Steel Avaliability??? 2

[SmithJ]

I work for a small steel manufacturing company. Recently, our purchasing department says that they are having a hard time finding flat bar steel in 50ksi because the mills are moving away from that and are concentrating on the lower yield 36ksi material.

I find this difficult to reconcile with my understanding that the industry was trending towards the elimination of the 36ksi material in favor of the 50ksi material (just like has been done with wide flanges).

Am I wrong in my understanding? Is it actually more cost effective for the mills to produce 36ksi plates and flat bars than 50ksi?

Also, what are your general experiences with steel availability? I am finding out that is one of the toughest parts of the job, courcing the right steel for our projects.

Thanks in advance.
JS.

 

[JAE]

Going "back" to 36ksi doesn't make sense. The trend towards 50ksi was, I believe, due to the use of recycled scrap steel which tended to create higher ksi yields and thus the new ASTM A992 specification.

 

[henri2]

I think most mill certs for ASTM A992 steel meet requirements for both A36 and A572 Gr 50. That was one of the objectives when A 992 was introduced in the 90s.

Modern Steel Construction had a great series of articles on it back in 99 (Jan-March)

http://www.aisc.org/MSCTemplate.cfm...&Template=/CustomSource/CopyrightDateList.cfm

 

[SmithJ]

Thanks for the responses.

My understanding is that A992 is available only for wide flange shapes. Is it also used to specify flat bar?

JS.

 

[JAE]

No - you are correct - A992 for WF.

 

[henri2]

After 2000 they dropped "W shapes" in the scope and replaced it with "structural steel shapes". So I guess channels and angles are in but not plates.

ASTM A992/A992M-04a
Standard Specification for Structural Steel Shapes
ASTM International

1. Scope

1.1 This specification covers rolled steel structural shapes for use in building framing or bridges, or for general structural purposes


ASTM A992/A992M-00

1. Scope

1.1 This specification covers "W" shapes (rolled wide flange shapes) intended for use in building framing.

Source:

http://www.techstreet.com/cgi-bin/detail?product_id=913394

 

[SmithJ]

So apart from A572 Gr 50, is there any other sppecification that gives 50ksi flat bar? Apparently our purchasing department is having a hard time finding A572 flat bar material.

Any ideas?
JS

 

[henri2]

ASTM A 529 Grade 50 from Nucor steel?

 

[DaveAtkins]

I only assume 50 ksi for wide flanges and WT's, because I don't know what comes in what yield stress. I do think angles typically come in 36 ksi steel.

DaveAtkins

 

[henri2]

You are right Dave, right now angles are typically A36... channels as well.

 

[SlideRuleEra]

Here is what I believe is the latest update on structural steel material specifications (Modern Steel Construction, January 2004)

http://www.aisc.org/Content/Content...onstruction3/January_2004/30725_materials.pdf

and here is the AISC Steel Shape Availability Locator for various size members

http://www.aisc.org/Template.cfm?Section=Steel_Availability

http://www.SlideRuleEra.net