CN219443583U - Milling cutter for pipeline machining - Google Patents

Abstract

The utility model relates to a milling cutter technical field, specifically disclose a milling cutter for pipeline processing, it includes straight shank, interior milling cutter helical blade, outer milling cutter helical blade, interior milling cutter blade, outer milling cutter blade, straight shank tip rigid coupling has the mounting disc, the coaxial rigid coupling of interior milling cutter helical blade tip has the installation pole, the coaxial rigid coupling of outer milling cutter helical blade tip has the connecting rod; the mounting plate is provided with an installing and detaching assembly for realizing detachable connection with the mounting rod; the mounting plate is provided with a connecting component for realizing detachable connection with the connecting rod; the inner milling cutter blade is coaxial and can be detachably arranged at the end part of the spiral edge of the inner milling cutter blade. The utility model provides a have and change interior milling cutter blade alone, or change the installation pole simultaneously with interior milling cutter helical blade and interior milling cutter blade, the pertinence changes and is favorable to saving material, avoids causing extravagant effect.

Description

Milling cutter for pipeline machining

Technical Field

The application relates to the technical field of milling cutters, in particular to a milling cutter for pipeline machining.

Background

The milling cutter is mainly used for milling a workpiece (such as an automobile workpiece, a pipeline or other numerical control parts, and the like), and is provided with one or more cutter tooth-shaped cutting edges, when the milling cutter works, each cutter tooth sequentially and intermittently cuts off the allowance of the workpiece, and the milling cutter can process planes, steps, grooves, forming surfaces, cut off the workpiece, and the like; milling cutters can be divided into: the flat milling cutter is mainly used for milling a face and a groove; the ball knife is used for processing a curved surface; a circular nose knife; a face milling cutter, wherein a machining plane is the main part; the chamfering tool is used for deburring; and other milling tools such as saw blade milling tools, taper milling tools, dovetail milling tools, ball milling tools, thread milling tools, T-shaped milling tools, etc. are used to machine different shapes and materials.

For pipe machining, the milling cutter can be used for machining the inner circumferential wall, such as removing a part of the inner part of the pipe, forming an inclined inner wall so as to provide space for other adapting workpieces (such as refrigeration rings) or form a gradually changing inner diameter at the joint part of the pipe to be matched with the inner diameter of the second pipe; the milling cutter can also be used for machining the peripheral wall of the pipeline, such as cutting threads on the outer wall of the pipeline by using a thread milling cutter.

The chinese patent with publication number CN212976869U proposes an internal milling cutter for processing pipeline, including straight shank, connecting block, chip outlet, internal milling cutter neck and external milling cutter neck, straight shank left end fixed connection connecting block, the chip outlet has been seted up on the connecting block, the internal milling cutter neck of fixed connection on the connecting block left surface, internal milling cutter helical blade of internal milling cutter neck left end fixed connection, internal milling cutter helical blade of internal milling cutter helical blade left end fixed connection, external milling cutter neck of fixed connection on the connecting block left surface, external milling cutter helical blade of external milling cutter neck left end fixed connection, external milling cutter helical blade left end fixed connection can utilize internal milling cutter helical blade and external milling cutter helical blade direct processing production pipeline's inner wall and outer wall, can utilize chip outlet be convenient for discharge the sweeps of output, reduce the resistance that the edge received at the during operation

Aiming at the related technology, the outer milling cutter blade is fixedly connected to the outer milling cutter helical blade, the inner milling cutter blade is fixedly connected to the inner milling cutter helical blade, and the inner milling cutter helical blade and the inner milling cutter neck, the inner milling cutter neck and the connecting block, the outer milling cutter helical blade and the outer milling cutter neck, and the outer milling cutter neck and the connecting block are all fixedly connected; in the case of long-term use of the milling cutter device for milling pipes, in particular the inner milling cutter blades are very prone to wear, if only the inner milling cutter blades wear, but the parts of the entire milling cutter device need to be replaced, material waste is caused, and improvement is needed.

Disclosure of Invention

In order to solve the problem that too many replacement parts cause material waste after milling cutter blades are worn, the application provides a milling cutter for pipeline machining.

