JP5289869B2 - Cutting edge exchangeable cutting tool and cutting method - Google Patents

Description

The present invention relates to a blade-replaceable cutting tool in which an insert is detachably mounted on a plurality of insert mounting seats provided on the outer peripheral portion of the tip end of a tool body rotated about an axis, and such a blade-replaceable cutting tool. In particular, the cutting edge is designed to perform rough cutting with high feed by mounting roughing inserts and finishing inserts alternately on multiple insert mounting seats. The replaceable cutting tool is characterized in that even when the lateral feed rate is increased, cutting with a good finished surface can be stably performed.

  Conventionally, it is made of metal using a cutting edge-replaceable cutting tool such as a face mill in which inserts are detachably attached to a plurality of insert mounting seats provided on the outer peripheral portion of the tip end of a tool body rotated about an axis. It has been carried out to cut the work material which has been cut.

  In order to cut the work material face-to-face with such a cutting edge-replaceable cutting tool, conventionally, rough cutting inserts are generally mounted on a plurality of insert mounting seats provided on the outer peripheral portion on the tip side of the tool body. After cutting the above-mentioned work material with the cutting edge exchangeable cutting tool for roughing, rough cutting is performed on the work material, and then the inserts for finishing are attached to the plurality of insert mounting seats provided on the outer peripheral portion on the tip side of the tool body. The front face machining for finishing is performed by using a cutting edge exchangeable cutting tool for finishing.

  However, when using two types of cutting edge-replaceable cutting tools, ie, cutting edge-replaceable cutting tools for rough cutting and finishing blade-replaceable cutting tools, when cutting the workpiece face-to-face, each blade-replaceable cutting tool is used. The cost for preparing the cutting tools is high, and it is necessary to replace these cutting edge-replaceable cutting tools according to each cutting process, and the time required for these cutting processes becomes longer, and the cutting There was a problem that the processing efficiency was very poor.

  For this reason, in recent years, as shown in Patent Documents 1 and 2, a plurality of insert mounting seats in a blade-tip replaceable cutting tool are mounted with rough cutting inserts and finishing inserts, and one blade-tip replaceable cutting tool is used. Proposals have been made for efficient finish cutting.

  Here, in what is shown in Patent Document 1, the bottom blade of the finishing insert is formed in a convex arc shape with a curvature radius R of 50 to 500 mm toward the distal end in the axial direction, and the axial cut is increased. Even in this case, it has been proposed to obtain a good finished surface.

  Moreover, in what is shown by patent document 2, while making the bottom blade in a finishing insert protrude slightly in the axial direction front end rather than the bottom blade of a roughing insert, the outer periphery blade in a finishing insert is used in the roughing insert. It has been proposed to reduce the load applied to the finishing insert by providing it so as to retract more than the feed amount per blade than the outer cutting edge so that the outer cutting edge in the finishing insert does not cut.

  Here, in recent years, there is a demand for efficient cutting by increasing the lateral feed rate in the above-described blade-tip-exchangeable cutting tool.

And in the cutting edge exchange type cutting tool shown in the above-mentioned Patent Documents 1 and 2, when the lateral feed rate is increased, the load applied to the roughing insert and the finishing insert increases. The load applied to the corner blade on the outer peripheral side of the axial tip of the finishing insert becomes very large, chattering occurs during cutting processing, and the finish surface condition deteriorates, and the corner blade in the roughing insert and finishing insert There was a problem that defects occurred.
Japanese Patent Laid-Open No. 2008-1000031 JP-A-9-38819

The present invention is a front cutting process of a work material in a cutting edge-replaceable cutting tool in which inserts are detachably mounted on a plurality of insert mounting seats provided on an outer peripheral portion on a distal end side of a tool body rotated around an axis. The problem is to solve various problems as described above.

  In the present invention, in the cutting edge replaceable cutting tool in which the rough cutting insert and the finishing insert are mounted on the plurality of insert mounting seats so as to perform finishing cutting at a high feed rate, the lateral feed speed thereof Even when cutting at high speed, chatter does not occur and the finished surface condition does not deteriorate, and the corner blade in the roughing insert or finishing insert does not break, It is an object of the present invention to make it possible to stably perform cutting with a good finished surface.

