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--- Begin Message ---
In a message dated 11/4/98 9:37:29 AM Eastern Standard Time,
hhuang(--nospam--at) writes:

<< Your first reply please.  I attached yours when I asked for the
clarification and the original file was lost.  I like to post it to the SEAOC
bulletin as form the steel authority if it is OK with you.  Thanks! >>


Like yours, my original message was lost too.  However, I'll try to capture
the essence of my comments ...

ASTM A36 is still available and is likely to be available for W-shapes for a
long time in the future, but this depends on the demand.  As long as our
customers continue to order it, we will produce it.  ASTM A36 is considered
the "base grade", in which a shape producers' price list is based.  Grade
extras are added to the base price in many cases depending on section size.
In the case of ASTM A36 and ASTM A572 Grade 50, many of the sections produced
are considered "multi-certified" because they meet both specifications.
Generally speaking, this is up to about the W24x162 section/footweight, where
the price is the same for both ASTM A36 and ASTM A572 Grade 50.  With thicker
and heavier footweight sections, there is a need for additional alloys to
provide the specified strength levels, so there may be a nominal "extra" for
these sections.  A quick look at our price list can determine which sections
are "multi-certified" and which are not.  

In addition to ASTM A36 and ASTM A572 Grade 50, the CSA 40.21 Grade 50W is
also included in the multi-certified grade for the same reason stated above,
it meets that specification too.  

In May 1998, ASTM approved the new "Enhanced ASTM A572 Grade 50" for (W-shapes
only), however, we are still awaiting ASTM to formally announce it and make
the new specification available to the public as a separate specification.  We
understand it is due out from ASTM within the next few weeks.  As an interim
step, until the grade is officially announced (we believe it will be listed as
ASTM A992) and approved by the various spec bodies, the "enhanced" grade 50
can be specified in accordance with the AISC Technical Bulletin # 3 (March 97)
which is available from the AISC web site.  This "enhanced" grade, meeting the
proposed specification, has been available within the past two years from NYS
and other major shape producers, as ASTM A572 Grade 50, because it is, in
fact, that grade but more "enhanced" (more restrictive spec criteria).  

We understand more designs must be using a single-grade (Grade 50) design
rather than using two distinct grades (Grades 36 & 50) based on an increased
demand for ASTM A572 Grade 50 and less demand for ASTM A36.  Eventually, we
may see the ASTM A36 grade disappearing for wide flange structural shapes,
however, this may take a long time to happen.  Again, in the meantime, ASTM
A36 is available by most, if not all, shape producers even though in some
cases it may be considered a multi-certified steel grade.  And once again, it
is suggested that the Enhanced ASTM A572 Grade 50 in accordance with the AISC
Technical Bulletin # 3 (March 97) be specified on projects whenever possible. 

Mike Engestrom
Technical Marketing Director
Nucor-Yamato Steel
(301) 694-3067
(301) 694-2349 FAX

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