ASTM A36 vs ASTM A529 Grade 50

[ray83]

Can any one help me resolve this issue. Our vender supplied us U-Bolts which he maufactured (bending and thread cutting)from a 1-1/8" steel rod purchased from a supplier. The ASTM for this material shown on the MTR is ASTM 529 grade 50, where as the project specification requires it to be ASTM A307 grade c, ASTM A36 or ASTM F1554, grade 36.
The structural engineer rejected stating that this did not meet the requirements, i see this exceeding the requirements with a grewater tensile strenght. what are the orther factors need to be looked into to ensure it meet and exceeds ASTM A36. Also need to know if this material can be galvanized.

Appricaite your help.

 

[HgTX]

You need to look at those specs and see what all the requirements are. It only needs to meet one of them.

Hg

Eng-Tips policies: faq731-376

 

[Ron]

Possibly the reason for rejection is the potential difference in ductility of the two materials. The specification is for a mild steel with good ductility. The supplied steel has higher strength but lower extensibility (ductility) and thus might be a reason for the rejection. Ask the structural engineer of record for clarification on the rejection.

 

[stanweld]

Another reason is that the Engineering Specifications do not reflect 21st Century metallurgy and design philosophy. A-36 forever!!!

 

[QAFitz]

If the certification had not referenced any ASTM or other Standard, would the engineer have rejected the parts/paperwork?
If the vendor has reconciled the Chemistry and Strength properties and they align with the ASTM Standards you allow, I would be hard-pressed to accept the engineers rejection.

 

[BigH]

I get a lot of this on my projects - A36, JIS 4106 SMYA, etc. with a need to try to figure out equivalents. The way I have looked at it, say for deformed steel rebar, the steel doesn't "know" what spec it is supposed to meet. So, look at the mill certificates for your project's requirements, say ASTM A615 and compare the mill cert to it - for mechanical, chemical and physical properties. If it passes, it is good even thought the steel might have been made to Thai SD40. Many times I have found that the specification is designed based on strength - the designers might not have the foggiest idea of the minutiae of the chemical properties.