In the cutting edge replaceable cutting tool according to the present invention , in order to solve the above-described problem, a rough cutting insert and a plurality of insert mounting seats provided on the outer peripheral portion on the distal end side of the tool body rotated around the axis are provided. In the cutting edge-exchangeable cutting tool in which the finishing insert and the insert are detachably mounted at equal intervals in the circumferential direction, the corner portion where the roughing bottom blade and the roughing outer peripheral blade in the above roughing insert intersect is rounded. In addition to providing a roughing corner blade, the corner portion where the finishing bottom blade and the finishing outer peripheral blade intersect in the shape of a convex arc toward the tip end in the axial direction of the above finishing insert is rounded. is finishing corner edges provided Te, the axial height of the rough cutting corner edge of the h1 (mm), the length of the radial c1 (mm), the radius The inclination angle with respect to direction θ1 (°), the curvature radius of the finishing end cutting edge became arcuate convex toward the axial tip side of the R (mm), the axial direction in the finishing corner edges of the high H2 (mm), the length in the radial direction is c2 (mm), the inclination angle with respect to the radial direction is θ2 (°), and the feed amount per blade of the finishing insert is fz (mm / blade) ) Satisfies the conditions of h1 ≦ 0.6, h2> h1, 100 ≦ R ≦ 500, θ1 <θ2, and the above c1 and c2 satisfy the condition of (c2-c1)> fz / 2 In addition, the above-mentioned finishing bottom blade protrudes toward the front end side in the axial direction from the rough cutting bottom blade , and the workpiece is subjected to front cutting .
Further, in the cutting method according to the present invention, the roughing insert and the finishing insert are equally spaced in the circumferential direction on the plurality of insert mounting seats provided on the outer peripheral portion on the distal end side of the tool body rotated about the axis. In the cutting method of performing the front face cutting of the work material using the cutting edge-replaceable cutting tool that is alternately detachably mounted at the above, the roughing bottom blade and the roughing outer peripheral blade in the above roughing insert intersect. A corner where the corner portion is rounded to provide a roughing corner blade, and the finishing bottom blade and the finishing outer peripheral blade that are convex toward the tip end in the axial direction of the finishing insert intersect. A corner corner for finishing is provided by chamfering the part, the height in the axial direction of the above-mentioned corner blade for roughing is h1 (mm), and the length in the radial direction is c1 (m ), The angle of inclination with respect to the radial direction is θ1 (°), the radius of curvature of the bottom edge for finishing in the shape of a convex arc toward the tip end side in the axial direction is R (mm), The height in the axial direction is h2 (mm), the length in the radial direction is c2 (mm), the inclination angle with respect to the radial direction is θ2 (°), and the feed amount per blade of the finishing insert is fz. (Mm / blade), the conditions of h1 ≦ 0.6, h2> h1, 100 ≦ R ≦ 500, and θ1 <θ2 are satisfied, and the above c1, c2, and fz are (c2-c1)> By satisfying the condition of fz / 2, the above-mentioned bottom blade for finishing was protruded toward the tip end side in the axial direction from the bottom blade for roughing, and the workpiece was subjected to front cutting.

  Here, in the cutting edge replaceable cutting tool of the present invention, in providing the roughing corner blade, the above-described roughing insert has a height h1 in the axial direction and a length c1 in the radial direction satisfying the above conditions. The inclination angle θ1 of the rough cutting corner blade with respect to the radial direction is preferably in the range of 10 ° to 30 °.

  Further, in the cutting edge replaceable cutting tool of the present invention, it is preferable that the roughing outer peripheral blade in the roughing insert is protruded in a radial direction from the finishing outer peripheral blade, and the roughing outer peripheral blade with respect to the finishing outer peripheral blade is provided. It is preferable to set the protrusion amount E of 0.5 mm or less.

  Further, in the cutting edge replaceable cutting tool of the present invention, as described above, when the finishing bottom blade in the finishing insert is protruded more in the axial direction than the roughing bottom blade in the roughing insert, it is provided on the tool body. In order to detachably mount the finishing insert to the inserted insert mounting seat, an adjustment mechanism is provided to adjust the mounting position of the above-mentioned finishing insert in the axial direction. It is also preferable to adjust the amount of protrusion toward the tip end side in the axial direction.

