Abstract: An orbital drilling device includes, on the same frame: a motor rotating a cutting tool on itself; a first, interior, eccentric, receiving the motor, mounted so as to be able to rotate; a second, exterior, eccentric, receiving the first eccentric, mounted so as to be able to rotate; a reference body, secured to the frame, receiving the second eccentric, mounted so as to be able to rotate; a first unit for driving the first eccentric; a second unit for driving the second eccentric, simultaneously with the rotation of the first eccentric; and a controller configured to reproduce any path of the cutting tool in the zone by continuous control of the angular offset between the first eccentric and the second eccentric.

Abstract: The end cutting edges formed on the front end face of the tool body includes a first end cutting edge that is connected to the front end of the thread cutting edge, and a second end cutting edge that is connected to the first end cutting edge on the side closer to the axis, and is angled more toward the rear end than the first end cutting edge. The angle formed by an imaginary plane perpendicular to the axis and the first end cutting edge is set to 6° or less. The angle formed by the second end cutting edges and the imaginary plane perpendicular to the axis and is set to be greater than the angle formed by the first end cutting edges and the imaginary plane perpendicular to the axis.

Abstract: A thread forming tool comprises a thread generating region that extends along a helical line with a thread pitch angle and a thread direction of the thread to be formed and has an active profile corresponding to the thread profile of the thread to be formed, wherein the thread generating region has a thread tooth having a thread profile with a front thread tooth profile flank and a rear thread tooth profile flank, has a front flank relieved surface, adjoining the front thread tooth profile flank and has a rear flank relieved surface, adjoining the rear thread tooth profile flank, wherein the front flank relieved surface is isolated relative to a front thread tooth flank envelope, wherein the rear flank relieved surface is displaced relative to a rear transverse plane wherein the helical line is inclined to the rear relative to the rear transverse plane by the thread pitch angle.

Abstract: An apparatus and a method are provided for a heating, ventilation, and air conditioning (HVAC) home air filter to remove airborne molecular contaminants and volatile organic compounds (VOCs) from air within residential spaces. The HVAC home air filter comprises a supportive frame having a shape and size suitable to orient the HVAC home air filter within a residential HVAC system. A filter medium is retained within the supportive frame to remove the airborne molecular contaminants and VOCs from air flowing through the residential HVAC system. The filter medium comprises a combination of media layers configured to exhibit a relatively high filtration efficiency and a low air pressure drop across the filter medium. The supportive frame comprises a plurality of elongate sections and corner sections disposed along perimeter edges of the filter medium to support the filter medium within the residential HVAC system so as direct air through the filter medium.

Abstract: A pipe-tapered-thread machining spiral tap includes a tapered thread portion that is circumferentially divided by flutes into a plurality of lands. Each of at least one of the lands has a cutting edge that extends along a corresponding one of the flutes. The flutes are made of a plurality of spiral flutes that are three, four or five spiral flutes each having a helix angle that is not smaller than 30° and smaller than 50°. A flute width ratio AG/(AG+AL) is 0.3-0.5, where AG represents a central angle which is subtended by each of the flutes and which is defined at a center corresponding to the rotation axis in a cross section that is perpendicular to the rotation axis, and AL represents a central angle which is subtended by each of the lands and which is defined at the center in the cross section.

Abstract: A tool for producing an internal thread in a workpiece pilot hole having a thread major diameter and a thread minor diameter, which tool has a thread-forming section, by which an internal thread profile can be produced in a pilot hole wall. The internal thread profile having the thread major diameter and a thread inner diameter. The tool has a drilling section, by which the thread inner diameter of the internal thread profile can be expanded to the thread minor diameter by machining. At least one, in particular exactly one chip groove is associated with the drilling section of the tool, by which chip groove the chips produced as the thread inner diameter is expanded to the thread minor diameter can be transported away.

Abstract: In some aspects of the invention, tool components for processing of plate-like workpieces, the tool component include an end face adjoined by a tool region provided for regrinding, the tool region being configured to undergo regrinding as a result of wear; and at least one identification mark located on the tool component to indicate the amount of shortening of the tool region as a result of regrinding.

