The purpose of ribs on the outside of a Wayne Sewer Ball is to:

• A. Allow the ball's weight to be closer to the ball's center
• B. Avoid patent infringement that would apply if a non-ribbed ball were used
• C. Cause jet action to aid in the hydraulic flushing of the sewer line
• D. Reinforce the ball

Answer: (C)

Ribs on the outside are there to turn the moving water into jet action that cleans the line. As water flows past the ridges, it is directed into narrow gaps and around the ball, creating high-velocity jets that blast against the pipe walls. Those jets help dislodge debris and enhance hydraulic flushing, making the sewer line cleaner as the ball moves through. The other ideas—adjusting weight distribution, patent concerns, or simply reinforcing the ball—don’t explain the main cleaning effect driven by the ribbed surface.