  In the cutting edge exchangeable cutting tool of the present invention, when performing the finish cutting, the cutting amount in the axial direction is set to be equal to or less than the height h1 in the axial direction of the roughing corner blade in the roughing insert.

  In the cutting edge-replaceable cutting tool of the present invention, when the roughing corner blade is provided by chamfering the corner portion where the roughing bottom blade and the roughing outer peripheral blade intersect in the above roughing insert, this roughing corner blade is provided. Since the axial height h1 is set to 0.6 mm or less, the load applied to the rough cornering blade is reduced and chatter occurs even when cutting with a high lateral feed rate. And the occurrence of defects on the roughing corner blade is prevented.

  Further, in the cutting edge replaceable cutting tool of the present invention, the roughing insert is provided with the roughing corner blade as described above, and the finishing bottom is formed in a convex arc shape toward the axial front end side of the finishing insert. In providing a finishing corner blade by chamfering the corner portion where the cutting edge and the outer peripheral cutting edge intersect, the axial height h1 (mm) and the radial length c1 (mm) of the rough cutting corner blade are provided. ), The axial height h2 (mm) of the finishing corner blade, the radial length c2 (mm), and the feed amount fz (mm / blade) per blade of the finishing insert, In addition to satisfying the conditions of h2> h1 and (c2-c1)> fz / 2, the finishing bottom blade protrudes more in the axial direction than the rough cutting bottom blade. In cutting inserts, the finishing outer peripheral edge and the finishing corner edge are prevented from hitting the work material, and only the finishing bottom edge having a convex arcuate shape toward the tip end in the axial direction cuts the work material. It becomes like this.

  For this reason, in the cutting edge-exchangeable cutting tool of the present invention, even when cutting is performed by increasing the lateral feed rate, no load is applied to the finishing outer peripheral blade or the finishing corner blade. , Chattering and chipping are prevented, and the above finishing bottom blade can cut the finished surface appropriately. Especially, the cutting depth in the axial direction is the corner cutting edge for roughing. If the height in the axial direction is equal to or less than h1, even if the depth of cut is increased, the load applied to the corner blade for roughing or the like is reduced, and appropriate finish cutting can be performed efficiently.

  Also, in this way, in the finishing insert, the finishing outer peripheral edge and the finishing corner blade do not hit the work material, and the load applied to the finishing insert is reduced. It becomes possible to use a high-hardness material having excellent wear characteristics, and this finishing insert can be used stably over a long period of time, and a good finished surface can be obtained.

  Furthermore, in the cutting edge exchangeable cutting tool of the present invention, the curvature radius R of the bottom blade for finishing which is in the shape of a convex arc toward the tip end side in the axial direction is in the range of 100 to 500 mm as described above. The finished surface is prevented from becoming rough as in the case where R is reduced, and the occurrence of chatter due to the large load applied to the bottom blade for finishing as in the case where the radius of curvature R is increased. Can be cut.

  Further, in the cutting edge replaceable cutting tool of the present invention, when the inclination angle θ1 with respect to the radial direction of the rough cutting corner blade is in the range of 10 ° to 30 °, chips for feeding per blade of the rough cutting corner blade are provided. Even when cutting with the lateral feed rate increased as described above, the chips are clogged, chattered, or chipped in the corner blade for roughing. Is further prevented.

  Further, in the cutting edge replaceable cutting tool of the present invention, when the roughing outer peripheral blade protrudes in the radial direction from the finishing outer peripheral blade as described above, the roughing insert or the finishing insert is attached to the insert mounting seat of the tool body. Even when there is a so-called peripheral runout, such as an error in the process, the finishing peripheral blade or the finishing corner blade is prevented from hitting the work material as described above. However, if the protruding amount E of the roughing outer peripheral edge with respect to the finishing outer peripheral edge becomes too large, the effective cutting diameter by the finishing bottom edge of the finishing insert decreases as a result, and appropriate finish cutting cannot be performed. As described above, it is preferable that the protruding amount E of the roughing outer peripheral blade with respect to the finishing outer peripheral blade is 0.5 mm or less.

