The O.Berk Company presents Packaging Crash Course Series - Closures 101
Common container and closure dimension specifications were established to ensure a perfect fit and successful packaging. A specific letter represents each finish dimension: The letter “I” is used for the inside opening diameter of the finish, “E” is the outside finish wall diameter, “T” is the thread diameter, and “H” is the top of the finish, or sealing surface, to the top of the bead. On beadless designs–those designs that do not have a defined ring at the bottom of the finish– this dimension is measured from the sealing surface to the bottle shoulder.
Closure finish dimension letters correspond to the related bottle finish dimensions.
If the bottle’s “T” or “E” dimension is too large, or, if the closure’s “T” or “E” dimension is too small, it can potentially lead to torque issues.
Conversely, if the bottle’s “T” or “E” dimension is too small, or the closure’s “T” or “E” dimension is too large, the threads will not engage the full thread land area. This will cause torque retention problems.
If the bottle’s “H” dimension is too short, the cap will bottom out at the bottle’s neck, bead, or shoulder, before a tight seal can be established at the closure land.
If the bottle’s “H” dimension is too tall, the closure skirt may be too high above the bottle bead or shoulder.
Closures are identified by their inside diameter measured in millimeters, followed by a manufacturer-designated number. Click here to see our video how to measure bottle neck or caps.
For more information, contact O.Berk Company today.