huangyhg

galvanizing bar joists
anyone ever galvanize a bar joist? is it possible? particularly the lh series? span is roughly 70 feet, so it may not even fit in the tank, let alone be able to be shipped as a 70 foot piece.
there are tanks that big. it depends on where you are located. valmont (steel pole supplier), i believe, has tanks that big and they galvanize for steel suppliers as well. as far as shipping, 70' long would require special permit.
call smi joists. i believe it was someone from smi who told me several years ago that they tried to hot dip some of their joists. although the joists were not damaged during the hot dip process the galvanizing could not get to all of the nooks and crannys between the chords.
the joist supplier will determine who they will send the joists to for galvanizing and the size of their tank will determine how many splices are required in the joists. we did some 120 footers and they were fabricated in 3 pieces.
jike, i'm a little surprised at your experience. i went to a steel joist institute seminar late last year where one of the presenters talked about hot dip galvanizing and was very discouraging. he seemed to imply that the heat of galvanizing warped and distorted the joists.
by the way, lppe, the american galvanizer's association has a website (
we did not have any problems with distortion or warping. perhaps, because these were lh or dlh joists. i would think with small chords or webs, there might be those kind of distortion problems.
lppe,
i used to work at a steel fabricator, and everything you are wanting to do, they have done. just make sure you call out what to touch up the field welds with. there were some cold galvanizing agents that significantly outperformed the others. i'm sorry, i can't remember who the manufacturers were.
fyi, little known fact....you can also get steel sections in 70' lengths. might take a bit longer because you have to wait for rolling, but it can be done.
chip

__________________
借用达朗贝尔的名言：前进吧，你会得到信心!
[url="http://www.dimcax.com"]几何尺寸与公差标准[/url]