  Hereinafter, the blade-tip-exchangeable cutting tool according to the embodiment of the present invention will be specifically described with reference to the accompanying drawings. The cutting edge exchangeable cutting tool according to the present invention is not particularly limited to those shown in the following embodiments, and can be implemented with appropriate modifications within a range that does not change the gist thereof.

  In the cutting edge-exchangeable cutting tool in this embodiment, as shown in FIGS. 1 and 2, a required interval in the circumferential direction is provided at the outer peripheral portion on the distal end side of the tool body 10 provided with a mounting hole 11 penetrating in the center portion. A plurality of (four in the example shown in the figure) chip pockets 12 are provided, and an insert mounting seat 13 is provided on the surface of each chip pocket 12 on the rear side in the rotational direction.

  Then, the rough cutting insert 20 having a substantially rectangular plane is mounted on the cartridge 20a, and the finishing insert 30 having a substantially rectangular plane is mounted on the cartridge 30a. In this way, the roughing insert 20 is mounted. The cartridge 20a and the cartridge 30a to which the finishing insert 30 is attached are detachably attached to the insert mounting seat 13 in the tool body 10 and the prepared screws are respectively attached to the cartridges 20a and 30a. 20b and 30b are provided, and the mounting positions of the roughing insert 20 attached to the cartridge 20a and the finishing insert 30 attached to the cartridge 30a are adjusted in the axial direction of the tool body 10 by the adjusting screws 20b and 30b. I have to.

  Here, in each roughing insert 20 mounted on the insert mounting seat 13 of the tool body 10 via the cartridge 20a as described above, as shown in FIG. 3, a roughing bottom blade 21 and a roughing outer peripheral blade 22 are provided. A corner portion intersecting with is rounded off, and a rough cutting corner blade 23 is provided.

  Moreover, in each finishing insert 30 attached to the insert mounting seat 13 of the tool body 10 via the cartridge 30a as described above, as shown in FIG. A corner portion where the finished bottom blade 31 and the finishing outer peripheral blade 32 intersect is rounded, and a finishing corner blade 33 is provided.

In the rough cutting insert 20, the corner portion has a small chamfered corner, the radius c 1 (mm) in the radial direction of the rough cutting corner blade 23 is reduced, and the rough cutting corner blade 23 has The inclination angle θ1 with respect to the radial direction is set to a range of 10 ° to 30 °, and the height h1 (mm) in the axial direction of the corner blade 23 for roughing is set to 0.6 mm or less.

  Further, in the finishing insert 30 described above, the curvature radius R (mm) of the finishing bottom blade 31 that has a convex arc shape toward the tip end in the axial direction is set in a range of 100 to 500 mm, and the corners described above are used. The corner chamfering is made larger than the rough cutting insert 20 described above, the radial length c2 (mm) of the finishing corner blade 33 is increased, and the inclination angle θ2 of the finishing corner blade 33 with respect to the radial direction is increased. Is usually set to about 45 °, and the height h2 (mm) in the axial direction is also larger than the height h1 (mm) in the axial direction of the corner blade 23 for roughing.

  Then, in the state in which the roughing insert 20 and the finishing insert 30 are attached to the insert mounting seat 13 of the tool body 10 as described above, the cutting edge replaceable cutting tool is rotated to finish the roughing insert 20 and finishing. When the roughing insert 20 and the finishing insert 30 are overlapped by guiding the cutting insert 30 to the same position, the finishing bottom blade 31 in the finishing insert 30 is roughened in the roughing insert 20 as shown in FIG. The rough cutting outer peripheral blade 22 in the roughing insert 20 protrudes in the radial direction from the finishing outer peripheral blade 32 in the finishing insert 30 while projecting toward the axial front end side from the bottom cutting edge 31.

  Here, when the amount of projection x that causes the finishing bottom blade 31 in the finishing insert 30 to protrude toward the tip end in the axial direction is larger than the roughing bottom blade 31 in the roughing insert 20, the finishing bottom blade 31 is added to the finishing bottom blade 31 during cutting. Since the load increases and chattering may occur or the bottom blade 31 for finishing may be damaged, it is desirable to set the protrusion amount x to about 0.1 mm.

