What is the primary aim of surface preparation of parts before welding?

The primary aim of surface preparation of parts before welding is to ensure proper adhesion and integrity of the joint. Having clean and properly prepared surfaces is essential because contaminants such as oil, rust, paint, or dirt can interfere with the welding process. Contaminated surfaces may lead to defects in the weld, such as porosity or lack of fusion, which could compromise the strength and durability of the welded joint.

By preparing the surfaces through methods such as cleaning, grinding, or sandblasting, welders can create an environment where the metals can bond effectively, thus achieving a strong and reliable connection. This proper adhesion is vital for maintaining the integrity of the structure being welded, particularly in applications where safety and performance are critical.