A clamp ring includes a generally arced portion. The generally arced portion has a top half and a bottom half each having a guide channel formed therein, the top half and the bottom half each have an exterior portion and an interior portion defining boundaries of the guide channels. The interior portions together have a partially circular cross section with a number of interior reliefs formed therein and the exterior portions together have a partially circular cross section with a number of exterior reliefs formed therein that is greater than zero and equal to or greater than the number of interior reliefs formed in the interior portions.