Welding Burn Through
Welding burn through is a common welding defect that occurs when the heat input is too high for the thickness of the metal being welded, causing the metal to melt completely and form a hole or opening in the weld. Burn through can also occur if the welding speed is too slow, or if the welder is using too high of a current or voltage setting.
Burn through can be a serious problem as it weakens the weld and can lead to structural failure. It is most commonly seen in thinner metals, such as sheet metal or thin tubing, but can also occur in thicker materials if the welding parameters are not properly adjusted.
There are several ways to prevent burn through when welding:
Adjust the heat input: The heat input can be controlled by adjusting the current, voltage, and welding speed. Lowering the amperage or voltage, or increasing the welding speed, can help reduce the heat input and prevent burn through.
Use a filler metal: Adding a filler metal can help control the heat input and prevent the metal from melting completely. The filler metal acts as a heat sink, absorbing some of the excess heat and preventing burn through.
Use proper welding techniques: Proper welding techniques, such as keeping the weld pool small and moving quickly, can also help prevent burn through. In addition, using a backer plate or copper backing can help absorb excess heat and prevent burn through in thin materials.
Check the joint design: Joint design can also play a role in burn through. Using a thicker material, changing the joint design, or adding a backing strip can help prevent burn through in difficult-to-weld materials.
In conclusion, welding burn through is a common welding defect that occurs when the heat input is too high for the thickness of the metal being welded. It can be prevented by adjusting the heat input, using a filler metal, using proper welding techniques, and checking the joint design. By taking these steps, welders can avoid burn through and ensure a strong, durable weld.