Why Welders Are Purging Pipes and Tubes Before Welding
Creating a strong, long-lasting weld requires a clean joint on your metal workpiece. When it comes to TIG welding uniquely shaped materials or pipe welding jobs, purging the metal of oxygen with an inert gas can keep the weld fully protected from oxidation that could lead to corrosion. The purging process may use a kit that helps seal the gas in the pipe prior to welding or a vacuum chamber that keeps the gas contained.
Before you pick up a cannister of gas at Baker’s Gas and Welding, here are a few tips to consider about purging steel tubes and other materials for welding:
Why Purging Before Welding?
Is it enough to clean your workpiece with a wire brush and a cleaning solution before TIG welding with a shielding gas? Maybe. The challenge is that certain weld joints will oxidize due to their orientation or design, minimizing the impact of the shielding gas.
Purging the weld joint prior to tube or pipe welding also eliminates the need to remove oxidation after welding–which is going to be quite hard to do in most pipe joints! Even if you can reach the weld joint inside of a pipe or tube, it is extremely time consuming to remove it effectively and it’s hardly a sure bet since visual inspections are nearly impossible. You’ll save a lot of time and aggravation if you purge the weld joint ahead of time.
Materials that Require Purging for Welding
While purging is frequently used on steel tubes, there are other materials that may benefit from the gas purging process. For instance, TIG welding on stainless steel, titanium and other corrosion-resistant materials may all benefit from this process.
If you’re building a tube chassis, shelves, or a fence, purging with gas may help remove impurities as you join the materials together.
Gases Used for Purging Before Welding
Most welders already have argon gas around their shops, so it’s convenient that most welders who purge steel tubes or other materials turn to argon for purging before welding. However, others forms of inert gas can work depending on the materials and availability of gas. Besides argon, you can use helium or nitrogen. In the case of welding stainless steel, stick with argon instead of nitrogen.
How Effective Is a Purge?
Purging a pipe or tube prior to welding helps take the guess work out of the process, assuring a clean weld without oxidation. However, if you aren’t sure about the effectiveness of the purge process itself, you can pick up a weld purge monitor that is hand held and battery operated.
Using a monitor to measure the effectiveness of your purge can give you the peace of mind you need to know that your weld is going to be effective and clean.
Welding Supplies at Baker’s Gas and Welding
Pick up everything you need to weld and purge at Baker’s Gas and Welding, where we offer competitive prices on gas canisters and welding supplies. We have you covered for welding electrodes, welders, and welding safety gear.