What condition necessitates the requirement of a PQR for SAW?

A Procedure Qualification Record (PQR) is necessary to substantiate the effectiveness of a welding procedure under specific conditions. In the context of Submerged Arc Welding (SAW), the correct choice relates to significant changes in variables that could impact the quality of the weld.

When utilizing a different filler metal, a PQR is essential because different filler metals can have varied properties that influence the mechanical characteristics, corrosion resistance, and overall performance of the weld. Each filler metal must be qualified to ensure that it meets the required standards for strength and durability when applied to a particular base material.

Changes in the welding method also mandate a PQR as different techniques can alter the heat input, cooling rates, and fusion characteristics of the weld. Similarly, modifications in wire feed speed could directly impact the deposition rate and bead formation, which would further require testing to ensure quality and compliance with code.

While an increase in electrode angle could affect the weld, it does not independently warrant a new PQR, as the core aspects of the welding process remain unchanged. Therefore, the condition necessitating a PQR revolves around the use of different filler metals, ensuring that each combination is documented and validated for safety and structural integrity in welding applications.