Wait a bit, I didn't notice there were other posts. Let me read them all first.
HM
Wait a bit, I didn't notice there were other posts. Let me read them all first.
HM
That's OK, I had the wrong message sort.
HM.
Yes.
Ned Simmons
I was a bit astonished too. My books says something of 0.675...0.715E5 for Al. And I don't have a table showing something like 6061. Don't know.
Yea, the abbrevs are the German ones. And I _really_ don't know how you translate them. :-)) S for section modulus. That sounds very right to me.
Thanks for checking!
Nick
Yes, and then I saw that I forgot to note that it is for Al, and postet the clarification some minutes later.
Exactly.
No, it is a constant, depending from the material. For steel, it is
2.1E5.
OK :-)
What square of the length? I have never written that. N / mm^2 is the unit, not a formula. For every symbol I used, I gave the units. If you do the math just with the units, you can check the result a bit. N is a unit (Newton, force) and I described it to. I didn't use N as a symbol. It's also quite confusing to use the units in a formula. So I didn't, except for the result.
I always use the same pattern: Write the formula and then, with the same sequence put in the numbers. No shortcuts, no numbers that aren't derived from a formula. Your last statement is wrong.
Nick
OK. I messed it al. All is clear now.
Let me follow through the other matters, I will come back.
Thank you Nick. Henrique
If you're an Iraqi, and are ordering it in quantities in the tens of thousands, then the price is about $15 for an 81mm tube 900mm long, with
3.1mm wall thickness and 0.1mm wall thickness tolerance, and in the -T6 heat treatment state.That includes the special fee for busting sanctions on nuclear-related materials.
About $3.60/lb. - pretty good price. Almost exactly Yarde's price for drops of 7075 solid rounds.
Ned Simmons
They shopped it around for quotes. :-)
These were, of course, the infamous aluminum tubes whose interception on their way to Iraq was used as part of the justification for war. The supposedly extraordinarily-tight tolerances were:
Outer diameter: 81.0 +0 / -0.1 mm Inner diameter: 74.4 +0.1 / -0 mm
Somehow those numbers never seemed to make it into press reports -- not even after the war. I had to dig them out of the Duelfer report (where they're in volume 2, second section, in page 27 of that section, which is page 164 of the pdf file).
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