Welding is a process that has been used for centuries in metal assembly works. Although the processes, metals and techniques used have been improving over the years; careless mistakes still happen in the welding process which leads to poor outcome of the process. One of the most common of these mistakes is poor preparation of the end metal, and when this happens, the resultant metal will have the following defects.
The presence of cracks
Cracks occur because of excessive mechanical stress in the bead of the weld. Hot cracking happens when you are still welding the metal, or before the solidification process is complete. The type of weld assembly determines the mechanical stress because narrow bevels lead to extremely high levels of mechanical stress. On the other hand, cold cracking happens hours or days after the metal has solidified. It mainly occurs because of three factors; residual mechanical stress in the metal, the presence of diffusible hydrogen and also the temper structure. Proper preparation means getting the right tools for the job and using the right welding processes to avoid cracking.
Formation of blowholes
When the material is not prepared well, it will also form blowholes. Water, grease and other substances sometimes appear on the receiving metal, which leads to formation of bubbles that get trapped inside the bead. The easiest way to avoid this problem is using dry machining to prepare the end of the metal to be welded together.
Contamination of the iron
Iron contamination is a problem that affects stainless steel parts when getting welded together. If the steel comes into contact with iron particles in an electric medium, the result is galvanic corrosion, especially when damp air is the conducting medium. When the welding has been completed, the layer which was exposed to galvanic corrosion will deteriorate with time until the metal is weak enough and it starts pitting. It is important to check the equipment being used in the welding process to make sure that it does not cause any type of contamination.
Other issues which may occur when the material is not well-prepped include incomplete penetration or at times, excessive penetration, lack of fusion and the gradual deterioration of the properties of the material. All these are problems which can be avoided by simply getting the right methods to prepare the end metal before welding. You can also consult experts and get the right methods to use when welding to avoid complications. For more information, contact companies like Burnback Welding Equip Services.Share