Roll configuration for an air press of a papermaking machine

An air press for use in a paper machine for removing liquid from a fiber web, said air press comprising a plurality of rolls, each said roll having a peripheral surface, said plurality of rolls including at least one pair of adjacent rolls defining a nip therebetween, each said roll in said at least one roll pair including longitudinally opposite replaceable ends, said replaceable ends defining a portion of said peripheral surface with said nip therebetween, each said roll in said roll pair including opposite longitudinal ends with a peripheral annular groove at each end, each said groove defining a shoulder and an axial face, each said replaceable end being positioned in a corresponding said groove adjacent said shoulder and said axial face.

A paper machine for making a fiber web, said paper machine comprising:

• a plurality of conveyor rolls for carrying the fiber web;
• and
• an air press for pressing the fiber web, said air press comprising a plurality of rolls, each said roll having a peripheral surface, said plurality of rolls including at least one pair of adjacent rolls defining a nip therebetween, each said roll in said at least one roll pair including longitudinally opposite replaceable ends, said replaceable ends defining a portion of said peripheral surface with said nip therebetween, each said roll in said at least one roll pair including a middle portion extending between said replaceable ends, said replaceable ends being configured to provide a higher nip pressure than said middle portion, said nip pressure being effected through at least one of a material selection and geometry of said replaceable ends.

A paper machine for making a fiber web, said paper machine comprising:

• a plurality of conveyor rolls for carrying the fiber web;
• and
• an air press for pressing the fiber web, said air press comprising a plurality of rolls, each said roll having a peripheral surface, said plurality of rolls including at least one pair of adjacent rolls defining a nip therebetween, each said roll in said at least one roll pair including longitudinally opposite replaceable ends, said replaceable ends defining a portion of said peripheral surface with said nip therebetween, each said roll in said roll pair including opposite longitudinal ends with a peripheral annular groove at each end, each said groove defining a shoulder and an axial face, each said replaceable end being positioned in a corresponding said groove adjacent said shoulder and said axial face.