Directions for Stainless Steel Welding

Stainless steel welding requires much attention to detail. You must know the type of stainless steel with which you are working as well as the proper preheating procedures and those associated with the post-welding process as well. You must know the proper shielding gas, the filler metal and current parameters to use in your weld. Also, you must be able to examine the type of material with which you are working to determine the best welding process for your project.

Things You'll Need

• Welding arc
• Controller computer
• Goggles
• Gloves
• Chipping hammer or grinder

Instructions

1. Read and understand all materials containing the best safety practices. Become familiar with your boss's safety rules, as well as all material data safety sheets and manufacturing rules concerning the task you are to perform.

2. Provide the sufficient ventilation you will need to perform your weld. Open a window or use a fan to minimize the inhalation of the toxic gases associated with welding.

3. Determine the design and fit of your desired weld. According to the Aufhauser website, the five basic types of joints are butt, edge, T, lap and corner.

4. Choose the welding process for the material. According to Aufhauser, you can select one of four: shielded metal arc welding, gas tungsten, flux cored and gas metal.

5. Utilize the appropriate shielding gas, depending on which one of the four welding processes you choose.

6. Select the filler metal based on the composition of the material you are welding.

7. Set the current parameters. Choose either direct current (DC) or alternating current (AC) based on the diameter of the electrodes and the thickness of the metal you are welding. D15 electrodes use DC, while D16 takes AC or DC.

8. Clean the base metal. Use a stainless steel brush to remove burrs and oxides. Wear gloves to prevent oil and dirt from appearing on the surface of your weld.

9. Bring base metal to the necessary temperature. Preheat if your metal contains carbon, iron or martensite.

10. Use adequate welding techniques. Utilize jigs or fixtures to hold your work in place. Square off all adjoining edges. Work at a steady pace to ensure a smooth weld. Hold your welding instrument over your project until the gas stops.

11. Follow all postwelding cleaning and heating protocol. According to the Aufhauser website, postheating is necessary to avoid cracking, especially if you work with thick metals. Check for slag residue. Remove with a chipping hammer or grinder.

References

• Aufhauser: Stainless Steel Welding Procedures
• Key to Metals: Welding of Stainless Steels
• Spiusa: Martensitic Grades
• Flowserve: Post Weld Heat Treatment of Socket Weld Valves