The present invention provides a thermally sprayed coating that is a thermally sprayed iron-based coating formed on an inner circumferential surface of a cylinder bore of an aluminum or aluminum alloy cylinder block. The thermally sprayed coating has a plastic deformation part on its surface. Thus, pores on the surface of the thermally sprayed coating are reduced, resulting in a reduction in the amount of oil consumption.

An engine includes a cylinder liner and a piston movable within the cylinder liner, a crevice formed between a top land of the piston and the cylinder liner, and an oil entry clearance formed between a top ring of the piston and the cylinder liner. The engine also includes an abnormal combustion inhibitor having an oil recapture surface exposed to the crevice and oriented to limit migration of oil from the crevice toward a combustion chamber in the engine. The abnormal combustion inhibitor includes a groove structure having as a substrate at least one of the cylinder liner or the piston. Related methodology is also disclosed.

A liner for a cylinder of an internal combustion engine can comprise a hollow cylindrical wall or body having an inner surface, an outer surface opposite the inner surface, and open top and bottom ends. The outer surface can be without any sealing grooves in at least a bottom portion thereof. A relatively thin portion of the wall or body can be provided below a thick portion of the wall or body, and may reach the bottom end of the wall or body. An angled transition can define a change in thickness from the thick portion to the thin portion.

A piston guiding element, rock drilling machine and method for supporting a front end portion of a percussion piston of a rock drilling machine. The piston guiding element includes a braking recess at its rear end. The element further includes at least one bearing sleeve, which is provided with two axially successive slide bearing sections. Hydraulic fluid is conveyed between the slide bearing sections via a feed system.

A packing sleeve for a pump fluid end. The packing sleeve comprising a tubular body having a first end, a second end, and a total axial length along a center axis extending from the first end to the second end; the tubular body further comprises a first region that is adjacent to the first end, wherein the first region extends away from the first end a first axial distance and a second region that is adjacent to the second end, wherein the second region extends away from the second end a second axial distance and abuts the first region, wherein the first axial distance and the second axial distance equal the total axial length and wherein the first axial distance comprises about 35-70% of the total axial length.

A packing sleeve for a pump fluid end. The packing sleeve comprising a tubular body having a first end, a second end, and a total axial length along a center axis extending from the first end to the second end; the tubular body further comprises a first region that is adjacent to the first end, wherein the first region extends away from the first end a first axial distance and a second region that is adjacent to the second end, wherein the second region extends away from the second end a second axial distance and abuts the first region, wherein the first axial distance and the second axial distance equal the total axial length and wherein the first axial distance comprises about 35-70% of the total axial length.

A cylinder liner for a cylinder bore of a cylinder of an internal combustion engine. The cylinder liner includes a cylindrical casing having an outer surface and an inner surface, wherein each surface has a respective surface area. The liner includes a liner seat positioned on the outer surface wherein the liner seat engages with the cylinder bore to position the cylindrical casing in the cylinder bore. The liner includes a relief feature positioned on the outer surface either adjacent the liner seat or above a mid-stop wherein the relief feature resists distortion of the cylindrical casing from the cylinder bore. The liner can include a stiffening feature positioned above the relief feature on the outer surface. The relief feature forms a depressed surface on the outer surface and the stiffening feature forms a raised surface on the outer surface of the cylindrical casing.

A sliding mechanism of the present invention includes a cylinder bore having a thermally sprayed iron-based coating and includes a piston with a piston ring covered with a hard coating composed mainly of carbon.

The thermally sprayed coating has diamond abrasive grains.

An area ratio of the diamond abrasive grains to a surface of the thermally sprayed coating is 0.3 to 1.8%, which enables suppressing wear of the piston ring having the hard coating composed mainly of carbon.

A sliding mechanism of the present invention includes a cylinder bore having a thermally sprayed iron-based coating and includes a piston with a piston ring covered with a hard coating composed mainly of carbon.

The thermally sprayed coating has diamond abrasive grains.

An area ratio of the diamond abrasive grains to a surface of the thermally sprayed coating is 0.3 to 1.8%, which enables suppressing wear of the piston ring having the hard coating composed mainly of carbon.

Methods and systems are provided for a bore. In one example, a system includes a bore portion for receiving a reciprocating piston, the bore portion having first and second ends between which the piston travels in an axial direction. The bore portion comprises a plurality of recesses, axially spaced apart, and formed in a piston facing surface of the bore portion at a plurality of axial positions, with at least one recess being provided at each axial position. Widths of the plurality of recesses decrease in the axial direction away from a mid-stroke position toward the first and second ends, and depths of the plurality of recesses increase in the axial direction away from the mid-stroke position toward the first and second ends.