MACHINE WITH REDUCED CYLINDER FRICTION

A machine (101) having one or more cylinders (103), each cylinder (103) having an inner surface (105) configured to engage at least a portion of a circumferential surface of a piston ring (107) of a piston (109), the inner surface (105) having a plurality of recesses (129) indented into the inner surface (105), each recess (129) having a circumferential dimension (145), the recesses (129) being arranged into a row (151) that extends circumferentially around the inner surface (105), the recesses (129) of the row (151) having a circumferential spacing (150) between an adjacent recess (129), wherein the ratio of the dimension of the recess (129) in a circumferential direction to the dimension of the circumferential spacing is approximately 2:1.