Redesign of Plastic Bottle Closure to Eliminate Failure

Dr. Duane Priddy, Plastic Expert Group

The client manufactures plastic bottles for chemical solutions. At the end of the threads is a tab which produces a clicking sound when the screw cap was fully seated. Occasionally a tab would break off the bottle. Our experts evaluated the current design and performed computer modeling using finite element analysis (FEA) to redesign the bottle and eliminate the failures.

  Figure 1.  Photographs of the bottle with the tab (left) and with tab missing after breakage (right).

Figure 1. Photographs of the bottle with the tab (left) and with tab missing after breakage (right).