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Alternative coating for hot dip galvanizing for mobile communication towers in coastal areas

We are fabricators of lattice towers used in mobile communication. We are looking for a proper alternative, cost effective finish to hot dip galvanizing. Could anyone suggest an alternative method ? What is the longevity of thermoplastic coatings and that of thermoset coatings when compared to hot dip galvanizing ?

Vidyababu
Director - Bangalore, India
2007

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2007 Sir: I do not think you will find a more cost effective coating for your cell phone towers than hot dip galvanizing. If I could find a hot dip galvanized wheelbarrow, I would buy it. I am sure it would last a lifetime here on the ranch. Regards, Dr. Thomas H. Cook Galvanizing Consultant - Hot Springs, South Dakota, USA 2007 You didn't state your reason for seeking an alternative. That reason might lead strongly to some alternatives being suitable or unsuitable. For example if lifetime was your reason - wanting a longer life than galvanizing, then that will lead to some conclusions, where as is you are trying to reduce cost, then powdercoating might be a solution. Assuming its cost you want to reduce, while minimising the reduction in life expectancy.... Thermoplastic PC might be a good solution, except that to get good adhesion on hot rolled mild steel, you will probably need to shotblast it. Shotblast and plastic powdercoating in this country would be about the same cost as galvanizing. Polyester PC (thermosetting) might be good too, but again adhesion is the issue, and shotblasting the probable answer. Geoff Crowley Crithwood Ltd. Westfield, Scotland, UK

I too am seeking an alternative to hot dip galvanizing. While it is an excellent resistance to corrosion, it is also costly. In addition to the cost per pound, there are hidden costs related to masking tapped holes prior to galvanizing and then the removal of the masking hardware. When you add these two costs to the transportation costs involved, it adds up fairly quickly. We have sought an alternative but can't qualify one for several reasons one of which is that the internal surfaces of our steel weldments must also be galvanized which implies a dipping process. Any creative ideas out there?

Kenneth Deruelle
- Duluth, GA, USA
2007

An alternative to hot dip galvanized coating is ethyl silicate based zinc rich coating. This type of coating is more economical than the galvanized one and comparable in lasting or some times superior than the galvanized coating.Due to the presence of conducting binders and fine zinc particles, the ethyl silicate coating performs excellently well in coastal areas. A top coat of organic coat over it provides synergistic effects on durability of the coating.

DDN Singh
metallurgical laboratory - Jamshedpur
March 3, 2008

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Has anyone tried to compare Plastic PC v/s Galvanizing for :

life of the coated components.

Handling of the components after coating. eg. Damage to the coat while erection / transportation.

"Total cost" of the Plastic PC components v/s Galvanized comp.

Eco foot print.

Parimal Shah
- Ahmedabad
July 29, 2008