A method for thickening a plastically deformable hollow body wall of a hollow body includes the steps of arranging the hollow body in an outer mold, arranging an inner supporting body inside the hollow body, applying a compressive force to the hollow body wall by means of two application members moving towards one another in an axial direction with a continuous compressing movement, and performing an axial relative movement of the application members performing the continuous compressing movement on the one hand and of the outer mold on the other hand. Due to the compressing movement of the application members, material of the hollow body wall is plasticized and flows into an expansion space of the outer mold, an axial extent of the expansion space increasing due to the axial relative movement of the application members performing the continuous compressing movement and of the outer mold.

A gas generator includes an elongated cylindrical housing main body and a plug which closes an axial end portion of the housing main body. The plug made of a metal includes a substantially columnar body portion, a first flange portion located on a side of a first end surface, and a second flange portion located on a side of a second end surface. An annular groove portion defined by the body portion, the first flange portion, and the second flange portion is located in a circumferential surface of the plug. A metal flow in a portion which appears in a surface layer of the circumferential surface of the plug including a surface of the annular groove portion continuously extends to reach the second end surface from the first end surface along the circumferential surface without discontinuity in the circumferential surface.

A method for controlling the microstructure and texture of tantalum is described. The method includes a first forging step for performing upset forging and come-back forging on a tantalum billet multiple times in different directions, the upset forging performed to press two surfaces of the tantalum billet in order to make the two surfaces close to each other and the come-back forging performed to restore the tantalum billet to a rectangular prism shape; and a second forging step for performing wedge forging and come-back forging on the tantalum billet multiple times in different directions, the wedge forging performed to press two edges located in a diagonal direction of the tantalum billet and parallel to each other in order to make the two edges close to each other, and the come-back forging performed to restore the tantalum billet to the rectangular prism shape.

A method for controlling the microstructure and texture of tantalum is described. The method includes a first forging step for performing upset forging and come-back forging on a tantalum billet multiple times in different directions, the upset forging performed to press two surfaces of the tantalum billet in order to make the two surfaces close to each other and the come-back forging performed to restore the tantalum billet to a rectangular prism shape; and a second forging step for performing wedge forging and come-back forging on the tantalum billet multiple times in different directions, the wedge forging performed to press two edges located in a diagonal direction of the tantalum billet and parallel to each other in order to make the two edges close to each other, and the come-back forging performed to restore the tantalum billet to the rectangular prism shape.

A constructing-and-forging method for preparing homogenized forged pieces comprises: preparing preformed billets: cutting off a plurality of continuous casting billets, milling and smoothing surfaces of the billets to be welded, performing vacuum plasma cleaning operation to the surfaces to be welded, stacking the plurality of billets and sealing around the surfaces in a vacuum chamber by electron beam welding; forge-welding and homogenizing the preformed billets: heating the preformed billets to a certain temperature in a heating furnace and taking the heated preformed billets out of the heating furnace, forging the preformed billets by a hydraulic press, then using three-dimensional forging to disperse the welded surfaces such that composition, structure and inclusion of the interface areas are at the same level as those of the bodies of the billets. Cheap continuous casting billets are stacked and forge welded.

A constructing-and-forging method for preparing homogenized forged pieces comprises: preparing preformed billets: cutting off a plurality of continuous casting billets, milling and smoothing surfaces of the billets to be welded, performing vacuum plasma cleaning operation to the surfaces to be welded, stacking the plurality of billets and sealing around the surfaces in a vacuum chamber by electron beam welding; forge-welding and homogenizing the preformed billets: heating the preformed billets to a certain temperature in a heating furnace and taking the heated preformed billets out of the heating furnace, forging the preformed billets by a hydraulic press, then using three-dimensional forging to disperse the welded surfaces such that composition, structure and inclusion of the interface areas are at the same level as those of the bodies of the billets. Cheap continuous casting billets are stacked and forge welded.

A forging method for a shaft member includes preforming at least one of a plurality of enlarged diameter portions to obtain a semi-finished member, and forming a remainder of the enlarged diameter portions in the semi-finished member using a mold. The mold includes a punch, split dies, and a workpiece receiving member. The forming of the remainder of the enlarged diameter portions includes allowing the semi-finished member having the at least one of the enlarged diameter portions to be placed on the workpiece receiving member, cramping the semi-finished member in its radial direction by closing the split dies, and filling the semi-finished member into forming surfaces of the split dies by the pressure applied by the punch under the state in which the semi-finished member is cramped.

A forging method for a shaft member includes preforming at least one of a plurality of enlarged diameter portions to obtain a semi-finished member, and forming a remainder of the enlarged diameter portions in the semi-finished member using a mold. The mold includes a punch, split dies, and a workpiece receiving member. The forming of the remainder of the enlarged diameter portions includes allowing the semi-finished member having the at least one of the enlarged diameter portions to be placed on the workpiece receiving member, cramping the semi-finished member in its radial direction by closing the split dies, and filling the semi-finished member into forming surfaces of the split dies by the pressure applied by the punch under the state in which the semi-finished member is cramped.

A driver for applying torque to threaded fasteners has a plurality of teeth extending along and projecting outwardly from a longitudinal axis of a body on which the teeth are located. The teeth have a helical twist about the longitudinal axis. Each tooth has an angularly oriented engagement surface which is engageable with similarly angularly oriented surfaces within recesses in the head of a compatible fastener. When the driver engages the recesses torque applied to the driver draws the driver deeper into the recesses as the engagement surfaces react against and slide over the angularly oriented surfaces within the recesses. The torque also causes the fastener to turn and advance or retract depending upon the sense of the torque and the angles of the engagement surfaces and the angles of the surfaces within the recesses. The fastener and its method of manufacture are also disclosed.

A driver for applying torque to threaded fasteners has a plurality of teeth extending along and projecting outwardly from a longitudinal axis of a body on which the teeth are located. The teeth have a helical twist about the longitudinal axis. Each tooth has an angularly oriented engagement surface which is engageable with similarly angularly oriented surfaces within recesses in the head of a compatible fastener. When the driver engages the recesses torque applied to the driver draws the driver deeper into the recesses as the engagement surfaces react against and slide over the angularly oriented surfaces within the recesses. The torque also causes the fastener to turn and advance or retract depending upon the sense of the torque and the angles of the engagement surfaces and the angles of the surfaces within the recesses. The fastener and its method of manufacture are also disclosed.