  Further, as described above, the projection amount E for causing the roughing outer peripheral edge 22 of the roughing insert 20 to protrude more radially than the finishing outer peripheral edge 32 of the finishing insert 30 is preferably 0.5 mm or less. .

  Furthermore, in the cutting edge exchange type cutting tool in this embodiment, the rough cutting corner blade 23 is mounted in the state where the rough cutting insert 20 and the finishing insert 30 are mounted on the insert mounting seat 13 of the tool body 10 as described above. The axial height h1 (mm), the radial length c1 (mm) thereof, the axial height h2 (mm) of the finishing corner blade 33, and the radial length c2 thereof. (Mm) and the feed amount fz (mm / blade) per blade of the finishing insert 30 satisfy the conditions of h2> h1 and (c2-c1)> fz / 2.

  In this case, when cutting by cutting the work material in the rough cutting insert 20 when performing cutting by sending the cutting edge exchangeable cutting tool in this embodiment in the horizontal direction while rotating, the next finishing insert is rotated. Even if 30 is guided to the same rotational position while being fed fz / 2 in the lateral direction, the axial height h2 of the finishing corner blade 33 is higher than the axial height h1 of the roughing insert 20 as described above. And the radial length c2 of the finishing corner blade 33 is larger than the radial length c1 of the roughing corner blade 23 by fz / 2 or more, so that the finishing in the finishing insert 30 is completed. At the positions of the outer peripheral edge 32 and the finishing corner edge 33, the work has already been roughed in the roughing insert 20. And in a state of being cut by the use peripheral cutting edge 22 and the rough cutting corner edge 23. For this reason, the finishing outer peripheral edge 32 and the finishing corner edge 33 do not hit the work material, and the finishing insert 30 has a circular arc convex toward the tip end in the axial direction. Only 31 comes to cut the work material.

  As a result, even when cutting is performed by increasing the feed rate in the lateral direction of the cutting edge exchangeable cutting tool, no load is applied to the finishing outer peripheral edge 32 or the finishing corner edge 33, and chattering is performed. And the occurrence of these defects are prevented, and the finished bottom blade 31 can appropriately cut the finished surface to obtain a good finished surface.

  Next, specific examples of the cutting edge-exchangeable cutting tool according to the present invention will be given. In the cutting edge-exchangeable cutting tool according to the present invention, when cutting is performed by increasing the lateral feed rate Also, it is clarified that a good finished surface can be cut over a long period of time.

Example 1
In the cutting edge-exchangeable cutting tool of Example 1, a tool body having a diameter of 200 mm is used, and as shown in the above-described embodiment, four end portions of the tool body are circumferentially spaced apart from each other at required intervals. A chip pocket was provided, and two rough cutting inserts and finishing inserts each having a substantially quadrangular shape were mounted alternately on the insert mounting seat in each chip pocket via a cartridge.

  Here, in this Example 1, while using as the above-mentioned roughing insert the surface of the insert composed of the fine particle cemented carbide is coated with a TiAlN film by the PVD method, the above-mentioned finishing insert, The surface of the insert composed of cermet was coated with a TiAlN film by the PVD method.

  In Example 1, in the above rough cutting insert, the angle of inclination θ1 with respect to the radial direction at the corner blade for roughing is 26.6 °, the height h1 in the axial direction is 0.5 mm, and the length in the radial direction. c1 was set to 1.0 mm.

  Further, in the above-mentioned finishing insert, the curvature radius R of the finishing bottom blade that has a convex arc shape toward the tip end in the axial direction is 340 mm, the inclination angle θ2 with respect to the radial direction of the finishing corner blade is 45 °, The height h2 in the axial direction was set to 2.2 mm, and the length c2 in the radial direction was set to 2.2 mm.

  Further, the amount of protrusion x that the finishing bottom blade protrudes in the axial direction from the roughing bottom blade is 0.1 mm, and the amount of protrusion E that the roughing outer blade protrudes in the radial direction from the finishing outer blade is 0. 2 mm.

  In the cutting edge-exchangeable cutting tool of Example 1, the cutting speed Vc is 300 m / min, the lateral feed speed Vf is 1900 mm / min, the finishing insert and the cutting material constituted by S15C. Cutting was performed with a feed amount fz per blade in the roughing insert set to 2 mm / blade, an axial cut of 0.3 mm, and a radial cut of 110 mm.

