Why should welding procedure specifications be formulated before welding?

Why is a welding procedure specification (WPS) necessary before welding?

Answer: Ensuring welding quality relies on five key control elements: people, machine, materials, methods, and environment. People refers to the welder's operating skills and experience; machines refer to the high performance and stability of the welding equipment; materials refer to the high quality of the welding consumables; methods refer to the correct welding procedure specifications and standardized operations; and environment refers to a favorable welding working environment.

The WPS, developed before welding based on welding tests and welding procedure assessments, is a "regulation" and a crucial factor in ensuring welding quality.

Why is the base metal surface treated before welding? Answer: Impurities such as oil (paint), water, and rust on the weld groove and surface can melt into the weld and cause defects such as pores, inclusions, slag, and cracks, posing hazards and potential risks to the weld joint.

What is the melting coefficient of welding wire? Answer: The melting coefficient of welding wire refers to the amount of wire that melts per unit current per unit time (g/Ah). The finer the welding wire, the higher its melting coefficient, and the higher its efficiency.

What are welding process parameters? Answer: The general term for the physical quantities (such as welding current, arc voltage, welding speed, wire energy, etc.) selected to ensure welding quality during welding.