The application provides a milling cutter for pipeline processing adopts following technical scheme:

the milling cutter for pipeline processing comprises a straight shank, an inner milling cutter spiral blade, an outer milling cutter spiral blade, an inner milling cutter blade and an outer milling cutter blade, wherein the end part of the straight shank is fixedly connected with a mounting disc, the end part of the inner milling cutter spiral blade is coaxially and fixedly connected with a mounting rod, and the end part of the outer milling cutter spiral blade is coaxially and fixedly connected with a connecting rod;

the mounting plate is provided with an installing and detaching assembly for realizing detachable connection with the mounting rod;

the mounting plate is provided with a connecting component for realizing detachable connection with the connecting rod;

the inner milling cutter blade is coaxial and can be detachably arranged at the end part of the spiral edge of the inner milling cutter blade.

Through adopting above-mentioned technical scheme, install and tear subassembly realization inner milling cutter helical blade and dismantle the setting on the mounting disc, coupling assembling realizes that outer milling cutter helical blade can dismantle the setting on the mounting disc, simultaneously, inner milling cutter blade can dismantle the setting on inner milling cutter helical blade, after long-term use, can change inner milling cutter blade alone according to specific wearing and tearing circumstances, perhaps change simultaneously installation pole together with inner milling cutter helical blade and inner milling cutter blade through install and tear the subassembly, so the pointedly change is favorable to saving material, avoids causing extravagant.

Optionally, the mounting and dismounting assembly comprises a connecting block coaxially fixedly connected to the mounting rod and a stop block fixedly mounted at the end part of the connecting block far away from the mounting rod, wherein the vertical section size of the stop block is larger than that of the connecting block;

the mounting plate is provided with a through hole for the connecting block to pass through, and the end face of the straight shank is provided with a jack which is in plug-in fit with the stop block;

and the straight shank is provided with a limiting component for limiting the stop block to slide out of the straight shank at the jack.

Through adopting above-mentioned technical scheme, when needs installation pole, only need wear out the perforation with the connecting block and insert in the jack, accomplish the installation location of installation pole when the dog slides to the diapire department of jack, the lateral wall of dog offsets with the inner wall of jack to the straight shank is through the socket inner wall to the dog and the accepting of installing the piece atress, and cooperation spacing subassembly makes connecting block and dog can not follow the jack roll-off, can accomplish installation pole and last interior milling cutter helical blade, interior milling cutter blade.

Optionally, the limiting component comprises an insert block slidably arranged in the connecting block and a driving screw rod rotationally connected with the insert block, and the insert block is movably abutted with the stop block;

the straight shank is provided with a drive threaded hole for the drive screw to pass through,

the straight shank is provided with an anti-rotation piece for limiting the rotation of the connecting block.

By adopting the technical scheme, the driving screw is rotated, and the insert block which is rotationally connected with the driving screw is driven to vertically lift under the action of the threaded engagement of the driving screw and the driving threaded hole, so that when the connecting block and the stop block are required to be inserted into the jack, the driving screw is rotated to enable the insert block to move upwards, and interference caused by the insert block when the stop block slides into the jack is prevented; when the stop block slides to be propped against the inner wall of the jack, the driving screw is rotated, so that the driving screw drives the insert block to descend, the insert block descends to be propped against the side wall of the stop block, and the stop block can be limited to move along the axis direction of the straight shank, so that the stop block and the connecting block cannot be separated from the jack.

Optionally, the anti-rotation piece is set to the perpendicular rigid coupling in the anti-rotation strip of connecting block roof, anti-rotation strip length direction is followed the axis direction of straight shank extends, the inserted block is close to the tip of anti-rotation strip seted up with the biting groove of anti-rotation strip interlock adaptation.

Through adopting above-mentioned technical scheme, the inserted block falls to when offing with the dog, the biting groove and the interlock adaptation of preventing changeing the strip of seting up on the inserted block to the inserted block restriction prevents changeing the strip and rotates along straight shank axis direction, and then the corresponding restriction connecting block of inserted block rotates along straight shank axis direction, can not take place relative rotation when making interior milling cutter helical blade, the interior milling cutter blade on the installation pole use, stability is higher.

Optionally, the connecting assembly includes a connecting screw coaxially fixedly connected to the end of the connecting rod and a locking nut in threaded fit with the connecting screw, the mounting plate is provided with a through hole for the connecting screw to pass through, the connecting screw passes through the through hole and is in threaded connection with the locking nut, and the side end surface of the locking nut abuts against the side wall of the mounting plate;

and a limiting piece for limiting the rotation of the connecting screw is arranged on the mounting plate.