Abstract: This invention relates to a screw tap which is rotatable about a rotational axis and has a number of thread-cutting teeth, which respectively have a radially outer tip cutter and are disposed mutually offset, with a predefined thread pitch, in an arrangement running spirally or helically around the rotational axis. In a lead region adjoining one end of the screw tap axially to the rotational axis, the maximum radial distance of the tip cutters of the thread-cutting teeth from the rotational axis increases with increasing axial distance of the tip cutters from one end of the screw tap according to a predefined radial distance function. At least some of the thread-cutting teeth in the lead region, at least in the region of the tip cutters, respectively have a defined cutter rounding between tool face and tool flank.

Abstract: A method for producing a thread can include a) generating a number n?1 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 n?1 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.

Abstract: A cutting tap includes a body having an axial forward end and an axial rearward end. The body has a threaded body portion with spiral flutes adjacent the axial forward end, a cylindrical shank portion adjacent the axial rearward end. The threaded body portion includes a chamfered fluted section and a constant diameter section. The threads have a chamfer relief extending radially inward from the cutting edge to a heel of a land. The amount of chamfer relief reaches a maximum value at a point between the cutting edge and the heel, and then becomes smaller between the point of maximum relief and the heel of the land to provide a clearance that reduces the propensity of the tap to chip.

Abstract: Tap and die devices are provided to repair internal and external threads, respectively. The tap and die devices are provided with components that coaxially align the tap and die to the nut or fitting being repaired. The tap and die devices are easily portable, compact tools that can be used in tight places.

Abstract: A screw tap includes a shaft having at least one cutting portion and a drive portion. The drive portion is of a cross-section complimentary to tools adapted to act upon the drive portion. The shaft is provided with a recess extending axially thereof and adapted to receive drive device having a cross-section corresponding to the cross-section of the recess.

Abstract: A tapping device for use with a variety of standard drivers. The tapping device has an elongate body having a first end and a second end. A thread cutting portion is provided toward the first end, an end section for fitting to a drive tool is provided at the second end, and a shank portion is deposed between the cutting portion and the end section. A flared stop is provided on the shank adjacent to the end section. The end section being a hex head which will operated with standard drive tool such as impact wrenches or traditional sockets and wrenches.

Abstract: A spiral tap including: a screw portion provided with a male screw; a primary flute in a helical shape formed to intersect with a screw thread of the male screw; and a secondary flute formed in a tip portion in the primary flute at a helix angle smaller than a helix angle of the primary flute, the secondary flute having a positive or negative helix angle of 0 to 3 degrees, the spiral tap further including a cutting edge being formed on a ridgeline between a side wall surface toward a tap rotation direction out of a pair of side wall surfaces of the secondary flute and an outer circumferential surface of the screw portion and having a rake angle of ?10 to 0 degrees, and the secondary flute having a flute bottom slope of 5 to 15 degrees.

Abstract: Tap and die devices are provided to repair internal and external threads, respectively. The tap and die devices are provided with components that coaxially align the tap and die to the nut or fitting being repaired. The tap and die devices are easily portable, compact tools that can be used in tight places.

Abstract: A slotted inverse tap, compressible for insertion past damaged entry threads in blind holes. (FIG. 1 thru FIG. 5) The tool can be made to smaller sizes than that of prior art. An elongate slot (23) proceeds through a first threaded end (21), then well into a reduced diameter cylindrical body (25). After insertion to the hole bottom, a tabbed shim (28) is inserted to the slot from its side, then pressed down until stopped. The shim (28) enforces mating engagement with undamaged internal threads. A second end of hex and/or squared or other configuration facilitates use of a tap wrench or other tool for rotational extraction. Damaged threads are reformed/re-cut upon rotational withdrawal.

Abstract: A threading tool, such as a tap or die holder, is configured to be driven by a generic wrench. The tool is provided with a wrench-engageable surface, such as a faceted cylindrical surface, or a cylinder with a polyhedral cross-section perpendicular to its axis. A outwardly extending peripheral flange, downward from the wrench-engageable surface, contacts and allows an open-backed wrench to exert downward force on the tool. A inwardly extending peripheral groove, downward from the wrench-engageable surface, allows a wrench to insert a holding device into the profile of the tool to hold the wrench and tool together. The holder may have a collet that activates the holding function by moving along the axis of the holder, but the collet is prevented from rotating about the axis of the holder. The collet may have a wrench-engageable surface. A collar, threaded to the holder, moves the collet.

