A pressure vessel includes: (a) a cylindrical sidewall having a wall thickness, an inside surface, an outside surface, and the cylindrical sidewall extending between a first end and a second end, wherein one of the first end or the second end includes a sidewall edge that forms part of an outwardly opening weld groove; (b) an end cap constructed to engage the cylindrical sidewall edge, the end cap comprising an end cap edge corresponding to the sidewall edge and that, when combined with the sidewall edge, forms the outwardly opening weld groove; (c) a cylindrically extending backer bar located in support of the outwardly opening weld groove formed by the sidewall edge and the end cap edge; and (d) a weld joint formed in the outwardly opening weld groove and holding the cylindrical sidewall to the end cap. A method for welding a pressure vessel sidewall and end cap together is provided.

A method for producing a piston for an internal combustion engine may include arranging a piston upper part and a piston lower part in a friction welding device. The piston upper part may include a piston head with a combustion recess. The piston lower part may include two mutually opposite skirt elements connected to one another via two mutually opposite pin bosses. The method may also include arranging a deflecting device configured to deflect at least one weld bead one of on and in the friction welding device. The method may further include joining the piston upper part and the piston lower part to one another via friction welding.

A remanufactured piston for an internal combustion engine includes a crown and a skirt. A piston body includes a first piston body end within the crown and an opposite second piston body end. The crown further includes an annular crown body having an annular crown body edge. The first piston body end further includes an annular piston body edge. The annular piston body edge and the annular crown body edge form a joint, and a metallurgical bond attaches the annular crown body to the piston body at the joint.

A manufacturing method for a cylinder device which includes a cylinder, a piston, a piston rod, a seal member, and an installing member, the method includes: a welding step for fixing the installing member to the cylinder through electrical resistance welding; a demagnetizing step for demagnetizing at least an opening portion of the cylinder; and an assembling step for assembling the piston, the piston rod, and the seal member in the cylinder through the opening portion.

A method for manufacturing a piston of an internal combustion engine from a piston upper part and a piston lower part may include producing at least the piston lower part as a forged steel part. A partial cross section of a cooling duct may be provided in the piston lower part. A closed supply inlet funnel may be forged within the piston lower part. The closed supply inlet funnel may be bored into the piston lower part from the cooling duct. A borehole may be introduced into the piston lower part obliquely to a piston axis. The piston lower part and the piston upper part may be welded to one another.

There is provided a method for manufacturing a piston for a vehicle engine, including: a piston assembling step of forming a piston assembly by assembling a first piston part, a bonding member and a second piston part, wherein the first piston part has two or more bonding surfaces separated from each other and extended in a circumferential direction, and the second piston part has two or more bonding surfaces separated from each other and extended in the circumferential direction; a piston diffusion brazing step of diffusion brazing the first piston part, the bonding member and the second piston part under an open atmosphere by heating the formed piston assembly; and a piston cooling step of cooling a piston unit formed by diffusion brazing the first piston part, the bonding member and the second piston part. The piston diffusion brazing step is performed in a piston manufacturing device which includes a partially opened heating zone, a heater for providing heat into the heating zone, and a moving unit moved in one direction in the heating zone. In the piston diffusion brazing step, the piston assembly is heated while being moved at a predetermined speed through the heating zone in one direction by the moving unit.

A cylinder head for an internal combustion engine, includes: first and second valves being intake valves or exhaust valves; a first circumferential wall portion defining a first port, the first port being opened and closed by the first valve and communicating with a combustion chamber; and a first overlay welded portion formed on the first circumferential wall portion and serving as a first valve seat on which the first valve is seated.

There is provided a method for manufacturing a piston, including: a piston assembling step of forming a piston assembly by assembling a first piston part, a bonding member and a second piston part, wherein the first piston part has two or more bonding surfaces separate from each other and extending in a circumferential direction, and the second piston part has two or more bonding surfaces separate from each other and extending in the circumferential direction; a piston diffusion brazing step of diffusion brazing the first piston part, the bonding member and the second piston part under an open atmosphere by heating the formed piston assembly; and a piston cooling step of cooling a piston unit formed by diffusion brazing the first piston part, the bonding member and the second piston part. The piston diffusion brazing step is performed in a piston manufacturing device which includes a partially opened heating zone, a heater for providing heat into the heating zone, and a moving unit moved in one direction in the heating zone. In the piston diffusion brazing step, the piston assembly is heated while being moved at a predetermined speed through the heating zone in one direction by the moving unit.

A piston includes an upper member having a crown and a combustion surface extending radially inward from the crown. The upper member includes concentrically oriented first and second upper connecting surfaces integrally formed on the bottom side of the upper member. At least one of the upper connecting surfaces includes a curvilinear and/or multi-arcuate cross-sectional profile. The piston also includes a lower member having a pair of opposing skirts, each skirt defining a bore. The lower member also includes concentrically oriented first and second lower connecting surfaces integrally formed on a top side of the lower member. The lower member is integrally connected to the upper member by friction welding. The curvilinear and/or multi-arcuate profile enables a shortened distance between the top surface of the crown and the bore centerline of the bore. Methods of manufacturing the piston are also disclosed.

A piston for an internal combustion engine is provided. The piston includes a lower part joined to an upper part, for example by friction welding with inertia. The upper part presents a combustion surface and an undercrown surface. The piston also includes a cooling gallery surface provided by the upper part and the lower part. The cooling gallery surface surrounds a volume of space for containing a cooling media. The piston can include serrations in the cooling gallery surface and/or undercrown surface to increase surface area and thus reduce the temperature of the piston. The piston can also include shaped weld curls, instead of or in addition to the serrations, which also increase surface area and reduce the temperature of the piston.