By adopting the technical scheme, when the connecting rod is required to be installed, the connecting screw rod only needs to penetrate out of the side wall of the installation plate from the through hole, and the locking nut is screwed to be fixed, so that the side wall of the locking nut is abutted against the side wall of the installation plate, and the fixing of the installation rod can be realized; the limiting piece is arranged to limit the rotation of the screw, so that the service stability of the external milling blade and the external milling cutter helical blade is higher.

Optionally, the limiting piece sets up to support tight bolt, offer on the periphery wall of mounting disc with support tight screw that the through-hole link up, support tight bolt in support tight screw department screw thread wear behind the mounting disc periphery wall its tip with the connecting screw periphery wall offsets.

Through adopting above-mentioned technical scheme, when rotating the tight bolt that supports, support and can remove along the direction that is close to the screw rod under the screw thread meshing effect of tight bolt and tight screw, until the tip that supports tight screw rod offsets with the connecting screw rod peripheral wall, can restrict the rotation of connecting screw rod to it is higher to promote the stability in use of outer milling cutter piece and outer milling cutter helical blade.

Optionally, an external thread cylinder is coaxially and fixedly connected on the internal milling blade, threads are formed on the peripheral wall of the external thread cylinder, and a countersunk hole which is communicated with the inside of the external thread cylinder is formed in the middle of the internal milling blade;

an internal thread mounting hole matched with the external thread cylinder is formed in the end face of the internal milling cutter spiral blade;

the internal milling cutter screw blade is provided with a reinforcing bolt, the bottom wall of the internal thread mounting hole is coaxially provided with a reinforcing threaded hole, and the reinforcing bolt penetrates out of the external thread cylinder and then is in threaded connection with the internal milling cutter screw blade at the reinforcing threaded hole.

Through adopting above-mentioned technical scheme, external screw thread section of thick bamboo screw thread is threaded on the internal milling cutter helical blade through internal thread mounting hole screw thread, accomplishes the preliminary fixed to the internal milling cutter blade, then with the reinforcing bolt screw in the reinforcing screw hole, the reinforcing bolt is further fixed in the internal milling cutter helical blade tip with the internal milling cutter blade for the internal milling cutter blade can not take place to rotate for the internal milling cutter helical blade, thereby promotes the stability that the internal milling cutter blade used.

Optionally, the reinforcement bolt end does not protrude beyond the counterbore.

Through adopting above-mentioned technical scheme, strengthen the bolt tip and hide in the counter bore for it is better to mill bits effect when the interior milling cutter piece uses, can not appear strengthening the phenomenon that the bolt will mill bits hole bottom wall and chisel out the crack, simultaneously, makes the aesthetic property promote when interior milling cutter piece installs.

Optionally, a plurality of chip removal holes for discharging the scraps are formed in the mounting plate, and the inner wall of each chip removal hole is inclined towards the direction close to the straight shank along the thickness of the mounting plate.

Through adopting above-mentioned technical scheme, the chip removal hole sets up a plurality ofly, and the sweeps more are convenient for slide out along the incline direction of chip removal hole under the action of gravity, reduce the sweeps and pile up the inconvenience that causes milling bits frictional force increase etc..

In summary, the present application includes at least one of the following beneficial technical effects:

1. the assembly and disassembly assembly is used for realizing that the inner milling cutter helical blade is detachably arranged on the mounting disc, the connection assembly is used for realizing that the outer milling cutter helical blade is detachably arranged on the mounting disc, meanwhile, the inner milling cutter blade is detachably arranged on the inner milling cutter helical blade, after the inner milling cutter helical blade is used for a long time, the inner milling cutter blade can be independently replaced according to specific abrasion conditions, or the mounting rod, the inner milling cutter helical blade and the inner milling cutter blade colleague are replaced through the assembly and disassembly assembly, so that the targeted replacement is beneficial to saving materials and avoiding waste;

2. the driving screw is rotated, so that the driving screw drives the insert block to descend, the insert block descends to be propped against the side wall of the stop block, and the stop block can be limited to move along the axial direction of the straight shank, so that the stop block and the connecting block cannot be separated from the jack;

3. the biting groove formed in the inserting block is matched with the anti-rotation strip in a biting mode, so that the inserting block is limited to rotate along the axis direction of the straight shank, the connecting block is also limited to rotate along the axis direction of the straight shank, and the inner milling cutter spiral blade and the inner milling cutter blade on the mounting rod cannot rotate relatively when in use, and are higher in stability.

