Filters, methods of making a filter, and filtering methods

摘要

A filter includes a cylindrical filter element having a longitudinal axis, first and second end surfaces, and a plurality of longitudinal pleats. Each of the pleats includes a leg which has a height greater than (D-d)/2, where d is the inner diameter and D is the outer diameter of the filter element. Adjacent legs of the pleats are in contact. First and second end elements are sealed to first and second ends of the filter element, and a retainer is disposed around the filter element. <IMAGE>