Which maintenance practice involves applying a protective wax coating after structural repairs to prevent corrosion?

• A. Before welding
• B. After welding for corrosion protection
• C. During primer application
• D. During painting

Answer: (B)

Protecting exposed metal right after repairs is essential because the welds and heat-affected zones are especially vulnerable to moisture and salt that cause corrosion. Applying a protective wax coating after structural repairs creates a moisture-barrier layer directly over the repaired surfaces, sealing the welds and any crevices so oxidation is slowed or prevented as the metal cools and settles. If wax were applied before welding, it could burn off or contaminate the weld, reducing weld quality and leaving the joint unprotected. Painting or primer application serves a different purpose—preparing and finishing the surface with paints or primers—whereas the wax coating is specifically used as a post-repair protective barrier against corrosion.