Welding is the process of permanently joining two metals together by heating them. It can be used in all areas: from home repairs, yachts or cars to making crafts. Welding is slightly different for each type of metal, including stainless steel. Read this article to learn the specifics of how to weld stainless steel properly.
Steps
Step 1. Put on the proper protective gear
Wear a long-sleeved shirt and pants that cover your skin as best as possible. Always wear eye protection, gloves and, if desired, use hearing protection
Step 2. Determine the best way to join basic metal products
- The most common types of welded joint are T-joint, butt joint, lap joint, fillet joint and butt joint.
- When choosing the type of joint, take into account the thickness of the metal to be welded, the accessibility of the area for the joint and the required strength of the weld.
Step 3. Secure the metal piece with clamps
Step 4. Choose the most suitable welding method for your stainless steel product
- This can be a shielded manual arc welding method, also known as RDS or electrode-assisted welding.
- Argon arc welding, also known as ADS.
- Powder arc welding known as FCAW.
- Gas-shielded arc welding known as semiautomatic. This process is divided into two different methods: short circuit and cathodic sputtering.
Step 5. Select a compatible inert shielding gas
In some cases, such as RDS, an inert shielding gas is not needed. For other methods, either argon or helium or combinations of gases in varying proportions can be used
Step 6. Select the filler metal used to weld the stainless steel
If both metals to be bonded are the same, the filler metal should reflect the composition of those base metals. If the metals differ, the filler metal should be the one that is less prone to cracking and is most compatible with the base metal
Step 7. Clean the stainless steel base metal
- Cleaning eliminates the possibility of formation of oxides on the base metal. The entire surface of the base metal must be carefully cleaned with a stainless steel wire brush to remove any existing oxides and burrs.
- Wear gloves to avoid passing the oil from your hands onto the stainless steel.
Step 8. Preheat the stainless steel to room temperature
If the stainless steel is austenitic, no preheating is necessary. Preheat material if working with martensitic or ferritic stainless steel. Heating is also necessary if the stainless steel is very thick or high carbon
Step 9. Use a welding gun
Step 10. Apply heat after welding the stainless steel
Rapid cooling of stainless steel can cause strong internal stresses, which can lead to cracking. Post-heating is especially necessary when welding thick pieces of metal
Step 11. Remove slag from the weld, if necessary
Remove it by sanding or using a hammer.
Welding with RDS and FCAW methods can lead to the formation of slag residues
Advice
Always move the welding torch at a constant speed to ensure even weld metal
Warnings
- When welding your first products, work under supervision or with the help of someone with welding experience. This greatly reduces the likelihood of injury or material weld failure.
- Never work in a closed or unventilated area. Fumes emitted during welding can be very harmful.