The presently disclosed technology includes a friction stir welding apparatus comprising a frame, a moving platform and a parallel mechanism composed of three branch mechanisms, wherein a first branch mechanism comprises a first sliding pair, a first revolute pair, a telescopic rod and a first spherical pair connected in sequence. A second branch mechanism and a third branch mechanism both comprise a third sliding pair, a second revolute pair, a third linkage and a second spherical pair connected in sequence. The friction stir welding apparatus has high stiffness, low inertia, high dynamic performance and high accuracy, which can achieve precision welding with high requirements on processing quality and accuracy for jointing annular seams of large-scale rocket fuel storage tank barrels in the aviation field, for example. The presently disclosed technology also includes a corresponding friction stir welding system.

A metal case has a bottom part composed of a metal plate, and a side wall part composed of a metal plate that stands from an outer peripheral edge of the bottom part. A boundary part between the bottom part and the side wall part includes a welding portion formed by welding the both parts together. The welding portion is exposed on a surface of the metal case on a lower side in a standing direction of the side wall part. And, a lower end that is a lower end part of the bottom part in the standing direction of the side wall part is located on the lower side in the standing direction than the welding portion is.

An assembly component for a vacuum chamber, comprising a body and a flange, has a surface configured to press a seal against another mechanical part. The flange is made of an aluminum alloy and the surface is covered with a metal deposit mostly comprising nickel.

A steel strip for an electric-resistance-welded steel pipe or tube having a strength of X70 grade or more and excellent HIC resistance and SSC resistance is provided. A steel strip for an electric-resistance-welded steel pipe or tube has a chemical composition containing, in mass %: C: 0.02% to 0.06%; Si: 0.1% to 0.3%; Mn: 0.8% to 1.3%; P: 0.01% or less; S: 0.001% or less; V: 0.04% to 0.07%; Nb: 0.04% to 0.07%; Ti: 0.01% to 0.04%; Cu: 0.1% to 0.3%; Ni: 0.1% to 0.3%; Ca: 0.001% to 0.005%; Al: 0.01% to 0.07%; and N: 0.007% or less, with a balance being Fe and incidental impurities, contents of C, Nb, V, and Ti satisfying the following Expression (1)

[C]−12([Nb]/92.9+[V]/50.9+[Ti]/47.9)≦0.03%  (1),

wherein a ferrite area ratio is 90% or more.

A metallic tubular member having a closed end member for use in heating, ventilation, and air conditioning (HVAC) systems or refrigeration systems and method of manufacturing are presented. In one instance, the method includes providing a metallic tubular stock member having a first end and a second end, wherein the first end is open and closing the first end of the metallic tubular stock member to form a first closed circular member having an outside diameter D.sub.1; forming a sealing aperture having an outside diameter D.sub.2 through the first closed circular end, wherein D.sub.2 is less than 5 percent of D.sub.1; and applying a heat-based sealing process including a metallic flow into the sealing aperture. Other methods and systems are presented.

A welding system including a welding electrode, a closed-loop cooling device, and a vent. The closed-loop cooling device is configured to cool the welding electrode. The closed-loop cooling device includes a pump and a water line. The vent is located along a path of the water line. The vent is configured to release air trapped within the water line.

The invention relates to a container for holding and storing liquids and viscous materials, in particular cryogenic fluids, comprising a jacket (12), which defines the interior (14) of the container (10) having a chamber (16), said container (10) being constituted of at least two container structures (20, 20′, 20″) and each of said at least two container structures (20, 20′, 20″) being formed as one piece from a blank (32) and having a dome portion (22), a branching portion (24), which is contiguous to the dome portion (22), and two cylinder portions (26, 28; 26′, 28′), which are contiguous to the branching portion (24), and the mutually facing container structures (20, 20; 20′, 20″) which are adjacent to each other being joined together.

A welding system of cylindrical structures which welds a welding end surface of an upper cylindrical structure and that of a lower one in an axial direction thereof, includes: two or more welding apparatuses opposite to the welding end surfaces and disposed at equal arrangement intervals in the circumferential direction thereof; a moving device configured to rotate the upper and lower cylindrical structures relative to the welding apparatuses in a circumferential direction thereof; and a control device configured to control the welding apparatuses and the moving device. The welding apparatus has a filler metal and a heating source therefor, and melts and fuses the filler metal on the welding end surfaces to weld them, and the control device is configured to continuously rotate the upper and lower cylindrical structures an angle of the arrangement interval by the moving device, while welding the welding end surfaces with the welding apparatuses.

A method of manufacturing a driving drum includes: molding a first cylindrical member including first large- and small-diameter parts, a diameter of an outer circumferential surface of the first small-diameter part being smaller than that of the first large-diameter part; molding a second cylindrical member having second large- and small-diameter parts, a diameter of an inner circumferential surface of the second large-diameter part corresponding to the diameter of the outer circumferential surface of the first small-diameter part, a diameter of an inner circumferential surface of the second small-diameter part corresponding to that of the first small-diameter part, and the diameter of the inner circumferential surface of the second small-diameter part being smaller than that of the second large-diameter part; and forming a first cam groove between the first and second small-diameter parts and forming a second cam groove between the first and second large-diameter parts.

A casting mold having at least one cavity for manufacturing at least one cast article, in which at least some areas of a casting surface of the casting mold delimiting the cavity have a surface texture. The surface texture has multiple elementary cells, wherein each elementary cell has a structure that projects and/or is recessed with respect to the casting surface and ends within the applicable elementary cell. In addition, a cast article produced by the casting mold is provided.