Bellows plungers having one or more helically extending features, pumps including such bellows plungers, and related methods

Abstract

A pump system includes at least one pressure chamber at least partially defined by a helical bellows plunger comprised of a tubular body, a closed front portion, an open rear portion, and at least one contour extending continuously as a helix, longitudinally from proximate the front portion to proximate the rear portion. Methods for forming a helical bellows plunger include molding the helical bellows plunger using a mold core comprising a helically extending exterior contour and a cooperatively associated mold cavity comprising a helically extending interior contour of substantially a same pitch and configured to align with the helically extending exterior contour of the mold core, introducing a molding material therebetween, curing the molding material, and unscrewing the cured molding material from the mold core. Various configurations of helical bellows plungers are also disclosed.