How To TIG Weld Stainless Steel Like A Pro

Table of Contents 1. Critical Applications Of Stainless Steel In Welding 2. The First Step In Mastering TIG Welding Techniques For Stainless Steel 3. Applying Professionally Tuned Equipment Settings 4. A Return To The Basics: TIG Welding For Stainless Steel Projects 5. Managing The In-Action TIG Welding Process 6. Solving Stainless Steel Weldability Complications 7.Tig Weld Stainless Steel Like A Pro - FAQ

TIG welding is difficult at the best of times. It’s a skill that requires experience, coordination, and no small amount of multitasking expertise. Add stainless steel to the mix as the source workpiece, and well, the whole process becomes that much harder to accomplish with any amount of precision.

Typically, then, employers hire TIG welding pros for stainless steel jobs. It just makes sense to do so. True, that action could put the brakes on an upcoming project, but the long-term gains are undeniable. After all, stainless steel welding isn’t exactly rare. This is a common metal, a rigid, structurally dense alloy that’s made its way into every corner of life. The work done on this kind of project simply cannot be undermined by a substandard weld. A poorly welded stainless steel structure might even be warped by weld heat or dotted with rust. What an unforgivable sin that would be.

 

Critical Applications Of Stainless Steel In Welding

Stainless steel isn’t a single metal. It’s actually a versatile family of alloys that are found everywhere. This includes the construction industry, pressure vessels, and piping systems. Furthermore, its ductility and strength make it an ideal choice for the kind of large-scale construction projects that require strong and durable support materials.

Source: https://www.bsstainless.com/stainless-steel-in-construction-five-famous

Even kitchenware and food industry components use some variety of stainless steel. Grades that are corrosion-resistant and chemically neutral are favored in such commercial applications. Out in oil fields and other harsh industrial settings, ANSI and SAE graded steels deliver superior heat tolerance and durability, plus a degree of liquid/gas corrosion resistivity. So, what’s the answer? When stainless steel workpieces require welding, what are the options? A Tooliom TIG Dual Voltage TL-200T 2-in-1 Welding Machine is one possibility, but even a fine machine like this requires someone who has overcome the challenges associated with stainless steel welding.  

 

TIG/Stick High Frequency Dual Voltage TL-200T 2 in 1 Welding Machine｜Tooliom

The First Step In Mastering TIG Welding Techniques For Stainless Steel

Problematically, the alloy encompasses a huge array of graded amalgams. To create the many members of this metallic family, trace metals are incorporated during the heat treatment stage. Additives like nickel and manganese provide various stainless steel grades with unique mechanical and chemical properties. The crux of the matter is this: while desirable to engineers and builders, those properties can complicate TIG welding operations.

It’s the job of a TIG welding pro to know those alloy properties and to know and apply techniques that expressly target stainless steel. Equipment selection and settings are also critical, but a real pro knows that there’s an initial step to conduct before those requirements can be brought to bear on the job. Cleaning and prepping, that’s the key, the means to unlocking the whole process.

The prep process guide:

• Clean the metallic surface of grease, oil, corrosion, and other contaminants
• Take the prep work further. Use wire brushes and a grinding tool to smooth surfaces
• Select an appropriate inert gas. Hot stainless steel heat-affected zones oxidize easily
• Select a superior welding rig. A Tooliom TIG TL-200T 2 in 1 Welding Machine is an excellent choice 

Applying Professionally Tuned Equipment Settings

Intermediate welders are capable, but they tend to take shortcuts. Perhaps they’re so experienced that they feel they know all there is to know about TIG welding, and there may be some truth to their claims, but equipment changes are always in flux. Here at Tooliom, we strive for more power, more flexibility, and many more features, too. Pros know this, which is why they carefully put the equipment manual to one side, ready for consultation.

Back with the Tooliom TL-200T, a data table is supplied so that welders can get the best out of their gear. On that table, the ideal equipment settings can easily be intuited. The amperage and voltage are there, all the better to assure deep root fusion. Electrode polarity and filler metal selection are both clearly printed as well. Tungsten cleaning and sharpening, duty cycle settings, and shielding gas volume, all of these variables are controllable. This is where the multitasking aspect comes to the fore and those many settings are adjusted with confidence by a pro welder.

TL-200_Panel_Annotation｜Tooliom

By the way, referring back to that manual, there’s a troubleshooting guide at the back of the book. It’ll keep a seasoned welding professional on the straight-and-narrow should an unforeseen issue crop up during a stainless steel welding operation.

