An indexable drilling tool includes a cutting insert and a body. The body has a cylindrical shape. The body has a chip discharge groove and a tip seat. The chip discharge groove is in an outer circumference of the body. The tip seat is at a distal end of the body. The tip seat where the cutting insert is placeable wherein. Among wall surfaces constituting the chip discharge groove, a wall surface facing in a direction opposite to a rotating direction of the body. The wall surface has a bulging portion at a distal end thereof. The bulging portion protrudes so as to cover a part of a top surface of the cutting insert. A maximum gap between the bulging portion and the top surface of the cutting insert is smaller than a height of a wall constituting the tip seat.

A metal cutting drill insert for a drill tool having a chip disruptor provided at a rake face. The chip disruptor is further configured with a chamfer at a leading cutting edge region to increase cutting resistance and facilitate chip breakage.

A cutting section (11) which is connectable to a drill shaft section via a releasable connecting device. The cutting section includes a first closed tubular element (14) which is in the form of a first hollow cylinder having a first waved, trapezoidal or zigzag-shaped cross-sectional area, a second closed tubular element (15) which is in the form of a second hollow cylinder having a circular ring-shaped cross-sectional area, and one or more drill segments (16) which are connected to the first closed tubular element (14).

A rotary cutting tool includes a tool body including a chip flute portion having a plurality of helical chip flutes separated by lobes. In one aspect, a tunable vibration absorber assembly is disposed within a cavity formed in the chip flute portion. In another aspect, the tunable vibration absorber assembly is disposed within a cavity of a replaceable cutting head. In each aspect, the tunable vibration absorber assembly includes one or more tunable absorber masses, a resilient material between the one or more absorber masses and the cavity, and one or more connecting members for preventing relative angular displacement of the one or more tunable absorber masses. The one or more tunable absorber masses are suspended only by the resilient material, thereby enabling the tunable vibration absorber assembly to be tuned to a desired frequency for suppressing torsional vibration of the rotary cutting tool during a cutting operation.

A cutting head rotatable about a head axis, has a cap portion and a mounting protuberance joined thereto and extending axially rearwardly therefrom. The mounting protuberance has a plurality of circumferentially spaced apart torque portions axially offset from a plurality of circumferentially spaced apart clamping portions. The clamping portions have clamping surfaces circumscribed by an imaginary clamping circle with a clamping diameter. The torque portions have torque protrusions and torque cut-outs, each torque protrusion having a torque transmission surface at least partially located outside an imaginary clamping cylinder defined by the imaginary clamping circle, and each torque cut-out having a recessed surface located inside the imaginary clamping cylinder. The cutting head is releasably secured to a head receiving pocket of a tool shank, with each clamping surface contacting a corresponding abutment surface of the pocket, and each torque transmission surface contacting a corresponding drive surface of the pocket.

The present invention relates to a tool bit replaceable rotary cutting tool and a rotary cutting method and a tool bit mounting method thereof and belongs to the field of hole machining in the machining industry. At present, a twist drill for drilling is of an integrated structure, and when service life of a tool bit is exhausted, the whole drill is required to be replaced, so that cost is relatively high. For a tool bit replaceable drilling tool, in a drilling process, radial and axial acting forces on a tool bit are relatively strong and thus may cause the conditions of imprecise drilling caused by radial displacement of the tool bit at a joint and the like, a replaceable structure of the tool bit makes the joint of the tool bit of the drilling tool relatively weak and a design of a chip groove makes a substrate of the drilling tool weaker. According to the tool bit replaceable rotary cutting tool of the present invention, a tool bit is detachably connected with a tool bar, and V-shaped positioning surfaces are adopted for a joint of the tool bit and the tool bar, so that a good tool bit positioning and fixation effect is achieved, and the tool bit is unlikely to deviate; a design with different helical angles is adopted for a chip groove, so that strength of the tool bar is strengthened; due to design of cooling guide grooves, a cooling effect is improved; and the tool bit is easy to mount and dismount.

A drill according to a non-limiting aspect may have a body, a cutting edge, a rake face, and a groove. The cutting edge may have a curved chisel edge, a pair of first cutting edges, and a pair of second cutting edges. The second cutting edge may have a first portion extending from the chisel edge and a second portion extending from the first portion toward the first cutting edge. The rake face may have a first region extending from the first portion and a second region extending from the second portion. A first rake angle of the first region may be zero or a negative value. A second rake angle of the second region may be a negative value. An absolute value of the second rake angle may be greater than an absolute value of the first rake angle.

A cutting insert is provided, comprising a top surface, a bottom surface, a plurality of side surfaces spanning therebetween, and a cutting edge formed at an intersection of the side surface and a forwardly-disposed portion of the top the surface. It further comprises a cooling cavity projecting into the insert, a top end thereof being disposed further forwardly than an open bottom end thereof. The cooling cavity defines at least one molding axis such that a solid element having the shape of the cooling cavity and completely inserted therein may be retracted intact therefrom along a linear path parallel to the molding axis. A circumscribing portion is formed on the side surfaces encircling the cutting insert. The circumscribing portion is formed parallel to the molding axis and has a non-zero height along its entire extent. The cutting insert does not extend beyond the circumscribing portion.

A drilling insert has a central portion with a central axis, and three circumferentially spaced tip portions. Each tip portion has a first axis and two diverging first cutting edges with radially outermost cutting points defining a first circle lying on a tip plane perpendicular to the first axis and having a first cutting diameter. In a view along one of the first axes, a second circle having a second diameter circumscribes the drilling insert, and the first cutting diameter is at least sixty percent of the second diameter. A cutting tool rotatable about a tool axis with a tool cutting diameter includes the drilling insert, and a second cutting insert having a second cutting edge. One of the tip portions is operative having its first axis coaxial to the tool axis, and the second cutting edge extends radially outward of the first cutting diameter.

Drilling tool systems including a drilling body and a drilling inserts are disclosed. The drilling inserts include four indexable cutting edges. The four cutting edges may each comprise a plurality of cutting edge segments and a wiper edge. The plurality of cutting edge segments and the wiper edge are provided at distinct angles to provide effective chip breaking and a stronger cutting edge at the drilling insert corners. Furthermore, the side surfaces of the drilling inserts allow the drilling insert to be more stably supported in a pocket of the drilling body. The drilling inserts may be used in a peripheral pocket of a drilling body.