Abstract: A spiral fluted tap is provided which includes a threaded portion having an external thread corresponding to an internal thread to be cut and a cutting edge formed along a spiral flute formed to divide the external thread, and being screwed into a prepared hole that is provided on a workpiece to cut an internal thread by the cutting edge on an inner circumferential surface of the prepared hole with discharging chips toward a shank via the spiral flute, the spiral flute having a stepped portion at a rear end of a chamfer portion or in a portion on a shank side from the rear end of the chamfer portion in the threaded portion, and a flute bottom diameter on a distal end side of the spiral fluted tap from the stepped portion being smaller than a flute bottom diameter on a shank side from the stepped portion.

Abstract: A form tap for tapping an article may include a longitudinal shank having a mounting end opposite a tip, the shank having a shank length, and a thread portion with a plurality of threads for engaging a surface of the article. The thread portion includes a first region, a second region and a third region. The form tap includes a plurality of lobes extending though the first and second regions from the tip to the second region end, the lobes being spaced circumferentially around the shank and lying on a crest circumference. Each lobe may be disposed between respective first and second convex relief portions and each relief portion may be spaced radially inward from the crest circumference. Each lobe has a lobe width, the lobe width at the second region end being greater than the lobe width at the tip. The third region is free of lobes.

Abstract: A cutting tap includes a body having an axial forward end and an axial rearward end. The body has a threaded body portion with spiral flutes adjacent the axial forward end, a cylindrical shank portion adjacent the axial rearward end. The threaded body portion includes a chamfered fluted section and a constant diameter section. The threads have a chamfer relief extending radially inward from the cutting edge to a heel of a land. The amount of chamfer relief reaches a maximum value at a point between the cutting edge and the heel, and then becomes smaller between the point of maximum relief and the heel of the land to provide a clearance that reduces the propensity of the tap to chip.

Abstract: A thread repair tool comprises a support, a removable cutter, and a clamp for holding the cutter in position. The support can be provided with a leg supporting the cutter. The inner surface of the leg and the inner surface of the cutter can be tapered so that moving the cutter away from the head of the support can change the cutting diameter.

Abstract: In FIG. 2, a diameter Dd of drilling edges of a drill is selected smaller than a valley diameter d1 of a male thread of a tap portion, and an inner diameter D1 of a female thread is defined by the valley diameter d1 of the male thread. Therefore, a predetermined radial gap is formed between the male thread 30 formed by the tap portion and the drill. When a tap with the drill is reversely rotated to be pulled out from the female thread after cutting the female thread, the tap released from the restriction may deflectively displace in the diameter direction upon pulling out the male thread of the tap portion from the female thread. However, the drill hardly contacts with the female thread, so that the occurrence of the defective product due to the contact is suppressed.

Abstract: A thread forming tap having a complete thread portion, formed with a predetermined back taper with that decreases rotational torque during tapping work, which reduces load acting on first complete protruding portions, formed at an extreme leading end of the complete thread portion, and thereby suppressing degradation in service life of the tool due to wear.

Abstract: A spark plug orientation method may include forming a spark plug housing by advancing a tool a first distance in a first axial direction into a spark plug bore to create a spark plug seat using a seat forming portion of the tool. The tool may be displaced a second distance in a second axial direction generally opposite the first axial direction to provide a predetermined axial orientation between the thread forming portion of the tool and the spark plug seat. The spark plug bore may be engaged at a first predetermined rotational position and the tool may be displaced in an orbital motion and in the second axial direction at a predetermined rate to form a threading on the spark plug bore providing a starting point of the threading at a second predetermined rotational position proximate the spark plug seat.

Abstract: A method for creating an inner thread in an opening of a body, using a thread cutter, including the following steps: a) the thread cutter having an axial lengthwise cutout adjacent to which there are blades that project radially outwards and that have cutting edges, is inserted into the opening, whereby several cutting edges arranged one after the other in the longitudinal direction are provided on the lengthwise cutout, which are offset with respect to each other in the circumferential direction, and which are pushed into the groove when the thread cutter is being inserted, b) the cutting tool is rotated by a maximum of 360° in order to create the entire inner thread in at least one projection next to the groove, whereby the cutting edges penetrate into the projection one after the other as the thread cutter turns, and c) the thread cutter is moved axially out of the opening.

Abstract: The invention relates to a tool for machining a workpiece, which tool is rotatable about a tool axis, having a tool shank and a tool head, which tool head comprises at least one land, at least one spiral point assigned to the land and at least one flute assigned to the land, wherein the flute has a left-hand helix and the spiral point is skewed to the left, or wherein the flute has a right-hand helix and the spiral point is skewed to the right.

