SA-194 allowed starting materials

[QAFitz]

In the "Chemical Composition" section of SA-194 a paragraph stating that a starting material with elements outside of those listed in the tables cannot be used. This precludes the use of an alloy steel (41xx) as a starting material for any of the carbon steel SA-194 grades (SA-194 Grade 2, or 2H etc.) or a XM-7 starting material for a SA-194 Grade 8 nut. I see that paragraph is in the 1989 SA-194 version but not in the 1980 SA-194 version. So I can bracket it but cannot pinpoint it. When did this paragraph (requirement) first appear in SA-194 ? Bonus question: When did it first appear in the ASTM version of A-194 ?

 

[metengr]

The 2001 Edition of SA-194 Specification does not contain such a statement.

I also have a copy of the 1984 edition of ASTM A-194 Specification, and no such statement appears.

 

[QAFitz]

metengr,
The paragraph I'm looking at is 6.5 and in this instance I'm in the 1998 SA-194 spec.
You may be correct in that the same paragraph may not be in the year you arelooking at, however, please check out the common requirements as noted in ASTM A962, which I believe is one of the reference documents in the ASME Standard. The paragraph in A962 is 7.6 in the 2003 ASTM Standard.

 

[metengr]

Yes, I see the statement. The paragraph you refer to applies to scrap material that could be used to develop a heat of material. My understanding of paragraph 6.5 is that scrap used to produce a heat cannot have any alloy elements beyond those mentioned in Table 1.

 

[QAFitz]

metengr,
Very interesting view, I've not heard it expressed this way. As you view it then, I could use AISI 4140 or even 4340 to make a 2H nut. I was under the impression that paragraph was added to eliminate just that: using an alloy steel to meet a carbon steel (cost cannot be used as a rational argument).
I seem to remember people selling 2H nuts with charpy results that met not only ft.lbs but also 25-MLE. A feat only possible if the stars were aligned correctly and the alloying elements were present in sufficient quantities.