What does PJP stand for in groove weld terminology?

• A. Primary Joint Penetration
• B. Partial Joint Penetration
• C. Permanent Joint Penetration
• D. Progressive Joint Penetration

Answer: (B)

Partial Joint Penetration describes a groove weld where the weld does not reach the far side of the joint. In this case, the weld metal fuses with the base metal to a depth that is less than the full thickness of the joint, so the opposite face remains unfused or only partially fused. This is common when the members are thin or when the design allows for reduced heat input and distortion, since it avoids building up weld metal all the way through the thickness. It contrasts with full (or complete) penetration, where the weld fuses through to the far side, providing maximum joint strength for that throat. The term used in groove weld terminology for this condition is Partial Joint Penetration, which is why that option is the correct one.