On seeking high-quality, professional results here are some tips and tricks that will help pros avoid common pitfalls:

• Use a tungsten rod with the correct diameter (See manual data table)
• Keep the tungsten tip clean and sharp
• Use 100% Argon as the shield gas
• Manage applied thermal energy
• Establish a good, clean electrical ground
• Use DCEN (DC electrical negative)

 

Correct and incorrect tungsten grinding direction relative to the grinding wheel.

Source:https://yeswelder.com/blogs/yeswelder/how-to-shape-tungsten-electrode-for-tig-welding-and-why?_pos=3&_sid=0d66dcfa8&_ss=r

A Return To The Basics: TIG Welding For Stainless Steel Projects

TIG welding, or tungsten inert gas welding, is a versatile type of arc welding that uses tungsten electrodes and inert argon gas to create a weld pool. It’s suitable for stainless steel because TIG welding machines produce precise, clean welds. However, and this is the main reason for writing this article, TIG welding also requires a lot of skill and practice, as well as proper equipment and settings. So far, the Tooliom TL-200T has been recommended as an ideal partner for pro TIG welders, especially when the workpiece is made of stainless steel. The Tooliom TL-200M is also available, and it adds MIG (Metal Inert Gas) welding capabilities into the mix.

Source: https://www.technoxmachine.com/blog/mig-vs-tig-welding/

Whichever machine the welder selects, there are a few other matters to attend to before an arc can be struck. The workpiece needs to be prepared, as noted earlier. The appropriate tungsten electrode is picked, cleaned, and sharpened. Is the arc circuit set correctly? The pro welder will check by adjusting the current and voltage and then having a quick look to see if the ground clamp is tight. Finally, the argon gas flows around the weld puddle, as set by the regulator. The welder is protected, dressed in gloves and a welding helmet, plus any other fire retardant clothing.

Mig/Stick Welding Gloves ｜Tooliom

At this point, there’s a lot to manage. The controls, the gas regulator, the arc consistency and puddle size, they all need to be carefully monitored. One way to simplify things a little is to add a foot pedal. Machine presets are also likely available from the equipment control panel, but fine adjustments will need to be made on-the-fly as the electrode travel speed varies over the weld seam.

With the DCEN (Direct Current Electrode Negative) setup properly locked in, the cables are connected in the right configuration, all safety measures are in place, and the job can begin.

 

Managing The In-Action TIG Welding Process 

The goal now is to lay down a clean, spatter-free joint. The fusion process should penetrate deep to the root, the electrode travel swiftly, and the surface appearance of that weld apply in a manner that’ll satisfy a welding inspector. With no oxidization, little to no discoloration, and no workpiece warping either, the final result is clean and structurally firm.

Source: https://www.wcwelding.com/fusion-welding.html

There’s no reason these goals can’t be accommodated. If the welding machine and prep work have both been done properly, all that’s left to question is the skill of the welder. This individual must be well-versed in the unique challenges that will come to hand when working with a TIG welding machine on a stainless steel project. Training is important here, as is experienced in past projects on this potentially hard-to-weld alloy. Remember, stainless steel parts are common. They’re particularly common in structural work, also in engineering projects, and pipework, too. Austenitic stainless steels are popular. They’re a family of alloys that can be welded, but their microcrystalline structures will alter if they’re exposed to copious quantities of thermal energy.

Now, because of weld geometry issues and a matching reduction of travel speed, austenitic steels will absorb great amounts of heat. Pro welders should be aware of this problem. The metal will warp if it can’t dissipate this energy. Rich in chromium, the alloy is essentially corrosion-resistant, but that trace element can be depleted if the weld runs too hot. Chromium depletion problems in stainless steel typically show up as corrosion.

Source: https://www.huntingdonfusion.com/index.php/en/technical-support/weldingknowledge/3719-welding-knowledge-part-4

At the end of the day, stainless steel components possess very good heat retainer mechanisms. And they can’t readily dissipate this thermal energy. Corrosion issues, warping, chromium depletion, and alloy embrittlement problems, too, they’re all possible if the job isn’t done properly. Welding experts can certainly manage these issues, but that’s a skill that becomes ever harder to master when other families of stainless steel are added. Austenitic alloys are one such group, then there are ferritic steels, duplex, and martensitic as well. That, unfortunately, is a large number of graded stainless steels, all of which have their own mechanical and physical properties, all of which react in one way or another to large quantities of heat.

