In welding, porosity is caused by contaminants or gases that get absorbed by the melted metal. Even if the resulting cavity doesn’t dramatically weaken the weld, it does ruin its finish. Here are a few tips to help you prevent this issue.

How to Minimize Porosity in Your Welds

1. Clean the Surfaces

Even if your welding technique is perfect, impurities on the surface can contaminate the joint and create irregularities.

Wipe every metal before you start welding to remove dust, shavings, hand grease, and other debris.

2. Check the Gas Flow

Both gas metal arc and gas tungsten arc welding rely on inert gases to protect the weld while the metal cools.

If your carbon dioxide, helium, or argon rates are too low, atmospheric gas and other impurities could contaminate the area and create cavities. Check that the gas flow rate matches the manufacturer’s instructions to prevent this.

3. Inspect Your Equipment

Even if your gas flow is correct, a cracked hose or worn gasket can allow atmospheric gas into the weld. Built-up dirt on the weld gun’s tip can also fall into the pool, creating cavities.

If you notice uneven welds, inspect all of your equipment for dirt and damage before striking an arc.

4. Maintain the Correct Distance

Holding the tip of your weld gun too far from the surface decreases the protection provided by your shielding gas.

For most short-circuit gas metal arc applications, hold the tool up to half an inch away from the metal. If you’re using a spray technique, the tip should be up to 1 inch above the work surface.

5. Eliminate Drafts

Welding rooms can get extremely hot, but avoid opening a door or turning on a fan. Even a slight breeze can disrupt the bubbles of shielding gases, allowing contaminants to enter the weld.

When working outdoors, use your body to block the wind and protect the weld from airborne particles.

 

Whether you’re a DIY enthusiast or licensed professional, Wayne Oxygen & Welding Supply Co. offers all welding supplies you need. With locations in Waynesboro, Charlottesville, and Harrisonburg, VA, they carry products from Lincoln Electric Company® and Miller Electric Manufacturing®. Visit their website for an overview of their products. To ask about their stock, call (540) 942-4145 to reach Waynesboro, (434) 295-2334 in Charlottesville, or (540) 434-1235 to speak with an expert in Harrisonburg.