Minimum Thickness for ASTM A36 Sheet...

[cozdemir]

I have a quick one, although not easy to find the answer documented anywhere. What is the minimum thickness one can order A36 Steel sheet? I am doing a calc and the designer specified 1/8" A36 sheet, but the customer is now saying that A36 does not come in a thickness less than 3/16". Is this true?

Basically, I am looking for some documentation somewhere telling me (so that I can show them) that A36 does come in a 1/8" thickness. Thanks!

 

[Metalguy]

Apparently you don't have the ASTM A-36 standard handy. Well, neither do I until tomorrow. But that's where you'll find the answer.

 

[cozdemir]

No, I do have the standard and it does not specify a minimum. What it does say is this. Under Table 2 Chemical Requirements, there are thicknesses designated according shape. For plates, the bottom range says: To 3/4" [20] incl. Basically, its saying up to 3/4" or 20 mm, but no bottom limit. I can only assume that 1/8" is included in the range, but that's an unverified assumption requiring verification at some point!

thanks

 

[IFRs]

I think 1/8" is below the thickness of "plate" and falls into the "sheet" category. As such, A-36 may not apply, and if I were you I would look for a similar specification that covers "sheet".

 

[cozdemir]

Well, A36 is a spec for Carbon Structural Steel, period. Now, we are considering substituting A570 grade 45 so that the mechanical properties are enveloped with our calc, but we want to make sure that we absolutely have to before we do that. Also, we want to make sure these guys are not telling us something that is, in fact, incorrect. Therefore, we just want to make sure so that we are covered. Its a CYA thing paralleled with the principle that A36 should be fine. Thanks again.

 

[TVP]

cozdemir,

As IFR stated, 1/8" thickness falls under the category of sheet/strip, and therefore ASTM A 570 should be referenced instead of ASTM A 36. ASTM A 570 is listed as an Appurtenant Material Specification in Table 1 of Section 4.

 

[CWIC]

I have the current copies of the ASTM A 6 and A 36 standards. Neither of these delineate the cut-off point for plate to sheet (or vice versa).

As previously noted, plate is generally considered to be material >1/8" in thickness.

 

[ornerynorsk]

Plate is classified as anything 3/16 and thicker. Sheet is 7 gage and thinner. A569 is the closest thing to A36 plate, both are bottom-of-the-barrel, merchant quality steel.