A power cylinder system for a reciprocating engine includes a piston configured to move within a cylinder of the reciprocating engine. The system also includes a groove extending circumferentially about the piston and configured to support a ring. An axially-facing surface of the groove has circumferential undulations at ambient temperatures that are configured to compensate for distortions to the groove caused by operation of the reciprocating engine.

A piston head for a die-casting machine, in particular a cold chamber type, comprises a front surface for pushing the molten metal and a side wall extending around a head axis, wherein at least one ring seat is provided in said side wall suitable to receive a sealing ring. The bottom of the ring seat is connected to the front surface through holes or connection channels for a metal flow under the sealing ring. The holes or connection channels lead into an annular peripheral portion of said front surface, said annular peripheral portion being inclined with respect to a front plane orthogonal to said head axis so as to be turned towards said head axis.

A piston for an internal combustion engine includes a skirt and a crown coupled to the skirt. The crown is produced in isolation from the skirt using an additive manufacturing process. The piston includes a first air gap between the crown and the skirt. According to an example embodiment, the crown includes a plurality of sections produced in isolation from the skirt. The crown may include a second air gap disposed between two of the plurality of sections.

A multilayer piston insulator may comprise a plurality of axially aligned disks of a disk stack comprising, a first disk, a second disk, and a third disk, wherein the second disk is coupled axially between the first disk and the third disk and comprises a different material than the third disk, and wherein the disk stack is configured to couple to a hydraulic piston.

A piston for a cylinder for an internal combustion engine has a piston bowl surface adapted for facing a combustion chamber of the cylinder, the piston bowl surface being provided with a thermal barrier coating layer, wherein the thermal barrier coating layer is provided on a plurality of circumferentially spaced surface parts of the piston bowl surface. A method for producing a piston for a cylinder for an internal combustion engine includes the steps of providing a piston for a cylinder for an internal combustion engine, the piston having a piston bowl surface adapted for facing a combustion chamber of the cylinder, and providing the piston bowl surface with a thermal barrier coating layer, wherein the step of providing the thermal barrier coating layer is made on a plurality of circumferentially spaced surface parts of the piston bowl surface.

A piston for a cylinder for an internal combustion engine has a piston bowl surface adapted for facing a combustion chamber of the cylinder, the piston bowl surface being provided with a thermal barrier coating layer, wherein the thermal barrier coating layer is provided on a plurality of circumferentially spaced surface parts of the piston bowl surface. A method for producing a piston for a cylinder for an internal combustion engine includes the steps of providing a piston for a cylinder for an internal combustion engine, the piston having a piston bowl surface adapted for facing a combustion chamber of the cylinder, and providing the piston bowl surface with a thermal barrier coating layer, wherein the step of providing the thermal barrier coating layer is made on a plurality of circumferentially spaced surface parts of the piston bowl surface.

A pump follower for use in a container storing a material includes a body configured to be inserted into the container, the body having a material contacting surface configured to contact the material in the container and a peripheral surface substantially perpendicular to the material contacting surface. A groove is defined on the peripheral surface of the body and a sealing element is disposed in the groove and configured to slidably contact the container. The sealing element has a channel defined within, where the sealing element is configured to be compressed when the pump follower is inserted into the container, such that the channel decreases in size. A sealing element for use with a pump follower is also disclosed. The sealing element has a body has an outer surface, a first side, and a second side, and a channel defined within the sealing element body.

A pump follower for use in a container storing a material includes a body configured to be inserted into the container, the body having a material contacting surface configured to contact the material in the container and a peripheral surface substantially perpendicular to the material contacting surface. A groove is defined on the peripheral surface of the body and a sealing element is disposed in the groove and configured to slidably contact the container. The sealing element has a channel defined within, where the sealing element is configured to be compressed when the pump follower is inserted into the container, such that the channel decreases in size. A sealing element for use with a pump follower is also disclosed. The sealing element has a body has an outer surface, a first side, and a second side, and a channel defined within the sealing element body.

Pistons and clutch assemblies including the pistons are disclosed. A clutch assembly may include at least one rotatable clutch plate, a reaction plate arranged to rotate with and apply a force to the at least one rotatable clutch plate, and a spring configured to urge the reaction plate away from the at least one rotatable clutch plate. A piston may be provided including a first segment formed as a plate and defining an internal space between the first segment and a housing and a second bulk segment that occupies at least a portion (e.g., 50% by volume) of the internal space. At least one bearing rolling element may be arranged between the reaction plate and the piston to permit relative rotational motion therebetween. The second bulk segment may be formed of plastic or a plastic composite and may reduce the amount of hydraulic fluid present in the internal space.

A cylinder apparatus for a brake may include: a piston configured to reciprocate in a cylinder body; a rod coaxially coupled to the piston; a stopper disposed in the cylinder body with the rod penetrated and inserted into the stopper; and an elastic member disposed between the piston and the stopper and configured to elastically support the piston in a direction away from the stopper. The piston and the rod may be integrally formed by injection molding.