Abstract: A tapping unit (1) includes a protection device (12) for permitting an axial retraction movement of a master screw (4) towards the interior of a casing (2) from a reference position into a first proximal backward position with a first defined penetration stroke during which a first elastic return device (13) constantly returns the master screw (4) to its reference position. The protection device (12) furthermore permits an additional axial retraction movement of the master screw (4) towards the interior of the casing (2) from the proximal backward position into a second proximal backward position with a defined penetration stroke during which the master screw (4) is no longer returned towards the exterior of the casing (2).

Abstract: The present disclosure is directed toward a compound relief tap, and more specifically, to a compound relief tap with domains made of a plurality of consecutive threads where each domain has different properties associated with variable thread parameters and variable geometrical arrangements such a variation of a taper angle and relief angles for different portions of domain threads or between domains. In a first embodiment, all of the threads in a domain have a given geometrical arrangement. In a second embodiment, several of the threads of the domain possess the geometrical arrangement. In a third embodiment, only the thread of the domain possesses the geometrical arrangement. And in a fourth embodiment, alternative threads in the domain possess the geometrical arrangement. What is also contemplated is a variation in geometrical arrangement between successive domains for any of these threaded domains.

Abstract: Tap and die devices are provided to repair internal and external threads, respectively. The tap and die devices are provided with components that coaxially align the tap and die to the nut or fitting being repaired. The tap and die devices are easily portable, compact tools that can be used in tight places.

Abstract: A rotary cutting tool is provided which is less likely to cause chips to get stuck, and which can be manufactured at a low cost. The rotary cutting tool includes a body having a relief surface (6) and a rake face (7) which is connected to the relief surface (6). An oxide film (9) is formed on the rake face (7) by oxidizing the surface of the body, and a hard film (8) is formed on the relief surface (6) and the oxide film (9), The hard film (8) is made of a metal carbide, a metal nitride, a metal carbonitride, or a solid solution thereof.

Abstract: A cutting tap includes a body having an axial forward end and an axial rearward end and a central longitudinal axis. The body has a fluted section at the axial forward end. The fluted section includes a chamfered fluted section extending from the axial forward end of the body and terminating at a first full cutting thread. The chamfered fluted section includes a first cutting thread located a first distance from the axial forward end of the body, and a second cutting thread located a second distance from the axial forward end of the body. The second distance is greater than the first distance. The chamfered fluted section is shaped such that a thickness of a section of material removed by the second cutting thread is smaller than a thickness of a section of material removed by the first cutting thread. A method of making the cutting tap is also disclosed.

Abstract: A helical flute has a constant lead part and a gradually increased lead part. The constant lead part has an axial length ranging from 0.3×LA to 1.2×LA and includes at least entirety of a leading part, so that the cutting performance of a cutting edge at the leading part and shape of chips (curled shape, etc.) are stable. In the constant lead part, because a lead is the smallest and a helix angle is large, a rake angle of the cutting edge is large, so that an excellent cutting quality is obtained and the chips become curled well. Meanwhile, in the gradually increased lead part, because of the lead gradually increased toward a shank, the chips are rapidly discharged toward the shank.

Abstract: A tap is designed so that the pollution of the environment can be prevented and the cleaning can be simplified. The tap includes an intake hole having openings at a screw portion of the tap. Air intake is performed through the intake hole, so that the chips generated by the screw portion in the cutting can be aspirated from the openings forcibly. Because the chips can be discharged without using cutting fluids, pollution of the environment can be prevented. Because the chips can be aspirated from the openings and discharged from the intake hole of the tap, the chips are not scattered on the work piece, and thus a cleaning process of the work piece can be simplified.

Abstract: A method of orbital milling is performed using an orbital end mill, which has a cutting bit designed for orbital end milling. The abstract of the disclosure is submitted herewith as required by 37 C.F.R. §1.72(b). As stated in 37 C.F.R. §1.72(b): A brief abstract of the technical disclosure in the specification must commence on a separate sheet, preferably following the claims, under the heading “Abstract of the Disclosure.” The purpose of the abstract is to enable the Patent and Trademark Office and the public generally to determine quickly from a cursory inspection the nature and gist of the technical disclosure. The abstract shall not be used for interpreting the scope of the claims. Therefore, any statements made relating to the abstract are not intended to limit the claims in any manner and should not be interpreted as limiting the claims in any manner.

