7 Welding Defects: What Are the Causes and What Can You Do About Them?
Welding defects are more common than manufacturers would like them to be. To reduce welding defects, it is important to understand the causes and eliminate them as much as possible. Studying the 7 most common welding defects and what causes them can lead to better manufacturing processes and better products.
When a Company Specializes in Fabricating and Welding
Companies that need a special product or machine fabricated often turn to a high-quality, dependable company to do the job for them. Domestic and global manufacturing companies include a Heavy Duty V Roller Manufacturer like MCMILLANCO with the correct type of equipment and manufacturing capabilities.
7 of the Most Common Welding Defects
1. Weld cracks are a serious defect that comes as a hot crack, a cold crack, or a crater crack. These visible cracks will cause the project to not be accepted. These cracks can be avoided by required preheating of metal, proper cooling of the area welded, better joint design, use of better welding speed and amperage current, and other good practices.
2. Weld porosity is caused by contamination of the weld by trapped gases and weakens the weld. This can be prevented by making sure clean materials are used, the correct arc distance, using correct electrodes, and a better welding technique.
3. An undercut weld imperfection involves the formation of grooves at weld toes or edges. This can be corrected by using a better technique with proper electrode angle, shorter arc length, and a multipass technique.
4. A weld with incomplete fusion causes a lack of adhesion between the base metal and the weld metal, creating a gap in the joint and weakness. This problem can be avoided with correct welding current, cleaning the material to be welded better, reducing deposition rate, and avoiding flooding the arc with a molten pool.
5. The weld has incomplete penetration happens when not enough welding material is used and there is an incomplete filling of the weld joint. This problem can be avoided with use of better-sized electrodes, reduced arc speed, proper alignment, and use of the best joint geometry.
6. Welds with slag inclusion are easily spotted and are caused by slag or vitreous material invading the welding material. That weakens the weld. This can be avoided with increased current density, slower cooling, better electrode angle, better welding speed, and removing slag from a previous bead.
7. Weld splatter gives the weld a messy look and is most common in gas metal arc welding. This is a problem that is hard to avoid but can be reduced by cleaning surfaces before welding, reducing the arc length, better weld current adjustment, proper polarity, and all-around better technique.
Avoiding Imperfect Welds For Safer Products
Welding defects are any flaw that compromises the usefulness and durability of a weld. All types of welding defects must be avoided by using the most advanced welding equipment and techniques. This is no place to cut costs or corners. Defects can be classified as critical or noncritical. Experienced, well-trained welding equipment operators are essential. The company hired to do welding jobs must have an excellent reputation and offer product guarantees and extensive testing of finished welds.
There are effective testing methods to discover all the possible welding defects. When defects are discovered, the welds must be removed, the surfaces cleaned, and new welds made. Some tests include liquid penetrant testing, magnetic particle inspection, and radiographic and ultrasound testing.