Abstract:
There is provided an austenitic stainless steel pipe excellent in steam oxidation resistance. The austenitic stainless steel pipe excellent in steam oxidation resistance contains, by mass percent, 14 to 28% of Cr and 6 to 30% of Ni, and is configured so that a region satisfying the following Formula exists in a metal structure at a depth of 5 to 20 μm from the inner surface of the steel pipe: (α/β)×δ/ε×100≧0.3 where the meanings of symbols in the above Formula are as follows: α: sum total of the number of pixels of digital image in region in which orientation difference of adjacent crystals detected by electron backscattering pattern is 5 to 50 degrees β: the number of total pixels of digital image in region of measurement using electron backscattering pattern ε: analysis pitch width of electron backscattering pattern (μm) δ: grain boundary width (μm).
Abstract:
The process includes: definition of the final hollow part in its internal portion after forging with deformation of solid or thinned-down sections; modelling of the solid or thinned-down sections; formation of the thinned-down sections by recyclable single-material cores positioned at places requiring zones with a thinned-down section, and modelling of the cores; after modelling, definition of the semi-finished product and of the cores in their initial forms having a different configuration from the forged cores; after casting of metal around the cores, in the prior initial form, striking of the semi-finished product with its cores resulting in the part and its cores being deformed from their initial shapes to their final shapes; fettling of the burrs; and removal of the cores.
Abstract:
The process comprises: definition of the final hollow part in its internal portion after forging with deformation of solid or thinned-down sections; modelling of the solid or thinned-down sections; formation of the thinned-down sections by recyclable single-material cores positioned at places requiring zones with a thinned-down section, and modelling of the cores; after modelling, definition of the semi-finished product and of the cores in their initial forms having a different configuration from the forged cores; after casting of metal around the cores, in the prior initial form, striking of the semi-finished product with its cores resulting in the part and its cores being deformed from their initial shapes to their final shapes; fettling of the burrs; and removal of the cores.
Abstract:
A bicycle is provided having a unitary steering tube-crown member and a unitary crank arm-spindle member. A multistage aluminum 3D forging process is used to form the unitary members. This may allow the fabrication of components with substantially hollow interior areas to reduce weight, reduce part count while maintaining high strength and ductility. The multistage 3D forging process provided also allows the combination of multiple components into a single unitary part.
Abstract:
A bicycle is provided having a unitary steering tube-crown member and a unitary crank arm-spindle member. A multistage aluminum 3D forging process is used to form the unitary members. This may allow the fabrication of components with substantially hollow interior areas to reduce weight, reduce part count while maintaining high strength and ductility. The multistage 3D forging process provided also allows the combination of multiple components into a single unitary part.
Abstract:
A pretensioner is provided, of which the cylinder, including a restriction portion, can be inexpensively formed, the cylinder having the restriction portion for positioning a gas generation unit to be mounted to a cylinder, and a pretensioner manufacturing method for manufacturing such a pretensioner is provided. In the pretensioner, since the cylinder is molded by forging, an inexpensive material compared with a stainless pipe member can be used for the molding. In addition, since the positioning portion can be molded during forging-molding for molding the entire cylinder, cost can be reduced even in this regard.
Abstract:
Cold extrusion procedures for obtaining metal elements such as for example bushings, nuts or other elements with dead or through holes, screws, standard and special shape extruded or pressed products, etc. on a machining center comprising a series of hydraulic presses connected to each other with an automatic movement system. The final drilling or shearing of the elements is advantageously carried out by a dedicated drilling or shearing unit, working at high speed, which can consist of a vertical mechanical press. The use of the plant comprising several hydraulic presses together with the rapid drilling or shearing unit makes it possible to achieve a high level of productivity.