Abstract: The invention includes a double helix thread cutting tap with both right-handed and left-handed helical chip removal flutes. The double helix thread cutting tap places a positive rake angle on all sets of thread cutting teeth for optimum performance and minimal cutting pressure.

Abstract: A self-aligning tap is used to produce correctly aligned new threads in an existing smooth bore hole. The design of the tap's shank, flutes, and cutting surfaces is that of commonly used existing taps. The flat end of the tap—the end that enters the existing bore hole—contains a threaded bore. A removable pilot that aligns the tap to the axis of the existing bore consists of a cylindrical body with a diameter slightly smaller than the existing bore hole, and a length no greater than the diameter of the major diameter of the tap. The upper end of the cylindrical pilot—the end that shoulders against the tap—comprises a threaded stem whose thread pitch matches that of the tap end's bore, and whose length is slightly less than the tap end bore's depth.

Abstract: A cutting tool that includes an elongate body that has a forward end and a rearward end. The elongate body has a fluted portion that beginning near and extends in a rearward direction from the forward end. The fluted portion has a flute that defines a cutting edge. The flute presents a concave cutting face wherein the concave cutting face is defined by a first radius. The flute further presents a concave core surface adjacent to the concave cutting face wherein the concave core surface is defined by a second radius. The flute presents a convex heel surface adjacent to the concave core surface wherein the convex heel surface is defined by a fourth radius.

Abstract: A form tap for tapping an article may include a longitudinal shank having a mounting end opposite a tip, the shank having a shank length, and a thread portion may include a plurality of threads for engaging a surface of the article. The thread portion may also include a first region, a second region and a third region. The form tap may also include a plurality of lobes extending though the first and second regions from the tip to the second region end, the lobes being spaced circumferentially around the shank and lying on a crest circumference. Each lobe may be disposed between respective first and second convex relief portions and each relief portion may be spaced radially inward from the crest circumference. Each lobe has a lobe width, the lobe width at the second region end being greater than the lobe width at the tip. The third region is free of lobes.

Abstract: The present disclosure is directed to a dual technology relief tap, and more specifically, to a relief tap where a segment on the threaded portion has a first type of relief and the remainder of the threads have a second type of relief or a concentric thread to limit tilt and loosening and ultimately to prevent overfeed or underfeed. In some embodiments, a neutral, negative, positive, convex, or other type of relief is applied generally to most of the threaded portion with or without concentric threads, and a second type of relief of any type, such as a neutral, a negative, a positive, a convex, or other relief, is applied to some selected threads. In another embodiment, the second type of relief is applied to the first threads after the chamfer or are spaced regularly over the threaded surface.

Abstract: A form tap includes a shank having a shank length and a thread portion that extends along at least a portion of the shank length. The thread portion includes a finishing portion and a chamfer portion. Each of the finishing portion and the chamfer portion include a plurality of threads and each thread has a crest and a root. The plurality of threads of both the finishing portion and the chamfer portion are spaced apart at a constant pitch, such that a crest-to-crest distance between adjacent threads remains constant along the entire thread portion.

Abstract: This invention relates to a screw tap which is rotatable about a rotational axis and has a number of thread-cutting teeth, which respectively have a radially outer tip cutter and are disposed mutually offset, with a predefined thread pitch, in an arrangement running spirally or helically around the rotational axis. In a lead region adjoining one end of the screw tap axially to the rotational axis, the maximum radial distance of the tip cutters of the thread-cutting teeth from the rotational axis increases with increasing axial distance of the tip cutters from one end of the screw tap according to a predefined radial distance function. At least some of the thread-cutting teeth in the lead region, at least in the region of the tip cutters, respectively have a defined cutter rounding between tool face and tool flank.

Abstract: The tap comprises a shank portion and a threaded portion connected to the shank portion. The threaded portion includes a plurality of lands separated by flutes where each of the lands has threads formed thereon. Each of the plurality of lands including a chamfer formed at an end thereof where the chamfer is formed with a cutting edge and a heel edge. The cutting edge is formed with a first positive relief angle and the heel edge is formed with a second positive relief angle.

