What does "interpass temperature" refer to in welding?

Interpass temperature refers to the temperature of the weld joint between consecutive pass layers. In welding, when multiple passes are required to build up the weld joint, maintaining the correct interpass temperature is critical for several reasons.

Firstly, if the interpass temperature is too low, it can lead to poor fusion between the layers and inadequate strength in the weld. Conversely, if the temperature is too high, it can result in excessive heat input, leading to issues such as distortion or changes in the mechanical properties of the metal.

Monitoring and controlling the interpass temperature ensures that the weld quality is maintained throughout the entire welding process, contributing to the integrity and performance of the final weldment. Maintaining the proper interpass temperature helps prevent defects such as cracking, which can arise from rapid cooling of each layer or improper bonding between layers.