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RE: Wall thickness of HSS sections

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Paul:

I agree that the ASTM standards should have been updated more
regularly to reflect changes in manufacturing tolerances.  However, I
insist that the fault is with the tube producers.

Although the ASTM standards (A500, for instance) may be too loose, the
intent of nominal thickness plus or minus a tolerance (10 percent) is
clear.  That's why I carefully chose the descriptors "unethical,
unprofessional, legalistic, [and] cheap" for producers who
intentionally violated the intent of the standard.  Such producers
have a tighter tolerance in their production than that allowed by the
standard, which is good.  However, they have targeted a wall thickness
that is substantially less than nominal.  This is the result of a
conscious effort to cheat the intention of the standard.  What they
did is not illegal--it is cheap (which according to MS Word is
"comtemptible, base, trashy, cheesy, and miserly").

It is this focus on what is "legal" rather than what is "right" that I
find personally and professionally disgusting.  Of course, this
misplaced focus in our society is not unique to steel producers.

-Mike


-----Original Message-----
From: Paul Ransom [mailto:ad026(--nospam--at)hwcn.org]
Sent: Saturday, June 24, 2000 5:44 PM
To: seaint(--nospam--at)seaint.org
Subject: Re: Wall thickness of HSS sections


> From: "Mike Valley" <mtv(--nospam--at)skilling.com>

> b/t is a little high).  Instead, I am more irritated by the
reduction
> of overall section properties forced on us by unethical,
> unprofessional, legalistic, cheap, low-life steel producers; I am
> personally and professionally disgusted by the level of chiseling
> encountered in our system.  I believe that the correct solution is
to
> fix the material specs so that we get what we pay for, instead of
> moving to a system of "nominal" dimensions.  Of course, what is
right
> doesn't usually happen.

Mike,
The fault is in the ASTM standards for tube sections. It's the same
with
gage materials. The standards were established to reflect
manufacturing
capabilities at the time. ASTM was reluctant to change the standard.
Now, we have new standards to reflect the current manufacturing
practices. In Canada, we have been reducing capacity of A500/A53 tube
sections by as much as 20%, for several years, when we were unable to
obtain HSS.

--
Paul Ransom, P. Eng.
Civil/Structural/Project/International
Burlington, Ontario, Canada
<mailto:ad026(--nospam--at)hwcn.org> <http://www.hwcn.org/~ad026/civil.html>