Common Welding Mistakes And How To Avoid Them
A welder is a crucial cog in the wheel in the industries such as civil engineering, construction, aerospace, manufacturing, marine engineering, transport etc. as he is the one who puts all the pieces together. A welder has to be extremely skilled and know his work properly because even a single wrong weld has the chance of putting several lives in danger in the construction industry and impacting the bottom line in manufacturing industry.
A new welder may sometimes make mistakes due to lack of proper training, however, even experienced welders can make mistakes due to lack of practice or improper understanding of the requirements.
There are some very common welding mistakes that some welders make. Sometimes welders themselves do not realize that they are making a mistake. However, these common and small mistakes cannot be fixed easily and can have grave consequences. But all these common welding mistakes can be avoided.
Let’s take a look at some common welding mistakes and how to avoid them.
Common Welding Mistakes - Improper Welding Preparation
Before proceeding with welding power supply, it is important that all the instruments and devices of welding are in order. Welders should know beforehand the requirements of welding. They should also check part fit-up because if not monitored closely, part-fit issues may cause weld defects. Additionally, welders should ensure that the metal surfaces to be welded are free of dirt and other contaminants. A careful pre-weld preparation will decrease the chances of making mistakes.
Common Welding Mistakes – Slag Inclusion
Slag inclusions are small components trapped in the weld and are very common in the Self-Shielded Fluxcore Arc Welding (FCAW) process. The trapped particles reduce the durability of the weld. Adjusting the welding speed and adjusting the welding angle will help prevent slag inclusions. Thorough cleaning of edges and welding passes will also go a long way in preventing slag inclusions and the subsequent weld defects.
Common Welding Mistakes – Porosity
Gases such as nitrogen, oxygen and hydrogen get trapped in the metal and cause round holes to appear within a weld bead. This condition is known as porosity. The main cause of gases getting trapped in the metal is the presence of moisture, rust, grease or paint on the edges of the plate.
To prevent porosity, the first crucial steps is checking gas flow. Each and every application requires different gas flow rates, so welders should select correct flow rate. Checking the welding torch for leaks, checking the shielding gas type, and keeping welding material surface as clean as possible can help to improve efficiency and enhance quality of the weld.
Common Welding Mistakes – Improper Striking of the Arc
An experienced and expert welder is able to strike and establish the correct arc efficiently and quickly. But striking an arc exactly can be extremely difficult for newbie welders. A wrong arc strike will cause damage to the metal to be welded. So, it is crucial to establish the arc correctly.
For this, welders, must hold the striking rod at correct angle and strike precisely at the point where the weld is to begin. Welders can achieve this by standing in a comfortable position and remaining as stable as possible. This will ensure that exact arc is established and that there is no damage to the work piece.
Common Welding Mistakes – Spatter
During gas metal arc welding (GMAW) procedure, sparks and spatter fly all over the place. Scatters are droplets of molten metal that are scattered around during the welding process. Although, it is impossible to completely eliminate spatter in GMAW, its quantity can definitely be reduced.
Incorrect settings of parameters like current and voltage, steep work angle, and bad quality consumables cause spatters. Accurate setting of parameters, the reduction of the welding current and arc length, and checking shielding gas type and flow rate can help in reducing spatters.
Common Welding Mistakes - Preheating and Interpass Temperature Control
Preheating and interpass temperature controls are important parameters in welding. Preheating involves heating the work piece to a specific temperature. Preheating a work piece to precise temperature slows down the cooling rate and reduces the potential for cracking. Improper preheating will affect the first weld pass. Improper interpass temperature will affect all subsequent weld passes. Therefore, precise control of both preheat and interpass temperatures is imperative. Welders must adhere to prescribed temperature values for specific work pieces. They should ensure that welding procedure begins while the material is at or above the preheat temperature. This will prevent cracking of the material.
The above are some common welding mistakes which can be avoided. But please remember that adhering to best welding practices and having the best welding equipment can help you to avoid and prevent these costly mistakes, improve productivity and efficiency, and save time and money for everyone involved.