[Problem to be Solved] A thread-rolling flat die for a threaded fastener capable of long life and a thread-rolling method using the thread-rolling flat die for a threaded fastener are provided.

[Means for Solving the Problem] A thread-rolling flat die 1 is provided with a first partial bite surface 15 having an inclination with an angle with respect to a finishing surface 13, and a second partial bite surface 16 formed between the first partial bite surface 15 and the finishing surface 13 and having an inclination with an angle with respect to the finishing surface 13. A crest angle 1 of a processing tooth 31 at a thread-rolling starting point 17 in the first partial bite surface 15 is larger than a crest angle 2 of a processing tooth 31 in the finishing surface 13. Therefore, loads applied to dies 10, 50 can be reduced, and this allows a longer life of the thread-rolling flat die 1.

The present invention relates to a thread former for manufacturing an internal thread in a metal workpiece. The thread former includes a forming section having a common central axis of rotation, wherein the forming section has a plurality of lubrication grooves extending parallel to the axis of rotation. The forming section includes a plurality of ridge sections extending along a circumference of the forming section, the plurality of ridge sections being arranged for forming the internal thread in the metal workpiece, and wherein, in a circumferential direction, each two of the plurality of ridge sections are separated by one of the plurality of lubrication grooves. At least the one of the lubrication grooves, when projected into a projection plane perpendicular to the axis of rotation, is asymmetrical with respect to any radius intersecting a surface of the lubrication groove.

The present invention relates to a thread former for manufacturing an internal thread in a metal workpiece. The thread former includes a forming section having a common central axis of rotation, wherein the forming section has a plurality of lubrication grooves extending parallel to the axis of rotation. The forming section includes a plurality of ridge sections extending along a circumference of the forming section, the plurality of ridge sections being arranged for forming the internal thread in the metal workpiece, and wherein, in a circumferential direction, each two of the plurality of ridge sections are separated by one of the plurality of lubrication grooves. At least the one of the lubrication grooves, when projected into a projection plane perpendicular to the axis of rotation, is asymmetrical with respect to any radius intersecting a surface of the lubrication groove.

The pending invention relates to means for repairing female threads. The claimed thread repairing tool (1) for repairing a female thread (2) being damaged comprises the case (3), the first beam (4), the second beam (5), the forming roller (6) rotatably and movably installed on the first beam (4), the pitch profile means (7) installed on the second beam (5), and the adjusting means for providing reciprocal moving to and apart from each other and fixing the first beam (4) and the second beam (5). The invention provides a universal robust tool for repairing female threads allowing adjustment thereof to a diameter of the thread being repaired while applying substantially rolling of the material the thread is made of but not cutting thereof.

The pending invention relates to means for repairing female threads. The claimed thread repairing tool (1) for repairing a female thread (2) being damaged comprises the case (3), the first beam (4), the second beam (5), the forming roller (6) rotatably and movably installed on the first beam (4), the pitch profile means (7) installed on the second beam (5), and the adjusting means for providing reciprocal moving to and apart from each other and fixing the first beam (4) and the second beam (5). The invention provides a universal robust tool for repairing female threads allowing adjustment thereof to a diameter of the thread being repaired while applying substantially rolling of the material the thread is made of but not cutting thereof.

In one aspect, thread forming taps are described herein. In some embodiments a thread forming tap comprises a shank disposed at a first end adapted to engage a tool holder and an elongated working portion disposed at a second end. The working portion comprises at least one helical thread and a plurality of longitudinally-extending linear grooves. The longitudinally-extending linear grooves intersect the helical thread forming a plurality of lobes, wherein adjacent lobes differ from one another in relief type and/or relief rate.

In one aspect, thread forming taps are described herein. In some embodiments a thread forming tap comprises a shank disposed at a first end adapted to engage a tool holder and an elongated working portion disposed at a second end. The working portion comprises at least one helical thread and a plurality of longitudinally-extending linear grooves. The longitudinally-extending linear grooves intersect the helical thread forming a plurality of lobes, wherein adjacent lobes differ from one another in relief type and/or relief rate.

A method for producing a thread can include a) generating a number n1 of twisted grooves in a wall of the workpiece encircling a thread axis (M) or generating a wall of the workpiece which has a number n1 of twisted grooves and encircles a thread axis, b) respectively inserting a thread generating region of a tool into each of the twisted grooves in a twisted insertion movement, c) generating a thread in each wall sub-region, adjoining the groove(s), of the wall of the workpiece by rotating the tool about the thread axis (M) and with a simultaneous axial feed motion of the tool coaxially with respect to the thread axis with a particular axial feed speed and d) moving each thread generating region of the tool out of the associated groove in a twisted removal movement matched to the twisting of the associated twisted groove.

A method for producing a thread can include a) generating a number n1 of twisted grooves in a wall of the workpiece encircling a thread axis (M) or generating a wall of the workpiece which has a number n1 of twisted grooves and encircles a thread axis, b) respectively inserting a thread generating region of a tool into each of the twisted grooves in a twisted insertion movement, c) generating a thread in each wall sub-region, adjoining the groove(s), of the wall of the workpiece by rotating the tool about the thread axis (M) and with a simultaneous axial feed motion of the tool coaxially with respect to the thread axis with a particular axial feed speed and d) moving each thread generating region of the tool out of the associated groove in a twisted removal movement matched to the twisting of the associated twisted groove.

A thread repair assembly is provided. The thread repair assembly comprises a cutting-nut housing including a first axial end, a second axial end and an internal cutting-nut interface, the first and second axial ends each having an opening. The thread repair assembly further includes a cutting nut at least partially enclosed by the cutting-nut housing and including a plurality of cutting threads configured to engage a threaded element when the assembly is urged in a first axial direction and disengage the threaded element when the thread repair assembly is urged in a second axial direction opposing the first axial direction.