACE RP0296,3

8X194,4 8X294,5 API Publication 5816)

_ A fundamental understanding of atomic hydrogen generation in the sour service corrosion

reaction and the subsequent rate of hydrogen flux into the process-contacted steel, i.e.,

combined effects of pH, H2S and HCN.