There are different quality grades on hot dipped galvanizing. Those quality
grades are basically the size of the zinc layer.
For hard enviroment areas, galvanizing is thicker.
For extra protection, a special paint coat is needed, on the top of the hot dip
galvanizing.
It is two or three layers of two-componenets paint, called aliphatic enamel.
So, if you hot dip galvanize a tower, with thick zinc layer, industrial grade,
then you apply two or three layer of aliphatic enamel paint, you will get top
professional protection, lasting many years.
73, Maximo EA1DDO
________________________________
De: TowerTalk <towertalk-bounces@contesting.com> en nombre de Richard Smith
<n6kt1@sbcglobal.net>
Enviado: lunes, 9 de agosto de 2021 2:51
Para: 'towertalk@contesting.com' <towertalk@contesting.com>
Asunto: Re: [TowerTalk] Experience with Sacrificial Zinc?
Hi Grant,
Thanks for your response. At our station in PJ4, the Hot Dipped Galvanizing is
holding up well, but some parts are Electro-Galvanized and are already
corroding. Part of the problem is erosion from trade winds, which seems to wear
down the Electro-Galvanizing, which then exposes the base metal to a corrosive
environment. Specifically, the Orion rotor drive plates and mast clamps seem
susceptible to the erosion and the subsequent corrosion.
I was wondering if attaching a piece of zinc metal directly to those specific
parts would slow down the corrosion. The team is looking at changes to help
this situation in the future, but I'm also trying to find a quicker solution
for the parts that are already installed.
The black tar coating followed by PVC tape sounds like a very good solution for
buried parts.
73, Rich, N6KT
On Sunday, August 8, 2021, 05:11:51 PM PDT, Grant Saviers
<grants2@pacbell.net> wrote:
The MIL-HDBK-419A talks a little about this topic. Adding Zn electrodes
to a galvanized tower creates a parallel circuit, not clear which will
go first IMO. Impressed voltage systems are probably a better option.
google it.
I black tar coated my galvanized guy anchor rods and then wrapped them
with 20mil 2" wide PVC tape for abrasion resistance to 2 feet above
grade, same as done for black iron gas pipes that are buried. Should
last longer than me.
Grant KZ1W
On 8/8/2021 16:30, Richard Smith wrote:
> Hi Tower Talkers,
> It seems that sacrificial zinc is commonly used in boating to stop corrosion.
> The sacrificial zinc corrodes and "saves" the metal to which it is attached.
> Does anyone in TowerTalk land have experience with using sacrificial zinc
> with towers and/or antennas?
> 73, Rich, N6KT
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|