Wednesday, April 1, 2009

Re: CHINESE STEEL

I was involved with a similar situation using Korean steel. We were
given the main section parameters (Ix, Sx, Zx, etc) . We weren't given
J and Cw so we had to use the conservative equation for calculating Lr
for calculating the moment capacity under lateral-torsional buckling.
When we were mostly done, we found out that the promised steel strength
of 50 ksi was actually 46 ksi. The other item I remember that there
wasn't the wide suite of sections that you get in North America.

Gary L. Hodgson and Assoc. wrote:
> Bill,
> One of my customers insisted on buying Chinese steel so I had to use
> it. The yield strength is only 34 ksi (for the steel he was using) so
> the savings may not be as good as it looks to the guy just buying on
> price alone. Their W shapes are not the same as North American
> shapes (or European also) so you can't compare them on price per pound
> basis either. The publications (that were given to me) on their steel
> are not as informative as ours, i.e. no J, Z, Cw, just area, mom of
> inertia, section modulus, depth, width and thicknesses.
>
> Personally, I wouldn't buy any of their stuff based on personal
> experience - too many junky products. Back in the 70's, Hodgson
> Custom Rolling (my brother's company) had a big job rolling a lot of W
> shapes. Every so often one these beams would snap and you could hear
> it in the office 75 ft away. The steel came from Canada, the USA,
> Japan and occasionally Europe - no Chinese steel then. The fewest
> number of breakages were Canadian, then American, then European and
> Japanese. I am sure everybody has improved their steel since then,
> but I suspect that the Chinese steel today would be at end of the
> list. And Canada has stopped making wide flanges.
> Hope this is helpful.
> Gary
>
> bill@polhemus.cc wrote:
>>
>> We've got an overseas job (so "Buy American" isn't an issue) where
>> they're contemplating using structural steel from the Peoples'
>> Republic of China.
>>
>> I'd like to know if anyone has any direct or indirect experience with
>> use of Chinese-made steel. And please, I'm not looking for hearsay
>> (heck, I could contribute that myself), but actual anecdotal evidence
>> of problems (or sucesses) with its use. Specific details would be a
>> plus.
>>
>> I know that a lot of foreign-made steel was problematic in the past,
>> and I also know that the PRC hasn't got the best rep regarding
>> quality control for a wide range of manufactured goods in the very
>> recent past.
>>
>> But what I'm looking for is solid information.
>>
>> Thanks in advance.
>>
>
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