This disc rotor has a hat portion having a cylindrical portion and a sliding plate portion having an insertion hole into which the cylindrical portion is inserted, being connected together with the hat portion in a state in which the cylindrical portion protrudes from the insertion hole. The coupling is achieved by pinching an inner peripheral edge of the sliding plate portion between a first portion and a second portion that are formed in the cylindrical portion. The second portion is formed by plastically deforming an outer peripheral side of the cylindrical portion toward the first portion.

The present application discloses wheel engraving equipment, which includes a lower lifting system, lower flange engraving systems, inner rim engraving systems, a wheel positioning and clamping system, an upper lifting and rotating system, a synchronous clamping and rotating system and the like.

A piston manufacturing device includes a first forming device (42) configured to form an annular groove (61) in a piston (11), and a second forming device (52) configured to press an edge (15) of an opening (14) of the piston (11) toward other end side in an axial direction of the piston (11) and to form a thick section (65) extruded from an inner circumferential surface (12b) arranged between the edge (15) and the groove (61) toward an axial center side of the piston (11), wherein a recessed section (53) is formed at a portion of the second forming device (52) that is arranged to abut the edge (15) so that an inner circumferential side of the edge (15) is plastically deformed toward the other end side in an axial direction of the piston (11).

A piston manufacturing device includes a first forming device (42) configured to form an annular groove (61) in a piston (11), and a second forming device (52) configured to press an edge (15) of an opening (14) of the piston (11) toward other end side in an axial direction of the piston (11) and to form a thick section (65) extruded from an inner circumferential surface (12b) arranged between the edge (15) and the groove (61) toward an axial center side of the piston (11), wherein a recessed section (53) is formed at a portion of the second forming device (52) that is arranged to abut the edge (15) so that an inner circumferential side of the edge (15) is plastically deformed toward the other end side in an axial direction of the piston (11).

The invention relates to a design method of high-temperature nickel-based bolts based on damage tolerance theory, comprising the following steps: S.sub.1: acquiring operating parameters for the design; S.sub.2: selecting a material for bolts; S.sub.3: acquiring mechanical properties of the materials; S.sub.4: determining a pretension stress .sub.p of a single bolt; S.sub.5: determining the service stress .sub.s under the steady state; S.sub.6: determining the number n, the effective cross-section area A and the distribution of bolts; S.sub.7: determining a maximum allowable crack dimension; S.sub.8: calculating the maximum allowable service stress .sub.th using the crack propagation threshold K.sub.th at the design temperature; S.sub.9: comparing the service stress .sub.s and the maximum allowable service stress .sub.th, if .sub.s is smaller than .sub.th, then the bolts are safe in the design life; otherwise, return to step S.sub.4 and reduce the pretension stress .sub.p.

The invention relates to a design method of high-temperature nickel-based bolts based on damage tolerance theory, comprising the following steps: S.sub.1: acquiring operating parameters for the design; S.sub.2: selecting a material for bolts; S.sub.3: acquiring mechanical properties of the materials; S.sub.4: determining a pretension stress .sub.p of a single bolt; S.sub.5: determining the service stress .sub.s under the steady state; S.sub.6: determining the number n, the effective cross-section area A and the distribution of bolts; S.sub.7: determining a maximum allowable crack dimension; S.sub.8: calculating the maximum allowable service stress .sub.th using the crack propagation threshold K.sub.th at the design temperature; S.sub.9: comparing the service stress .sub.s and the maximum allowable service stress .sub.th, if .sub.s is smaller than .sub.th, then the bolts are safe in the design life; otherwise, return to step S.sub.4 and reduce the pretension stress .sub.p.

A tool for forming an annular workpiece, such as a gear, is provided. The tool has a cylindrical inner form member that has a perimeter that is surrounded by the gear. Driver moves axially along a central axis of the inner form member and gear. A plurality of outer form members rest on a support and are slideable with respect to the support. Each outer form member is provided with a tapered surface that corresponds with and engages with a tapered surface of the driver. Axial movement of the driver causes the tapered surfaces to engage, sliding the outer form members radially inwardly toward the gear. The outer form members are provided with surface features that form teeth onto the gear when the driver presses the outer form members against the gear.

The method for the manufacture of a spoke for spoked wheels including a step of forming a head of the spoke at a longitudinal end of the shank thereof by equipment for the plastic deformation of the end of the shank, wherein the plastic deformation is obtained by maintaining the shank in relative rotation to the equipment.

The method for the manufacture of a spoke for spoked wheels including a step of forming a head of the spoke at a longitudinal end of the shank thereof by equipment for the plastic deformation of the end of the shank, wherein the plastic deformation is obtained by maintaining the shank in relative rotation to the equipment.

A piston manufacturing device includes a first forming device (42) configured to form an annular groove (61) in a piston (11), and a second forming device (52) configured to press an edge (15) of an opening (14) of the piston (11) toward other end side in an axial direction of the piston (11) and to form a thick section (65) extruded from an inner circumferential surface (12b) arranged between the edge (15) and the groove (61) toward an axial center side of the piston (11), wherein a recessed section (53) is formed at a portion of the second forming device (52) that is arranged to abut the edge (15) so that an inner circumferential side of the edge (15) is plastically deformed toward the other end side in an axial direction of the piston (11).