A twisted helically-shaped member (15) in the form of a twisted tie, twisted fastener, twisted wire or twisted rod; said twisted helically-shaped member (15) having an axial core (12) and a plurality of helical threads (13H) extending along the axial core (12); and wherein a variation in lead measurements along the length of at least one helical thread (13H), is less than a variation in pitch measurements along the lengths of the helical threads (13H); wherein the axial core (12) has a transverse cross-sectional area comprising two-fifths or less of the transverse circumscribed cross-sectional area of the helical threads (13H).

A twisted helically-shaped member (15) in the form of a twisted tie, twisted fastener, twisted wire or twisted rod; said twisted helically-shaped member (15) having an axial core (12) and a plurality of helical threads (13H) extending along the axial core (12); and wherein a variation in lead measurements along the length of at least one helical thread (13H), is less than a variation in pitch measurements along the lengths of the helical threads (13H); wherein the axial core (12) has a transverse cross-sectional area comprising two-fifths or less of the transverse circumscribed cross-sectional area of the helical threads (13H).

A twisted helically-shaped member (15) in the form of a twisted tie, twisted fastener, twisted wire or twisted rod; said twisted helically-shaped member (15) having an axial core (12) and a plurality of helical threads (13H) extending along the axial core (12); and wherein a variation in lead measurements along the length of at least one helical thread (13H), is less than a variation in pitch measurements along the lengths of the helical threads (13H); wherein the axial core (12) has a transverse cross-sectional area comprising two-fifths or less of the transverse circumscribed cross-sectional area of the helical threads (13H).

Method and means of manufacturing ties, fasteners and rods (15) having a plurality of longitudinal threads by forcing a coil of roll-profiled feed-wire made of steel (11) through a twisting-die made of plastic (1). Also described is: a twisting-die made of plastic (1) that is suitable for twisting profiled feed-wire (11) made of steel; a method of forming a plastic twisting die (1) using an driven tap (31) in the form of a twisted rod (15); and a helically-shaped member (15) having lead measurements (X) along the length of the helical thread that vary less than pitch measurements (Y) along the lengths of the helical threads.

Method and means of manufacturing ties, fasteners and rods (15) having a plurality of longitudinal threads by forcing a coil of roll-profiled feed-wire made of steel (11) through a twisting-die made of plastic (1). Also described is: a twisting-die made of plastic (1) that is suitable for twisting profiled feed-wire (11) made of steel; a method of forming a plastic twisting die (1) using an driven tap (31) in the form of a twisted rod (15); and a helically-shaped member (15) having lead measurements (X) along the length of the helical thread that vary less than pitch measurements (Y) along the lengths of the helical threads.

Provided is an electrical dust-collecting filter manufacturing method and an electrical dust-collecting filter. The method includes the steps of: preparing a frame body, a dust-collecting electrode, a discharge electrode, and a discharge frame; assembling the dust-collecting electrode into an assembly hole of the frame body; connecting the discharge frame to the frame body via an insulating member; and arranging the discharge electrode in an axial direction inside the dust-collecting electrode via the discharge frame and fixing the same. The dust-collecting electrode assembling step includes: temporarily elastically deforming the dust-collecting electrode in the radial direction and inserting the same into the assembly hole of the frame body; and pressurizing end parts of both ends of the dust collecting electrode, which protrude out of a plate member when fitted into the assembly hole, in the axial direction such that the end parts are compressed against the surface of the plate member.

Provided is an electrical dust-collecting filter manufacturing method and an electrical dust-collecting filter. The method includes the steps of: preparing a frame body, a dust-collecting electrode, a discharge electrode, and a discharge frame; assembling the dust-collecting electrode into an assembly hole of the frame body; connecting the discharge frame to the frame body via an insulating member; and arranging the discharge electrode in an axial direction inside the dust-collecting electrode via the discharge frame and fixing the same. The dust-collecting electrode assembling step includes: temporarily elastically deforming the dust-collecting electrode in the radial direction and inserting the same into the assembly hole of the frame body; and pressurizing end parts of both ends of the dust collecting electrode, which protrude out of a plate member when fitted into the assembly hole, in the axial direction such that the end parts are compressed against the surface of the plate member.

Provided is a copper alloy fastener element which improves season cracking resistance by a means different from that of increasing a ratio of a phase. The copper alloy fastener element includes a copper-zinc alloy as a base material, the base material having: an apparent zinc content of from 34 to 38%; a dendrite structure; and a phase at a ratio of 10% or less.

Provided is a copper alloy fastener element which improves season cracking resistance by a means different from that of increasing a ratio of a phase. The copper alloy fastener element includes a copper-zinc alloy as a base material, the base material having: an apparent zinc content of from 34 to 38%; a dendrite structure; and a phase at a ratio of 10% or less.

Provided is a copper alloy fastener element which improves season cracking resistance by a means different from that of increasing a ratio of a phase. The copper alloy fastener element includes a copper-zinc alloy as a base material, the base material having: an apparent zinc content of from 34 to 38%; a dendrite structure; and a phase at a ratio of 10% or less.