Tuberculation is a corrosion-related condition inside piping. It most directly affects which part of the pipe?

• A. Exterior Surface
• B. Joints
• C. Insulation
• D. Interior Walls

Answer: (D)

Tuberculation is a form of internal corrosion that forms raised lumps on the inside surface of metal pipes. As the pipe material corrodes, corrosion products build up and create tubercles that protrude into the bore. These deposits directly affect the interior walls, narrowing the interior passage and roughening the surface, which impedes flow and can trap sediment. Since the change occurs on the inner surface of the pipe, the exterior surface, joints, or insulation aren’t the primary areas impacted by tuberculation. The interior walls are the correct focus because that’s where the corrosion and resulting flow restriction occur.