Welding is a complex procedure that requires extensive experience and a specific set of skills. Attempting to weld without proper expertise can result in a wide range of defects that can put projects at risk, resulting in time consuming repairs. In this blog, we are exploring the most common types of welding defects and providing you with 5 tips on how to prevent them.
1 - Cracks
One of the worst types of welding defects, cracks can get bigger quickly, compromising the integrity of the structure you are working on. Cracks are usually caused by rigid joints that prevent the metal from contracting or expanding or when you use hydrogen when welding ferrous metals, such as stainless steel.
Preventing Cracks
To prevent cracks from happening, it is important to consider materials that have similar coefficients of thermal expansion, and that you preheat the base metal before you start welding.
2 - Undercuts
Undercuts are typically formed when excessive current is used during the welding process, leading the edges to melt. Another reason for why undercuts happen is not using enough filler material, which results in a reduced cross-section. Undercuts can lead to weakened welds and compromise structural integrity.
Avoiding Undercuts
Undercuts can be avoided with proper welding techniques. You can try maintaining a consistent arch length, voltage and travel speed as well as using a 30 to 45-degree electrode angle in the process.
3 - Burn-Thorough
Burn-though happens when excessive heat allows the weld metal to melt and go through the base material, leaving an open hole exposed. It usually happens during the welding of thin metals.
How to Prevent Burn-through
In order to avoid burn-through, it is recommended that you reduce the voltage or the wire feed speed to generate less heat. Adjusting the travel angle to a less steep position can better distribute the energy of the weld, which also helps avoid the defect.
4 - Porosity
This is a very common problem that happens in welds. It’s the result of contaminants or gases being absorbed into the weld puddle, leading to the formation of small holes that can significantly affect the integrity of the weld. Some of the causes of porosity include unclean welding surfaces, lack of shielding gas and improper technique.
Preventing Porosity
To avoid porosity in your welding, make sure you have a clean weld surface and that you use the adequate gas flow rate for proper shielding.
5 - Lack of Fusion
Incomplete fusion happens when the weld metal is not entirely fused with the joint, which leads to the formation of gaps in the weld zone. This is usually caused by lack of heat input, which prevents metals from melting completely.
Avoiding Lack of Fusion
In most cases, increasing the welding current may be enough to provide additional heat and prevent incomplete fusion. Changing and adapting welding positions may also contribute to a better and more reliable weld.
Professional Welding Services in Edmonton
Welding projects require proper expertise and skilled welders to ensure the integrity of the materials involved in the process. If you are looking for experienced professionals that can offer reliable welding services, Advantage Manufacturing Ltd is here to help. Don’t hesitate to give us a call and let us provide you with the welding solution you need. Reach out to us!