Solving Stainless Steel Weldability Complications

By maintaining travel speed, most problems are immediately solved. There’s no build-up of thermal energy, and what little heat is present in the seam will dissipate without changing the alloy’s microcrystalline structure. The use of the correct filler metal is also critical. If the grade of the stainless steel is known, say, it’s a 316 austenitic, then a matching 316L filler would be selected. Similarly, this time with a martensitic alloy, this type of stainless steel contains more carbon. It’s one of the harder-to-weld alloys, and it’s susceptible to hydrogen cracking. Pro welders address these issues by using pre-heat work, matching fillers, and heat treatment.

Source: https://www.researchgate.net/figure/Solidification-cracking-in-GMAW-Fig3-Hydrogen-induced-cracking-in-HY-80-steel_fig1_263656906

Frankly, welders aren’t chemists, they’re not expected to understand the changes that occur when the microcrystalline structure of an austenitic or martensitic alloy transforms in some adverse way. But they do have an intimate understanding of their welding equipment, which means they can regulate the travel speed and the amount of heat that’ll linger in the HAZ (Heat Affected Zone). As such, pros input settings that’ll ensure a satisfactory travel speed, and they also use the appropriate fillers. All-in-all, pore-free welds, made deep to the root, are absolutely achievable when pros are working on a stainless steel welding project.

As mind-numbingly complicated as all of these stainless steel welding factors might seem, there’s a silver lining. Yes, pro welders are preferred here, and there’s also a preference for a top-notch welding machine, such as the Tooliom MIG/Stick/TIG Multi-Process Welder TL-200M 3-in-1, but then there’s the common sense factor, too. Imagine a stainless steel job running along without incident on one part of a major project. A carbon steel job operates nearby. There’s perhaps a temptation to share tools. Don’t do this. By sharing a tool between the two jobs, iron might be introduced into the stainless steel weldment, thus inserting a source of rust into the otherwise clean joint. That’s common sense, it’s a powerful tool.

Besides simple common sense, it’s a case of knuckling down and doing the job right. There are too many grades of stainless steel to custom-build a weld settings plan for each one. Instead, implement a professionally conducted stainless steel work plan. Do keep settings for a well-regulated travel speed. Do the same for the filler metals and shield gas; keep a matching filler on hand and use 100% inert argon gas at all times. A direct current electrode negative arc is a must, plus the associated current and voltage settings for a narrow, precision-applied bead width. 

Source: https://weldguru.com/ac-vs-dc-welding/

In conclusion, don’t be deterred by alloy issues. As long as the welder is a pro, someone who is familiar with these unique challenges, a capable TIG welding machine will lay down precise, clean welds. Proper preparation is the first step, along with an informed equipment setup routine. Then it’s a matter of letting experience and training take over. If that training isn’t fully implemented, don’t blame the gear. Rather, go back to the beginning and practice, practice, PRACTICE.

It’s worth noting, now that the end of this post is imminent, it’s easier to implement a good TIG training program, but it’s not so easy to replace an expensive stainless steel part if it is warped or corroded due to a substandard welding operation.

Clean stainless steel weld

Source: https://www.weldingtipsandtricks.com/stainless-steel-welding-tips.html

Tig Weld Stainless Steel Like A Pro - FAQ

What are application scenarios of stainless steel ?

Stainless Steel is uesd in the construction industry, pressure vessels, and piping systems.Furthermore, its ductility and strength make it an ideal choice for the kind of large-scale construction projects that require strong and durable support materials.

What is the first steps in mastering TIG welding techniques for stainless steel and how to do it ?

Cleaning and prepping.

• Clean the metallic surface of grease, oil, corrosion and other contaminants
• Take the prep work further. Use wire brushes and a grinding tool to smooth surfaces
• Select an appropriate inert gas. Hot stainless steel heat affected zones oxidize easily
• Select a superior welding rig. A Tooliom TIG TL-200T 2 in 1 Welding Machine is an excellent choice

How to avoid some mistakes (pitfalls) in order to get high-quality results ?

• Use a tungsten rod with the correct diameter (See manual data table)
• Keep the tungsten tip clean and sharp
• Use 100% Argon as the shield gas
• Manage applied thermal energy
• Establish a good, clean electrical ground
• Use DCEN (DC electrical negative)