Today, stainless steel remains even more popular because of its valuable characteristics. These include the resistance to different kinds of liquid, chemical and gaseous corrosion. It is also known for its robust and long-lasting properties.
When it comes to welding, stainless steel is also a popular choice. Learning how to weld using stainless steel may seem like a difficult process to others. But understanding the basics regarding welding stainless steel will help you get started. There are just a few aspects that welders should consider. With this blog post, they will learn about the basics of welding stainless steel. Read more here.
Common techniques for welding stainless steel
Selecting the process for welding stainless steel will depend on the finish of the material used and thickness of the metal. Although there are several methods for welding stainless steel, most welders only used these three techniques. These are as follows:
1. TIG welding (Gas Tungsten Arc welding)
TIG or Tungsten Inert Gas welding is the most common stainless steel welding process nowadays. This method is ideal when welding critical joints. It is also widely used in industries where fine and precise welds are required.
Generally, this method uses argon gas that is mixed with helium, hydrogen and nitrogen. Argon gas is used since it protects and cools down the tungsten. Aside from that, it prevents oxidation. Lesser smoke is also released by argon gas compared to other gases.
2. Resistance or spot welding
As the name suggests, this is the welding process for spot or seam welding. Spot welding is known to be the most economical technique of welding. Moreover, the equipment used for resistance welding is very versatile. Hence, it is perfect to use for small and large welding projects.
Resistance welding uses an electrical current to melt metal edges and bond them together. This technique is known to be a productive choice for metals with a low melting point. This is because it can be easily modified to prevent metal distortion.
3. MIG welding (Gas metal arc welding)
This method is a semi-automatic welding process that provides durable bonding of two pieces of stainless steel especially when it is done correctly.
MIG welding allows the welder to utilise a pulsed current supply. In this way, it will be easier to weld the hard-to-reach corners on those intricate stainless steel projects.
Gathering tools and supplies
Welding stainless steel specifically using MIG method requires particular tools and materials to finish the task. Here are some of the equipment that must be prepared for any welding job.
- Welding machine – this machine is essential for producing reliable and solid stainless steel welds. For a MIG welding machine, it is vital to look for parts such as welding gun and sample welding wire.
- Welding gun – as mentioned above, welding machines usually come with a welding gun. For finer control and specific tasks, the welding gun can be upgraded.
- Gun liner – this tool protects the welding gun. It also allows welders to switch between various types of metal wire for particular welding jobs.
- Wire feeder – this device is only needed if the project requires a lot of welding or if someone is working in a specialised facility.
- Welding wire – an appropriate welding wire for stainless steel should be used. You should check the welding machine or dedicated wire feeder to know what welding wire to be used.
- Cleaning brush – to help prepare the workpiece for a better and durable weld, a metal cleaning and scraping brush is needed.
- Shielding gas – a combination of argon, helium and carbon dioxide can be used as shielding gas.
Tips for welding stainless steel
To ensure a safe and long-lasting stainless steel welding, here are some useful tips that you can follow.
1. Make sure to clean the surfaces of stainless steel prior to welding
Stainless steel is prone to contamination by high-carbon steels and other metals. When it is exposed to these metals, its corrosion resistance may be reduced.
Aside from that, cleaning the surface of the stainless steel will strengthen the weld as a whole. If you are cleaning with a wire brush, make sure not to use it with other metal surfaces. This is because there may be microscopic particles from other metals that can penetrate on the stainless steel surface while cleaning. In this case, specialised pickling and cleaning treatments should be considered to prevent issues in the future.
2. Prepare the tools needed
Getting a good weld means starting the process right each time. Always check the equipment, wire supply and welding machine amperage and voltage before anything else. In case a quick change is required, extra wires, consumables and gun tips should be accessible while working.
3. Select filler material that is similar to the welded metals
Choosing the right filler material is important to maintain the corrosion resistance of the stainless steel. To pick the right one, consider the grades of steel and suffixes involved.
4. Work in a well-ventilated area
It is recommended to work in an open garage to provide welders plenty of ventilation. If there is no fresh air in the workplace, task-specific exhaust systems can be used. Moreover, there should be ample lighting in the work space to perform satisfactorily.
5. Wear the right personal protective equipment (PPE)
In any welding jobs, it is crucial to wear suitable personal protective clothing. This is to ensure that the welder is safe against hazardous incidents such as sparks, burns, spatter, radiation and electric shock. Wearing appropriate protective gear is a safety practice. It is also required by regulatory agencies.
Welding with stainless steel can be difficult especially if you don’t have the right tools, equipment, skills and knowledge. Thus, it is vital to take your time and have some research beforehand. Understanding the basics of welding stainless steel is important to obtain a good and valuable result in stainless steel fabrication. And this blog post will be your guide to achieve an outstanding workpiece.
If you need help when it comes to your metal fabrication projects, don’t hesitate to call your local metal fabrication experts.