Drawings

Fig. 1 is a schematic overall structure of an embodiment of the present application.

Fig. 2 is a schematic cross-sectional view taken along line A-A in fig. 1.

Fig. 3 is a schematic diagram of an explosive structure in an embodiment of the present application.

Reference numerals: 1. a straight shank; 11. an internal milling cutter helical blade; 111. a mounting rod; 112. an internal thread mounting hole; 113. reinforcing the threaded hole; 12. an external milling cutter helical blade; 121. a connecting rod; 13. a jack; 14. driving the threaded hole; 2. a mounting plate; 21. perforating; 22. a through hole; 23. tightly propping against the screw hole; 24. chip removal holes; 3. an inner milling blade; 31. an external thread cylinder; 32. a countersunk hole; 33. reinforcing bolts; 4. an outer milling blade; 5. an assembling and disassembling component; 51. a connecting block; 511. an anti-rotation bar; 52. a stop block; 6. a limit component; 61. inserting blocks; 611. a biting groove; 62. driving a screw; 7. a connection assembly; 71. a connecting screw; 72. a locking nut; 73. and (5) abutting the bolt.

Detailed Description

The present application is described in further detail below in conjunction with figures 1-3.

The embodiment of the application discloses a milling cutter for pipeline processing.

Referring to fig. 1 and 2, the milling cutter for pipe machining comprises a straight shank 1, an inner milling cutter helical blade 11, an outer milling cutter helical blade 12, an inner milling cutter blade 3 and an outer milling cutter blade 4, wherein the end part of the straight shank 1 is fixedly connected with a mounting disc 2, the end part of the inner milling cutter helical blade 11 is coaxially and fixedly connected with a mounting rod 111, and the end part of the outer milling cutter helical blade 12 is coaxially and fixedly connected with a connecting rod 121; the mounting plate 2 is provided with a plurality of chip discharging holes 24 for discharging the scraps, and the inner walls of the chip discharging holes 24 incline towards the direction approaching the straight shank 1 along the thickness of the mounting plate 2.

When in use, the straight shank 1 is coaxially and fixedly arranged on an output shaft of a machine tool, the output shaft drives an inner milling cutter helical blade 11 and an outer milling cutter helical blade 12 on the output shaft to rotate, and the inner milling cutter helical blade 11 drives the inner milling cutter blade 3 to rotate and the outer milling cutter helical blade 12 drives the outer milling cutter blade 4 to rotate; the inner milling blade 3 mills the hole to the pipeline, the inner milling blade helical blade 11 deburrs and polishes the milled groove, the outer milling blade 4 and the outer milling blade can correspondingly and synchronously polish or mill the hole on the outer wall of the pipeline, and the chips in the pipeline can be discharged from the chip removal hole 24, so that inconvenience caused by accumulation in hole milling operation is reduced.

Referring to fig. 2 and 3, an assembly 5 for detachably connecting with a mounting rod 111 is provided on the mounting plate 2, the assembly 5 comprises a connecting block 51 coaxially fixedly connected to the mounting rod 111, and a stop block 52 fixedly mounted at the end of the connecting block 51 far away from the mounting rod 111, wherein the vertical section size of the stop block 52 is larger than that of the connecting block 51, the vertical section of the stop block 52 is rectangular, and the whole connecting block 51 is cuboid, so that the two have higher torsion resistance and shear resistance.

The mounting plate 2 is correspondingly provided with a through hole 21 for the connecting block 51 to pass through, the end face of the straight shank 1 is provided with a jack 13 which is coaxial with the through hole 21 and is in plug-in fit with the stop block 52, and it is noted that the through hole 21 and the jack 13 are both provided with square holes with shapes matched with the connecting block 51 so as to preliminarily limit the rotation of the connecting block 51.

