The present disclosure relates to a piston for a reciprocating-piston internal combustion engine, comprising a piston head and a piston barrel, wherein the piston head has an encircling ring belt with at least one ring groove for a piston ring and has, in the region of the ring belt, an encircling cooling duct. The cooling duct extends from the ring belt as far as a wall of the piston barrel in order to increase an oil film temperature of the oil film in the cylinder liner between the piston barrel and cylinder and to thereby reduce the piston barrel friction.

A piston for an internal combustion engine includes a piston head and a piston skirt, wherein the piston head has a piston base, a circumferential ring part and, in the region of the ring part, a circumferential closed cooling channel or sealed cavity. An inner side of the piston has two lower surfaces which transform continuously in the region of the piston central axis (M) to form an arched surface. The piston skirt has piston hubs provided with hub bores which are interconnected by means of running surfaces which have inner surfaces facing the inside of the piston. Starting from the free ends of the piston skirt, inside the piston on the pressure side (DS) and/or counter pressure side (GDS), an inner surface of a running surface continuously transforms into a guiding surface for a coolant which transforms continuously on the side thereof into a lower surface.

A piston for an internal combustion engine includes a piston head and a piston skirt, wherein the piston head has a piston base, a circumferential ring part and, in the region of the ring part, a circumferential closed cooling channel or sealed cavity. An inner side of the piston has two lower surfaces which transform continuously in the region of the piston central axis (M) to form an arched surface. The piston skirt has piston hubs provided with hub bores which are interconnected by means of running surfaces which have inner surfaces facing the inside of the piston. Starting from the free ends of the piston skirt, inside the piston on the pressure side (DS) and/or counter pressure side (GDS), an inner surface of a running surface continuously transforms into a guiding surface for a coolant which transforms continuously on the side thereof into a lower surface.

Systems are provided for a piston cooling jet system for cooling a piston of a locomotive engine. In one example, a piston cooling jet system includes a feed body hydraulically coupled to an oil reservoir and a pair of piston cooling tubes extending radially outwards, in opposite directions, from the feed body. The tubes may have showerhead outlet features at one end for uniformly spraying oil onto inlets of a piston oil gallery housed in the piston.

Systems are provided for a piston cooling jet system for cooling a piston of a locomotive engine. In one example, a piston cooling jet system includes a feed body hydraulically coupled to an oil reservoir and a pair of piston cooling tubes extending radially outwards, in opposite directions, from the feed body. The tubes may have showerhead outlet features at one end for uniformly spraying oil onto inlets of a piston oil gallery housed in the piston.

Pistons for opposed-piston engines include an interior annular cooling gallery. The gallery is provided with inlet and drain passageways constructed to shield a jet of liquid coolant entering the gallery, thereby reducing interference between the incoming jet and liquid coolant circulating in the gallery.

Pistons for opposed-piston engines include an interior annular cooling gallery. The gallery is provided with inlet and drain passageways constructed to shield a jet of liquid coolant entering the gallery, thereby reducing interference between the incoming jet and liquid coolant circulating in the gallery.

A piston for an internal combustion engine is provided. The piston includes a piston body including an upper combustion surface, an annular side wall with a ring belt region, and a cooling gallery located within the piston body having a fluid inlet. A piston ring is located in a ring groove around the ring belt region and an alignment pin is secured in a hole in the piston side wall to restrict circumferential displacement of the piston ring. The piston body further includes a boss within the cooling gallery into which the hole and the alignment pin extend. The boss projects into the cooling gallery opposite the fluid inlet and is shaped to provide a flow splitter surface configured to divide cooling fluid flowing through the fluid inlet during use into first and second fluid flows and to direct the first and second fluid flows in opposite directions around the cooling gallery.

A piston for an internal combustion engine is provided. The piston includes a piston body including an upper combustion surface, an annular side wall with a ring belt region, and a cooling gallery located within the piston body having a fluid inlet. A piston ring is located in a ring groove around the ring belt region and an alignment pin is secured in a hole in the piston side wall to restrict circumferential displacement of the piston ring. The piston body further includes a boss within the cooling gallery into which the hole and the alignment pin extend. The boss projects into the cooling gallery opposite the fluid inlet and is shaped to provide a flow splitter surface configured to divide cooling fluid flowing through the fluid inlet during use into first and second fluid flows and to direct the first and second fluid flows in opposite directions around the cooling gallery.

Methods and systems are provided for an oil gallery of a piston. In one example, a system for a piston comprising an internal oil gallery. The internal oil gallery comprises one or more of a funnel shaped inlet, a funnel shaped outlet, and a plurality of tongues extending along a circumference of the internal oil gallery.