How We Improve the Hot Dip Galvanizing Process
                     1
How We Improve 
the Hot Dip 
Galvanizing 
Process
USS UPI
2
 Recent environmental concerns have made public and private 
organizations and organs of state administration more interested in 
green technologies. In a recent study, the organizations suggested 
including hot-dip galvanizing in the list of "green" technologies. 
 The process is environmentally friendly, protects steel, and reduces 
energy requirements. In addition, it increases the capacity of a 
galvanizing plant. 
 Listed below are some of the most common improvements we've made 
to our hot-dip galvanizing process.
Reduction of Consumption of Zinc and 3
Natural Gas
In the past decade, a series of innovations have been developed for the 
Hot Dipped Galvanized process to increase the sustainability of the industry. One 
of these innovations is an improved ash solidification technique that reduces zinc 
consumption while simultaneously improving steel corrosion protection. 
To evaluate the effectiveness of the new method, process-based cost modeling was 
used to analyze the effect of different elements on coating morphology, growth 
kinetics, and structure. The leachate was analyzed and four parameters were 
measured: pH, zinc concentration, chlorides, and dissolved substances.
In batch hot-dip galvanizing, the parts are loaded onto a rack containing 50 cut-
lengths of steel. The process begins by cleaning the steel and immersing the entire 
load in a molten zinc bath. Once the steel parts are fully coated, they are removed 
from the tank and can be shipped to the job site or delivered to a paint contractor for 
application.
4
Improved Galvanization Quality
Hot-dip galvanizing protects the steel from corrosion and rusting. The service life of a 
coating of zinc is measured as the period between the first appearance of surface rust 
and the first occurrence of 5% rust. 
The thickness of the protective zinc coating determines the corrosion protection 
provided. The single most important quality check in hot-dip galvanizing is the thickness 
of the zinc coating. Besides coating thickness, other aspects of inspection include 
continuity, adhesion, and appearance.
However, the effects of hot-dip galvanizing on the mechanical properties of steel may 
not be as clear-cut. It has been shown that the yield strength and tensile strength of 
steel significantly decrease after galvanizing. 
Nevertheless, elongation A remains unchanged. The resultant change in the 
mechanical properties of steel is still an improvement in their performance. Hot-dip 
galvanizing, however, is no substitute for a thorough analysis of the metal's composition.
5
Elimination of Wastes
The ash that is generated during hot-dip galvanizing contains high levels of zinc and 
other soluble substances. This study aims to immobilize these pollutants for safer 
disposal. Three binders were selected for the solidification of the waste. 
A leaching test according to EN 12457-4 was carried out to assess the effectiveness 
of the process. Four parameters were measured in the leachate, including pH, zinc 
concentration, chlorides, and dissolved substances.
Hot-dip galvanizing involves the immersion of steel and iron products into molten 
zinc. This process is best suited for large, bulky items. It can be performed as a 
continuous process or in batches. The slag produced during this process is considered 
hazardous waste. 
In addition, the slag must be treated separately to prevent any contamination from 
other elements in the slag. The zinc slag must be stored indoors away from moisture, 
rain, or chemical corrosion.
6
Increasing the Capacity of the Plant
Improving production by enhancing the hot-dip galvanizing process is important for many 
industries. The process involves adding aluminum to the bath, which has an affinity for 
oxygen more than zinc. The aluminum forms a barrier to oxygen on the surface of the bath. 
This barrier prevents oxidation and reduces the amount of zinc ash produced. This additive 
helps increase the capacity of the hot-dip dip galvanizing process by reducing the oxidation of 
steel.
In addition to increasing capacity, it can also increase the quality of galvanized coatings. 
Steels with a silicon content of 0.04 to 0.15 percent are better suited for this process. Low-
silicon steels, on the other hand, will result in a dull and mottled finish. A low silicon content 
will increase the growth rate of the coating, while higher-silicon steels will reduce the growth 
rate.
7
Reduction of Operating Costs
The cost of maintaining a system to prevent rust is often based on the initial purchase price, which is 
of little use in assessing the overall economics of the system. Furthermore, rust prevention systems 
can require extensive maintenance, which can cause operational stoppages and incur additional costs. 
Additionally, maintenance tasks may require the use of scaffolding and/or covers for the products or 
machinery. These variables vary according to the size and shape of the structures, which can affect 
both the cost of galvanizing and the ease of maintenance.
Reduction of operating costs during Hot Dipped Galvanized Steel can be achieved by optimizing 
the process. Continuous internal processing of the flux solution can keep the iron content of the bath 
at a minimum and reduce the production of disruptive residual products, such as zinc ash and iron 
zinc. As the cost of zinc and nickel continues to rise, these methods may offer an alternative way to 
reduce costs during galvanizing.
8
THANK YOU
 Address: 
2487 Industrial Pkwy W, Hayward, CA 94545
 Email: [email protected]
 Website: www.ussupi.com
 Phone Number: (800) 877-7672