  As a result, in the cutting edge-exchangeable cutting tool of Example 1, even in the cutting process with a cutting length of 100 m, the finishing insert and the roughing insert are not damaged or frayed during cutting. A good finished surface with a roughness Ra of 0.52 μm could be cut.

  In addition, in the cutting edge exchangeable cutting tool in the first embodiment, when the finishing insert is attached to each of the four insert mounting seats and the cutting is performed in the same manner, the above-mentioned finishing insert is not defective in the initial stage. occured.

(Example 2)
Also in the cutting edge exchangeable cutting tool of the second embodiment, similarly to the first embodiment, a tool body having a diameter of 200 mm is used. A chip pocket was provided, and two rough cutting inserts and finishing inserts each having a substantially quadrangular shape were mounted alternately on the insert mounting seat in each chip pocket via a cartridge.

  Here, in this Example 2, as the rough cutting insert, an insert (Rockwell A hardness 91.8) made of a fine cemented carbide is coated with a TiAlCrN film by the PVD method. On the other hand, as the above-described finishing insert, an insert (Rockwell A hardness 92.9) made of a fine cemented carbide was coated with a TiAlCrN film by the PVD method.

  In the second embodiment, in the roughing insert, the angle of inclination θ1 with respect to the radial direction of the roughing corner blade is 26.6 °, the height h1 in the axial direction is 0.5 mm, and the length in the radial direction. c1 was set to 1.0 mm.

  Further, in the above-described finishing insert, the curvature radius R of the finishing bottom blade that is in the shape of a convex arc toward the tip end side in the axial direction is 180 mm, the inclination angle θ2 with respect to the radial direction of the corner blade for finishing is 45 °, The height h2 in the axial direction was set to 2.2 mm, and the length c2 in the radial direction was set to 2.2 mm.

  Further, the amount of protrusion x that the finishing bottom blade protrudes in the axial direction from the roughing bottom blade is 0.1 mm, and the amount of protrusion E that the roughing outer blade protrudes in the radial direction from the finishing outer blade is 0. 3 mm.

  In the cutting edge-exchangeable cutting tool of Example 2, the cutting speed Vc is 180 m / min, the lateral feed speed Vf is 1140 mm / min, the finishing insert Cutting was performed with a feed rate fz per blade in the roughing insert set to 2 mm / tooth, an axial cut of 0.3 mm, and a radial cut of 160 mm.

  As a result, in the cutting edge-replaceable cutting tool of the second embodiment, even in the cutting process with a cutting length of 120 m, the finishing insert and the roughing insert are not damaged, and no cracking occurs during cutting. A good finished surface with a roughness Ra of 1.5 μm could be cut.

It is a schematic bottom view of the blade-tip-exchange-type cutting tool which concerns on one Embodiment of this invention. It is a schematic side view of the blade-tip-exchange-type cutting tool which concerns on the same embodiment. It is the fragmentary explanatory view showing the state where the insert for roughing was attached to the tool body in the cutting edge exchange type cutting tool concerning the embodiment. It is the fragmentary explanatory view showing the state where the finishing insert was attached to the tool body in the cutting edge exchange type cutting tool concerning the embodiment. It is the figure which showed the relationship of the state which has said insert for roughing and finishing insert in the same position in the blade-tip-exchange-type cutting tool which concerns on the same embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Tool body 11 Mounting hole 12 Chip pocket 13 Insert mounting seat 20 Roughing insert 20a Cartridge 20b Preparation screw 21 Roughing bottom blade 22 Roughing outer peripheral blade 23 Roughing corner blade 30 Finishing insert 30a Cartridge 30b Preparation screw 31 For finishing Bottom blade 32 Finishing outer peripheral blade 33 Finishing corner blade h1 Height in the axial direction of the roughing corner blade θ1 Inclination angle of the roughing corner blade with respect to the radial direction c1 Length in the radial direction of the roughing corner blade h2 Finishing corner blade X2 The angle of inclination of the corner blade for finishing with respect to the radial direction c2 The length of the corner blade for finishing in the radial direction E The amount of the outer peripheral blade for roughing projecting more radially than the outer peripheral blade for finishing x Finishing bottom The amount that the blade protrudes toward the tip end in the axial direction from the bottom blade for roughing

