Last Updated on Mar 18, 2022
It’s easy to see why stainless steel is a popular choice for welding. Stainless steel does not rust or corrode even when subjected to the elements, unlike other types of steel. On the other hand, stainless steel might tarnish and lose its resistance to corrosion after welding. Stainless steel projects need to be finished after welding to keep them looking their best for a long time.
In order to recover the look of welding stainless steel, what really is the best method of doing so? The discolored coating must be removed before the steel can be polished. Chemical baths, pickling pastes, electrochemical finishing and hand grinding are all options for removing this layer. It’s impossible to say which one is better than the other.
What is the Purpose of Weld Cleaning?
After TIG, MIG, and other welding methods, it is necessary to perform weld cleaning to improve the metal’s resistance to corrosion.
Rust and cross-contamination are only two examples of the many forms of deterioration that metal surfaces and welds are prone to.
Discoloration and heat tints are common once certain welding procedures are used. A thorough cleaning and final polish may alleviate the issues in both cases.
What Is Causing Corrosion?
When metal surfaces are being prepared for welding, they are exposed to various atmospheric factors such as oxygen and humidity, providing ideal circumstances for rusting to occur quickly.
In order to preserve the structural integrity and other qualities of steel constructions, weld cleaning (and polishing) is essential. Additional advantages of cleaning metal surfaces include improved durability and a more appealing look.
Cleaning Methods for Welds
Stainless steel may be cleaned mechanically, chemically, or electrochemically after welding. The primary functions of brushing are preparation of the surface and removal of particles after cleaning.
Mechanical Weld Cleaning
Grinding machines and abrasives are used in mechanical weld cleaning to eliminate the top layer of rust and other flaws from the metal. Time-consuming, this method seldom yields clean results with the aesthetic value required.
Chemical Weld Cleaning
When it comes to weld cleaning, pickling paste is the most usually utilized chemical. The procedure is quite efficient, but it is becoming more controversial because of its evident flaws.
Pickling paste includes hydrofluoric, nitric, and sulfur acids, which pose a significant health risk. A person’s skin and internal organs may be permanently damaged by all of them, which is why they’re so harmful.
Pickling paste can only be used by trained professionals. The whole body must also be covered to prevent any skin contact with the acid. As a result, weld cleaning takes on a whole new layer of difficulty.
In addition to causing immediate harm to the human body, pickling paste has a harmful influence on the environment. The ecology is in grave danger from pollution in the air and garbage buildup.
Electrochemical Weld Cleaning
Electrochemical weld cleaning is quicker and more successful compared to the other two approaches. There is no considerable risk to human health as a result of its use.
A clean weld is always the result of using this technique to remove contaminants, corrosion, and other types of impurities from metal surfaces.
Cleaning Using Electrochemical Methods
Electrolytic cleaning is a straightforward procedure.
A moderate electrolytic cleaning solution is used to clean the welded metal component. The electrolytic solution creates an electric circuit by conducting electricity (AC/DC) through it. This technique removes discoloration and creates a suitable passivation by eliminating impurities from the weld.
Different Electrochemical Cleaning Methods
Electrochemical cleaning is utilized in welding in two ways. For the removal of discoloration, electricity is sent through the weld in both methods.
- In the first method, a carbon brush is used to apply electrolytic liquids to the workpiece. Clean, uniform surfaces are produced when electricity flows through metal and interacts with an electrolytic liquid.
- Electrolytic baths are used in the second approach when metal pieces are submerged in electrolytic fluids to oxidize them. When electricity travels through this combination, welding contaminants or rust are removed from the surface.
Advantages of Electrochemical Weld Cleaning
Weld cleaning using electrochemical devices has the following advantages:
- Flexibility. The portability of electrochemical cleaning systems means that they may be used anywhere, even outside of a controlled environment.
- Safety. Professionals and amateurs may use electrolytic fluids since they only include a weak phosphoric acid (in soft drinks). Most of the time, protective gear (save for gloves) is not essential.
- Speed of execution. The cleaning of electrochemical welds is quite quick. Cleaning and passivating the surface at the same time is possible with high-quality machinery.
- A high level of corrosion resistance. According to our findings, electrochemical cleaning seems to provide the highest corrosion resistance.
Electrochemical Weld Cleaning for Stainless Steel
When it comes to cleaning welding stainless steel, electrochemical weld cleaning excels. Stainless steel is a popular choice for welders because of its greater durability and resistance to corrosion. After fabrication, they are looking for a technique to keep these exquisite steel properties intact.
Stainless steel outperforms all other steel alloys because of its superior corrosion resistance and structural integrity. However, it still has a long way to go before it is rust-proof. The integrity of even stainless steel might be weakened if you don’t thoroughly clean the surface after you complete welding.
The mechanical procedure is time-consuming and unsuccessful. Even while pickling is more efficient, it is riskier for human health. A safe and rapid alternative to these approaches is electrochemical cleaning. As an added benefit, it offers higher resistance against corrosion and rust.
Welding stainless steel benefit greatly from this procedure. Fast and effective removal and prevention of rust and other contaminants are ensured. Without the necessary tools in place, this cannot be accomplished.