Abstract: Provided is a cylinder liner which can reduce the friction of the sliding surface from conventional levels and improve fuel efficiency without increasing oil consumption from conventional levels. When the inner circumferential surface of a cylinder liner or cylinder bore used in an internal combustion engine has a first sliding region, a second sliding region, and a third sliding region, and when respective surface roughness Rvk is from 0.05 ?m to 0.3 ?m, from 0.4 ?m to 1.5 ?m, and from 0.15 ?m to 0.7 ?m, a friction can be reduced while maintaining oil consumption.

Abstract: The present invention addresses the problem of providing a cylinder liner or a cylinder bore, which can reduce not only friction on a sliding surface but also oil consumption. In a piston sliding direction of the cylinder bore, grooves of a second sliding region positioned on the side of crankcase have a higher groove area ratio at a depth of 0.3 ?m than grooves of a first sliding region positioned on the side of combustion chamber, and the groove area ratio is in a specific range, whereby friction and oil consumption can be reduced.

Abstract: The present invention addresses the problem of providing a cylinder liner or a cylinder bore, which can reduce not only friction on a sliding surface but also oil consumption. In a piston sliding direction of the cylinder bore, grooves of a second sliding region positioned on the side of crankcase have a higher groove area ratio at a depth of 0.3 ?m than grooves of a first sliding region positioned on the side of combustion chamber, and the groove area ratio is in a specific range, whereby friction and oil consumption can be reduced.

Abstract: Provided are a method of manufacturing an engine, an engine, and a connected cylinder. The method of manufacturing an engine includes at least a fitting step of fitting a connected cylinder to a hollow portion of a cylinder block main body. The connected cylinder is (1) a first connected cylinder including two or more cylinder liners and a connecting portion configured to connect the two or more cylinder liners to each other or (2) a second connected cylinder including a connected cylinder main body portion having two or more cylinder bores and a coating configured to cover an inner peripheral surface of the connected cylinder main body portion in which the cylinder bores are formed. The cylinder block main body has one end side, another end side, and the hollow portion passing through the cylinder block main body from the one end side to the another end side.

Abstract: To reduce a friction, and to provide an excellent seizing resistance. Provided is a cast iron cylinder liner including an inner peripheral sliding surface made of cast iron, and an internal combustion engine including a cylinder bore including an inner peripheral sliding surface made of cast iron, wherein the inner peripheral sliding surface includes a region satisfying Expression (1) to Expression (3), Rvk/Rk?1.0 ??Expression (1) 0.08 ?m?Rk?0.3 ?m Expression (2) Rk?Rpk>0 Expression (3) [Rk is the core roughness depth based on JIS B0671-2:2002, Rpk is the reduced peak height based on JIS B0671-2:2002, and Rvk is the reduced valley depth based on JIS B0671-2:2002 in Expression (1) to Expression (3)].

Abstract: Provided are a method of manufacturing an engine, an engine, and a connected cylinder. The method of manufacturing an engine includes at least a fitting step of fitting a connected cylinder to a hollow portion of a cylinder block main body. The connected cylinder is (1) a first connected cylinder including two or more cylinder liners and a connecting portion configured to connect the two or more cylinder liners to each other or (2) a second connected cylinder including a connected cylinder main body portion having two or more cylinder bores and a coating configured to cover an inner peripheral surface of the connected cylinder main body portion in which the cylinder bores are formed. The cylinder block main body has one end side, another end side, and the hollow portion passing through the cylinder block main body from the one end side to the another end side.

Abstract: Provided is a cast iron material from which excellent friction characteristics can be obtained. Provided is the cast iron material containing C and Fe as a composition, and further containing Cr as the composition in 1.0 to 3.5% in terms of mass %. The cast iron material is used in a sliding component sliding under an environment of lubricating oil to which an additive containing Mo as a constituent element, such as MoDTC, is added. Cr contained in the cast iron material promotes a decomposition reaction of the additive containing Mo added to the lubricating oil to form a film of molybdenum disulfide, the film having low friction. Thus, the fiction can be reduced.