Claims (6)

Cutting edge exchange type with multiple insert mounting seats provided on the outer periphery of the tip end of the tool body that rotates about the axis, with inserts for roughing and finishing inserts attached alternately and circumferentially at equal intervals. In the cutting tool, the corner portion where the roughing bottom blade and the roughing outer peripheral blade in the roughing insert intersect is rounded to provide a roughing corner blade, and at the tip end in the axial direction of the finishing insert. The corners where the finishing bottom edge and the finishing outer edge intersect with the convex arcuate shape are chamfered to provide a finishing corner edge, which increases the axial height of the above roughing corner edge. h1 (mm), the length in the radial direction is c1 (mm), the inclination angle with respect to the radial direction is θ1 (°), and the shape is a convex arc shape toward the tip end side in the axial direction. The radius of curvature of the bottom blade for finishing is R (mm), the height in the axial direction of the corner blade for finishing is h2 (mm), the length in the radial direction is c2 (mm), and the inclination angle with respect to the radial direction is When θ2 (°) and the feed amount per blade of the finishing insert are fz (mm / tooth), h1 ≦ 0.6, h2> h1, 100 ≦ R ≦ 500, and θ1 <θ2. The condition is satisfied, and the above c1 and c2 are set so that the condition of (c2-c1)> fz / 2 is satisfied, and the above-mentioned finishing bottom blade protrudes more in the axial direction than the roughing bottom blade. In this way, a cutting edge replaceable cutting tool characterized by performing front face cutting of a work material .   2. The cutting edge replacement type cutting tool according to claim 1, wherein an inclination angle θ <b> 1 with respect to a radial direction of the rough cutting corner blade is in a range of 10 ° to 30 °.   The cutting edge replacement type cutting tool according to claim 1 or 2, wherein the outer peripheral cutting edge for roughing protrudes in a radial direction from the outer peripheral cutting edge for finishing, and the protruding amount E is 0.5 mm or less. A cutting-edge-replaceable cutting tool.   The cutting insert according to any one of claims 1 to 3, wherein the finishing insert is detachably mounted on the insert mounting seat provided in the tool body. A cutting edge exchangeable cutting tool, characterized in that an adjustment mechanism for adjusting the mounting position of the blade in the axial direction is provided. Cutting edge exchange type with multiple insert mounting seats provided on the outer periphery of the tip end of the tool body that rotates about the axis, with inserts for roughing and finishing inserts attached alternately and circumferentially at equal intervals. In a cutting method in which a cutting material is used to perform front face cutting of a work material, a corner portion where the roughing bottom blade and the roughing outer peripheral blade intersect in the above-described roughing insert is chamfered to form a roughing corner blade. In addition to the above, the corner portion where the finishing bottom blade and the finishing outer peripheral blade that are in the shape of a circular arc convex toward the tip end in the axial direction of the above-mentioned finishing insert are chamfered to provide a finishing corner blade. In the above rough cutting corner blade, the height in the axial direction is h1 (mm), the length in the radial direction is c1 (mm), and the inclination angle with respect to the radial direction is θ1 (°). The radius of curvature of the bottom edge for finishing, which has a convex arc shape toward the tip end in the axial direction, is R (mm), the height in the axial direction of the corner blade for finishing is h2 (mm), and the radius When the length in the direction is c2 (mm), the inclination angle with respect to the radial direction is θ2 (°), and the feed amount per blade of the finishing insert is fz (mm / blade), h1 ≦ 0 .6, h2> h1, 100 ≦ R ≦ 500, θ1 <θ2 and the above c1 and c2 and fz satisfy the condition of (c2−c1)> fz / 2. A cutting method characterized in that the bottom cutting edge of the workpiece is protruded toward the tip end side in the axial direction from the rough cutting bottom edge to perform the front cutting of the work material. 6. The cutting method according to claim 5, wherein the cutting depth in the axial direction by the cutting edge-replaceable cutting tool is set to a height h1 or less in the axial direction of the roughing corner blade in the roughing insert. Cutting method to do.

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