In a message dated Fri, 9 Mar 2001 11:44:39 AM Eastern Standard Time, Vic
Rosenthal <rakefet@rakefet.com> writes:
>As a former part-time welder (not an expert) I know >that there are all kinds
>of
>heat treatment. Ice water would provide a very quick >cooling which, depending
>on the alloy, might tend to make it much too hard (and >hence brittle). Welds
>could be cracked by this process. Sometimes quenching >is done in oil to
>provide
>a slower cooling. And of course, the piece would be >very hot in the area of
>the
>weld, and less hot as you move away from it; so any >effect would be all over
>the
>map. Finally, some alloys need to be stress-relieved >after welding -- this
>usually means heating the whole part to a certain >temperature (perhaps in a
>furnace), holding it at that temperature for a >specific time period, and then
>letting it cool at a controlled rate. This is really >not the place for
>guesswork!
>Keep in mind welding destroys the galvanization in the >area of the weld.
>Things
>like tower sections are galvanized after welding by >the manufacturer. You
>will
>have to use some form of rust protection after welding.
>73,
>Vic, K2VCO
>Fresno CA
Vic,
You hit the issue on the head. It's not the welding - It's the gavlvanizing.
Let's not mention the deadly fumes given off by burning zinc.
Suppose you paint the new weld with zinc rich paint.
HOW ABOUT THE INSIDE OF THE LEG?
How will you treat the inside of the leg that you have distroyed the
galvanizing. Yea, you can forget about it and in a few years the leg may rust
out from the inside. The legs are not water tight and proper drainage is
provided and the inside of the legs are galvanized too.
So if you are going to weld only weld to the soild braces.
(ROHN welds on the tubing every day. Welding is not the issue. The welding
procedures and gavlvanizing are)
Tower2sell@aol.com
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