Abstract: A method and apparatus for forming an internal thread on a base body is disclosed. A threading tool that features in parts at least one section having a thread-forming structure is inserted into an opening in the base body, and then, the entire internal thread is formed in the base body by a maximum rotation of the threading tool of 360°.

Abstract: A cutting tap includes a body having an axial forward end and an axial rearward end and a central longitudinal axis. The body has a fluted section at the axial forward end. The fluted section includes a chamfered fluted section extending from the axial forward end of the body and terminating at a first full cutting thread. The chamfered fluted section includes a first cutting thread located a first distance from the axial forward end of the body, and a second cutting thread located a second distance from the axial forward end of the body. The second distance is greater than the first distance. The chamfered fluted section is shaped such that a thickness of a section of material removed by the second cutting thread is smaller than a thickness of a section of material removed by the first cutting thread. A method of making the cutting tap is also disclosed.

Abstract: A cutting tap that has an elongate tap body with a fluted section at the axial forward end thereof wherein the fluted section includes a chamfered fluted section and a finishing fluted section. Each cutting thread in the chamfered fluted section has a cutting face disposed at a cutting face angle that becomes more negative the more axially rearward the cutting thread is from the axial forward end of the chamfered fluted section. Each cutting thread in the finishing fluted section has a cutting face disposed at a finishing cutting face angle that is essentially equal. The finishing cutting face angle is more negative than the cutting face angle for the cutting thread at the axial rearward termination of the chamfered fluted section.

Abstract: A tool adapted to form and method of forming a tapped hole within a workpiece in a single pass, includes a piercing section operable to punch a pilot hole in and produce a slug attached to the workpiece, and a tapping section operable to form a female thread along the periphery of the hole, and more preferably, an extruding section operable to push workpiece material away from the exterior surface defined thereby, an expanding section operable to expand the diameter of the hole, a sealing section operable to seal the hole during a hydroforming process, and a burnishing section operable to further expand and treat the periphery of the hole prior to tapping.

Abstract: A tool for producing a thread such as an internal thread, can include at least one cutting region having at least one cutting edge and at least one thread-forming region. In general, the cutting region(s) and the thread-forming region(s) are coupled or connected to one another in such a way that they are rotatable or rotate together about a tool axis. In addition, at least one cutting region is at least partly formed on a front-face tool end and/or adjacent to a front-face tool end. Furthermore, a front-face recess that is configured for receiving chips is formed on the front-face tool end.

Abstract: As shown in FIG. 1, a helical flute has a constant lead part and a gradually increased lead part. The constant lead part has an axial length ranging from 0.3xLA to 1.2xLA and includes at least entirety of a leading part, so that the cutting performance of a cutting edge at the leading part and shape of chips (curled shape, etc.) are stable. In the constant lead part, because a lead is the smallest and a helix angle is large, a rake angle of the cutting edge is large, so that an excellent cutting quality is obtained and the chips become curled well. Meanwhile, in the gradually increased lead part, because of the lead gradually increased toward a shank, the chips are rapidly discharged toward the shank. Thus, the excellent cutting performance and the chip discharge performance rendered by the gradually increased lead are highly stabilized by the presence of the constant lead part. In this way, the durability is further improved.

Abstract: A thread cutting tap having a threaded portion for cutting out a thread in a wall of a workpiece opening into which the threaded portion is to be introduced. The threaded portion is provided with at least two cutting edges extending in a circumferential direction of the body. Each cutting edge is an integral peripheral part of a flank portion extending substantially radially from the body. The flank portions define between one another a chip removal flute extending in the longitudinal extension of the body for removal of chips. At least one of the flank portions has a side wall divided into a pair of elongated concave surfaces separated by an elongated ridge constituting a chip-breaking member. The chip removal flutes are at least partly helically shaped.

Abstract: The present disclosure is directed toward a compound relief tap, and more specifically, to a compound relief tap with domains made of a plurality of consecutive threads where each domain has different properties associated with variable thread parameters and variable geometrical arrangements such a variation of a taper angle and relief angles for different portions of domain threads or between domains. In a first embodiment, all of the threads in a domain have a given geometrical arrangement. In a second embodiment, several of the threads of the domain possess the geometrical arrangement. In a third embodiment, only the thread of the domain possesses the geometrical arrangement. And in a fourth embodiment, alternative threads in the domain possess the geometrical arrangement. What is also contemplated is a variation in geometrical arrangement between successive domains for any of these threaded domains.