Everybody wants their equipment functioning properly in order to perform a strong even weld. Performing a visual inspection of the welding equipment and material should be enough for an experienced welder to predict if everything is going to run smoothly. Unfortunately, even if the best welder is using the best equipment with great material there is a force that comes into play one cannot see. This force will cause arc blow and make even creating a simple weld a challenging task. This force is magnetism.
Magnetism can be found in all materials to an extent. This physical phenomenon is produced by the motion of electric charge, resulting in attractive and repulsive forces between objects. In every magnet there are two poles with opposite polarities, being the North Pole and the South Pole. North Poles seek North and South Poles seek South. When electrons move they create a magnetic field. Magnetic fields travel from North to South.
Ideally, when welding, one wants to demagnetize their material. This is done by making the moving electrons in the magnetic field temporarily cancel one other. One cannot permanently demagnetize material. Imagine trying to keep a leaking beach ball floating in the ocean. The ball will float when it is initially blown up, but it will need refilled repeatedly to keep it afloat.
Demagnetizing can be done by heating the material to cause it to lose its magnetic properties. Another method is striking the material to knock the poles out of alignment. These methods are often impractical because they can change the structure of the material.
The practical option for demagnetization is the “step down method”. This is done by wrapping a cable around the desired welding material. The cable is attached to a machine that reads the magnetic field. The machine then uses DC current to penetrate the material in order to randomize the poles without altering the materials structure. This will “zero out” the magnetic field, allowing an even weld to be performed.
Magnetism is a common struggle for welders and companies attempting to produce high quality products. However, demagnetizing can be easily and accurately done with the step down method. It is in a company’s best interest to demagnetize because competition for quality is always on the rise.
Posted on 08/17/2015 at 06:17:00 AM