Yield Strength Vs Wall Thickness/Cross-Section 2

[JHWC]

Hi All,

Does anyone knows where do I find the relevant documents based on the material yield strength and the maximum diameter it can go?

For example, yield strength of the following AISI 4130, 4140, 8630, F22, 4330 and 4340 may varies and therefore, restricting the wall thiokness.

May I ask how to Materials Engineer derive this? Any information I can look into?

Thanks,
Jeffrey

 

[mrfailure]

The yield STRENGTH does not vary by wall thickness. The yield LOAD does. Remember, Stress=Load/Area.

 

[yudhichen]

you might check Jominy test (ASTM A255) and relate how does the hardness vary from most exposed area against heat treatment to less exposed.
the rest is how each company 'confident' to mention expected wall thickness of those steel.

 

[JHWC]

Hi mrfailure,

Thanks. You made a point here. However, I think in oil and gas companies, they have this "guidelines" to determine the specified minimum yield strength (SMYS) and what is the maximum wall thickness it can go.

Hi yudhichen,

Thank you! I will read the ASTM A255 mentioned.

Jeffrey

 

[mrfailure]

What you are really looking for then are standards, and they will depend on the specific componentry. For your industry, you should look for API and ASTM specifications along with NACE 175.

 

[weldstan]

The minimum specified yield strength is defined by a Materials specification like API 5LX-60. It is then used to determine the wall thickness using Design Construction Codes like B31.4 or B31.8.

 

[JHWC]

Thanks guys.

Hi weldstan,

I just checked the API 5LX-60, it seem that it is not in use anymore.

Thanks,
Jeffrey

 

[kingnero]

EN codes (EN10025 for example) will state the minimum specified tensile and yield strength per thickness.
The thicker you buy your rolled plates, the lower the values. see the attached screenshot, this is for "regular" steel (low alloyed, low strength).

 

[weldstan]

JeffreyHo,
X60 is still in API 5L, 45th Edition, Erata 1, as either Grade L415 or X60. See Table 6.

 

[JHWC]

Thanks Kingnero, information is indeed useful!

Thanks weldstan. I will take a look.