A helical pier and extension shaft, one end of which is formed with a thickened hexagonally shaped female end coupler using a hot forging process that swedges and compresses the walls of the female coupler into a thickened hexagonal configuration, with subsequent heat treatment to recover and enhance yield and tensile strength to the entire main body section and female end coupler of the helical pier and extension shafts. A corresponding hexagonally shaped male coupler may be milled and inertia friction welded to the opposite end of each extension shaft, or alternatively hot forged and internally upset as an integral homogeneous part of each extension shaft, thereby completing construction of the extension shaft with opposing corresponding male and female hexagonal couplers. The forgoing helical pier has particular benefits in applications requiring deep soil penetration and/or when using a grouted helical pier system.

A shaft for a steering device has a first portion, a second portion, and a third portion that is a shaft integrated with the first portion and the second portion and couples the first portion and the second portion in a first direction. The outer diameter of the third portion is smaller than the length of the second portion in a second direction intersecting with the first direction, and is constant across a direction extending along the first direction. The hardness of the third portion is greater than the hardness of the second portion, and is constant across the direction extending along the first direction.

A shaft for a steering device has a first portion, a second portion, and a third portion that is a shaft integrated with the first portion and the second portion and couples the first portion and the second portion in a first direction. The outer diameter of the third portion is smaller than the length of the second portion in a second direction intersecting with the first direction, and is constant across a direction extending along the first direction. The hardness of the third portion is greater than the hardness of the second portion, and is constant across the direction extending along the first direction.

A tubular shaft for a tubular shaft instrument includes a hollow shaft component, an actuating rod arranged in the hollow shaft component, and functional elements that are attached at the distal ends of the shaft component and/or of the actuating rod. The actuating rod is axially displaceable relative to the hollow shaft component to move the distal sections of the functional elements toward one another, past one another, and/or away from one another. The actuating rod includes at least one bending area in which flexible segments and support segments alternate and in which the actuating rod has significantly less bending resistance than outside the at least one bending area. A friction-reducing layer on the at least one bending area of the actuating rod reduces the friction of the actuating rod on the inside wall of the shaft component.

A tubular shaft for a tubular shaft instrument includes a hollow shaft component, an actuating rod arranged in the hollow shaft component, and functional elements that are attached at the distal ends of the shaft component and/or of the actuating rod. The actuating rod is axially displaceable relative to the hollow shaft component to move the distal sections of the functional elements toward one another, past one another, and/or away from one another. The actuating rod includes at least one bending area in which flexible segments and support segments alternate and in which the actuating rod has significantly less bending resistance than outside the at least one bending area. A friction-reducing layer on the at least one bending area of the actuating rod reduces the friction of the actuating rod on the inside wall of the shaft component.

A drive axle shaft and method for making the same are provided. The drive axle shaft includes an elongate tubular body and a wheel flange. The elongate tubular body has a longitudinal axis and comprises a first end portion and a second end. The second end is configured to be coupled to a side gear in a differential. The wheel flange is disposed at the first end portion and is configured to support a vehicle wheel. The elongate tubular body and the wheel flange are formed as a unitary body without any weld therebetween.

A shaft member for a fluid bearing device includes, on an outer peripheral surface thereof, two bearing surfaces (31 and 32) separated from each other in an axial direction, and a middle relief portion (33) formed between the bearing surfaces (31 and 32) and having a diameter smaller than a diameter of the bearing surfaces. The middle relief portion (33) includes a cylindrical surface portion (331) having a ground surface, and stepped portions (332) arranged on both axial sides of the cylindrical surface portion and having a diameter difference from the cylindrical surface portion.

A shaft member for a fluid bearing device includes, on an outer peripheral surface thereof, two bearing surfaces (31 and 32) separated from each other in an axial direction, and a middle relief portion (33) formed between the bearing surfaces (31 and 32) and having a diameter smaller than a diameter of the bearing surfaces. The middle relief portion (33) includes a cylindrical surface portion (331) having a ground surface, and stepped portions (332) arranged on both axial sides of the cylindrical surface portion and having a diameter difference from the cylindrical surface portion.

A method for automatic pass schedule calculation during forging, in particular radial forging, of stepped shafts made of metal workpieces, in particular steel, in a forging machine, preferably a radial forging machine with at least four forging tools arranged around the circumference of the workpiece, which are set up and adapted for simultaneous forging the workpiece and/or the stepped shaft, includes: entering starting parameters for the forging process, preferably radial forging process, into a pass schedule calculation program; specifying target parameters for the forging process, preferably radial forging process; and calculating, by the pass schedule calculation program, based on these start and target parameters, a pass plan or calculated a forge sequence. A control and/or regulation unit and a forging machine for carrying out the method are disclosed.

In a method for thickening a plastically deformable hollow body wall of a hollow body, with effective radial support of the unthickened hollow body wall on an outer supporting face of an outer mold and with effective radial support of the hollow body wall on an inner supporting face of an inner supporting body, the hollow body is acted on by a compressive force by two application members at application points by moving the application members towards one another in the axial direction with a compressing movement. The application points on the hollow body are distanced from one another in the axial direction. An expansion space of the outer mold is arranged between the application points. Due to the compressing movement of the application members, material of the hollow body wall between the application points is plasticised in the region of the expansion space of the outer mold, and plasticised material of the hollow body wall flows into the expansion space of the outer mold, thus thickening the hollow body wall.