What should be monitored to prevent burn through during welds on in-service equipment?

To prevent burn-through during welding on in-service equipment, monitoring heat input is crucial. Heat input is defined as the amount of heat energy applied to fuse the base metal effectively during the welding process. If the heat input is too high, it can lead to excessive melting of the base material, resulting in burn-through—a condition where the molten weld pool penetrates all the way through the material, creating holes or excessive thinning.

Controlling heat input involves understanding and adjusting welding parameters such as voltage, amperage, travel speed, and filler material. Ensuring that these parameters are set correctly helps maintain the appropriate temperature in the weld zone while avoiding damaging heat buildup that could compromise the integrity of both the weld and the base metal.

Although other factors like weld speed, base metal thickness, and weld joint design can influence the welding process and affect the risk of burn-through to some degree, they do not directly address the core issue of managing the amount of heat being applied to the material during the weld. Proper heat input control is the key to preventing burn-through, ensuring that the weld can be made soundly while preserving the base metal's integrity.