How To Use Argon Gas In Welding
Argon is an inert shielding gas used to protect a weld from air contamination. When air contacts the molten weld puddle, the air reacts with the metal. This causes porosity to form in the weld. Porosity is small holes that form in the weld, reducing the bond between the base metal and the weld. Porosity laden welds do not have the same structural strength as a solid weld. Argon, being heavier than air, sits on the weld puddle longer than other types of inert shielding gases, allowing ample time for the molten weld puddle to cool
1. Place the bottle of argon gas onto the TIG welder. Fasten the safety change around the argon bottle to secure it to the welder. Remove the screw cap from the bottle of argon.
2. Crack the valve of the argon bottle, by quickly opening and closing the valve handle located at the top of the bottle to blow contaminates from the interior of the valve.
3. Thread the regulator nut onto the argon bottle. Turn the nut clockwise to secure the regulator nut to the argon bottle. Set the adjustable wrench to the size of the regulator nut. Tighten the regulator nut to seal the connection between the regulator and the argon bottle.
4. Open the valve on the argon bottle. Check the connection between the bottle and the regulator for leaks. Examine the feeder hose that leads from the regulator to the welder for leaks or signs of damage.
5. Turn on the welder. Depress the foot peddle or trigger for the TIG welder to activate the gas flow. Adjust the gas flow meter to provide the correct gas flow for the current working conditions. Increase the gas flow rate if you are working in windy conditions that can cause the argon to dissipate from the weld puddle.
6. Place the two pieces of prepared stainless steel test pieces flat on a welding table, with a 1/16th inch gap between the joint you intend to weld.
7. Put on the welding hood and thin leather welding gloves. Attach the ground clamp from the welding machine to the welding table. Place the tip of the tungsten located in the TIG torch 1/8th of an inch away from the weld joint, with the tungsten set slightly to off the 1/16th inch weld gap that you left between the stainless steel test pieces in step 6.
8. Lower your welding hood. Depress the foot pedal or trigger to activate the welding machine. Fuse the two pieces of stainless steel together with a small tack. Release the foot pedal. Do not move the TIG torch until the argon gas stops flowing. Place tacks every 1/2 of an inch along the length of the test weld joint.
9. Pick up a piece of stainless steel filler rod. Place the filler rod parallel to the weld joint, sitting at a 15 degree angle from the weld joint. With the TIG torch sitting 30 degrees from the weld joint, lower your welding hood, and depress the foot pedal.
10. Feed the filler rod into the arc of the TIG torch. Place the molten filler rod into the weld joint. Move the torch 1/16th to 1/8th of an inch after you feed the filler rod into the weld joint. Watch the weld puddle for sparking or lifting, both signs of porosity.
11. Allow the weld joint to cool thoroughly before handling. Examine the final weld joint to ensure that there is no porosity located within the weld.