The problem of achieving great collar lengths with good quality and even when using high-strength metals, in particular high-strength steels, in a simple manner is solved by the disclosed methods and devices. One such method for producing a collar on a workpiece may involve preforming a region of the workpiece to form a material reserve for a collar drawing operation and drawing the workpiece to form a collar such that the drawn workpiece comprises a flange region and a drawn region adjoining the flange region, with the drawn region including a wall region and an adjoining drawn base. At least some material from a region of the material reserve may be used to form the wall region. The method may further involve punching the drawn base such that an opening is made in the drawn base and the wall region is adjoined by a drawn base sub-region, as well as widening the drawn base sub-region.

An all-steel floor slat for a reciprocating conveyor system includes a plurality of fastener openings through the top surface of the slat for connecting the slat to an underlying drive mechanism. The fastener openings are formed with counter-sinks for receiving fastener heads.

A piercing die, a holding body, and a piercing punch are used to form a pressed component having a plate-shaped base portion and a tubular boss portion extending from the base portion. The piercing die has a receiving portion, an outer shape-forming portion, and a die-side cutting edge. The piercing punch has an inner shape-forming portion, a punch-side cutting edge, and a straight portion. In a process of forming a pressed component, the piercing punch is pressed against a preform which is formed from a blank and which has a preliminary boss portion so as to cause part of the preliminary boss portion to flow toward the outer shape-forming portion, and so as to then cut off another part of the preliminary boss portion to form a boss portion.

Examples of tooling fixtures and methods for manufacturing computing devices are described. According to some examples, a computer component may be shaped using successive steps of forging after deep drawing. In some examples, certain components may be assembled to form sub-assemblies of computer components and the sub-assembly may then be machined to drive closer tolerances. According to other examples, a work holding tool is described which may include a first plurality of individually movable pins for supporting a first surface of a work piece, the tool also having a second plurality of individually movable pins for applying a restraining force over a second opposite surface of the work piece to retain the work piece in position while maintaining it in its natural state.

There is provided a hole widening method including a preparing process of preparing a forming tool which has a diameter-increasing portion increasing in diameter from a front end side toward a rear end side and a line-shaped projection formed to protrude outward from a surface of the diameter-increasing portion, and a workpiece in which a pilot hole is formed; and a hole widening process of successively widening the pilot hole by pushing the forming tool into the pilot hole such that the line-shaped projection of the forming tool comes into point contact with a part of a circumferential edge portion of the pilot hole in the workpiece two times or more, and forming a stretched flange.

Provided is a method for manufacturing a caulked assembly that is capable of manufacturing the caulked assembly at a low cost, preventing reduction of the strength of a columnar body caused by a circumferential groove, preventing deformation of the columnar body, and assembling a slimmer columnar body with a plate-like body. A mounting hole 10 for inserting and assembling a columnar body 2 is provided in a metallic plate-like body 1, and a thick portion 11 is formed along an inner circumferential edge of the mounting hole 10. Thereafter, as shown in FIG. 1(a), the columnar body 2 is inserted into the mounting hole 10 of the plate-like body 1 so that the plate-like body 1 is set in an assembly position on an outer circumferential surface of the columnar body 2. Further, the thick portion 11 is compressively pressed from an axial direction of the columnar body so as to be plastically deformed toward the center of the mounting hole 10 to thereby tighten and fix the thick portion 11 to the outer circumferential surface of the columnar body 2.

As a burring processed member able to suppress the formation of fatigue cracks in a burring part, one having a structure satisfying the following relations (1) to (3) is disclosed: 3Ra100 . . . (1), 3.0<h . . . (2), 24+r[TS/(40+0.28Ra)]<h . . . (3), where, Ra is an arithmetic mean roughness (m) of the burring end face, h is a height (mm) from the first surface to the burring end face, r is a radius of curvature (mm) of the curved wall part, and TS is the tensile strength (MPa) of the sheet-shaped part.

In performing burring processing on a sheet-like member, the following processes are performed: a punching process of performing punching processing of the sheet-like member; a hole expansion process of performing hole expansion processing of a punched hole formed by the punching process; a re-punching process of performing punching processing again on a portion surrounding the punched hole expanded by force in the hole expansion process; and a burring process of pushing a portion surrounding a re-punched hole that is a punched hole formed by the re-punching process and forming a vertical wall.

The problem of achieving great collar lengths with good quality and even when using high-strength metals, in particular high-strength steels, in a simple manner is solved by the disclosed methods and devices. One such method for producing a collar on a workpiece may involve preforming a region of the workpiece to form a material reserve for a collar drawing operation and drawing the workpiece to form a collar such that the drawn workpiece comprises a flange region and a drawn region adjoining the flange region, with the drawn region including a wall region and an adjoining drawn base. At least some material from a region of the material reserve may be used to form the wall region. The method may further involve punching the drawn base such that an opening is made in the drawn base and the wall region is adjoined by a drawn base sub-region, as well as widening the drawn base sub-region.

The present disclosure relates to a chair tray and chassis, chassis forming method and chassis mounting structure of the same. The chair chassis comprises a chassis body that is arranged with a mounting hole thereon for mounting a regulating knob. The edge at the position corresponding to the mounting hole of the chassis body is arranged with a flange. The structural strength and the fatigue strength of the chassis can be enhanced effectively by arranging the flange at the position corresponding to the mounting hole of the chassis, which avoids the occurrence of fracture at the perimeter of the mounting hole of the chassis during use or test and thus enables the thickness of the chassis to be reduced below 3 mm, reducing production material to a very large extent and saving production cost while also ensuring that it can pass the back pad fatigue test in the BIFMA standard.