Referring to fig. 2 and 3, to limit the sliding out of the stopper 52 from the straight shank 1 at the jack 13, the straight shank 1 is provided with a limiting component 6, the limiting component 6 comprises an insert block 61 vertically sliding in the connecting block 51 and a driving screw 62 rotationally connected with the insert block 61, the outer wall of the straight shank 1 is provided with a driving threaded hole 14 for the driving screw 62 to pass through, the driving threaded hole 14 is communicated with the jack 13, so that the driving screw 62 can rotate to drive the insert block 61 to lift, and when the insert block 61 descends to the side wall of the insert block 61 to abut against the stopper 52, the stopper 52 and the connecting block 51 can be limited to slide out from the jack 13.

The two sets of limiting assemblies 6 in the embodiment are arranged, and the two sets of limiting assemblies 6 are respectively arranged on the upper side and the lower side of the vertical direction of the connecting block 51, so that the connecting block 51 can be clamped and fixed while the two inserting blocks 61 are limited, and the coaxiality between the connecting block 51, the mounting rod 111 and the straight shank 1 is ensured.

Further, referring to fig. 3, the straight shank 1 is provided with an anti-rotation member for limiting the rotation of the connection block 51, the anti-rotation member is arranged as an anti-rotation strip 511 vertically fixedly connected to the top wall of the connection block 51, the length direction of the anti-rotation strip 511 extends along the axis direction of the straight shank 1, the end part of the insertion block 61, which is close to the anti-rotation strip 511, is further provided with a biting groove 611 which is matched with the anti-rotation strip 511 in a biting manner, so that two side walls of the biting groove 611 limit the two sides of the anti-rotation strip 511 along the width direction, and the anti-collision strip is difficult to rotate in the insertion hole 13.

Referring to fig. 2 and 3, a connection assembly 7 for detachably connecting with a connection rod 121 is provided on a mounting plate 2, the connection assembly 7 includes a connection screw 71 coaxially fixedly connected to an end of the connection rod 121, a locking nut 72 screwed with the connection screw 71, and a through hole 22 through which the connection screw 71 passes is provided on the mounting plate 2.

It should be noted that, the aperture of the through hole 22 and the aperture of the connecting screw 71 are smaller than the diameter of the connecting rod 121, so that when the connecting screw 71 passes through the through hole 22, the side wall of the connecting rod 121 will be in abutting interference with the side wall of the mounting plate 2 at the position of the through hole 22, but will not pass through the through hole 22 along with the connecting screw 71, so that the connecting rod 121 achieves preliminary positioning of the connecting screw 71, when the connecting screw 71 passes through the through hole 22, the locking nut 72 is screwed to the end part thereof, and the locking nut 72 is screwed until the side end surface of the locking nut abuts against the side wall of the mounting plate 2; at this time, the lock nut and the side end of the connecting rod 121 are abutted against the side wall of the mounting disc 2, so that stable mounting of the connecting rod 121 can be realized.

At this time, to further enhance the installation effect, a restriction member for restricting the rotation of the connection screw 71 is provided on the installation plate 2; in one embodiment, the limiting piece can be set as a bolt, and a plurality of pin holes which are in plug-in fit with the bolt are correspondingly formed in the peripheral wall of the connecting screw 71 to realize rotation prevention; in another embodiment, the restriction member may be provided to abut against the bolt 73, so that the abutment bolt 73 abuts against the outer periphery of the connection bolt to achieve the anti-rotation effect.

The limiting piece in the embodiment is set as a propping bolt 73, wherein a propping screw hole 23 communicated with the through hole 22 is formed on the peripheral wall surface of the mounting plate 2, and the end part of the propping bolt 73 is propped against the peripheral wall of the connecting screw 71 after the thread of the propping bolt 73 penetrates out of the peripheral wall of the mounting plate 2 at the propping screw hole 23; meanwhile, a circle of rubber pads (not shown in the figure) are fixedly connected to the outer peripheral wall of the through hole 22, so that friction force is improved when the connecting bolt is in contact with the mounting plate 2, and the anti-rotation effect is further enhanced.

In addition, referring to fig. 2 and 3, the inner milling blade 3 is coaxially and detachably arranged at the end part of the inner milling blade helical blade 11, an external thread cylinder 31 is coaxially and fixedly connected on the inner milling blade 3, threads are formed on the outer peripheral wall of the external thread cylinder 31, and a countersunk hole 32 which is communicated with the inside of the external thread cylinder 31 is formed in the middle part of the inner milling blade 3; an internal thread mounting hole 112 matched with the external thread cylinder 31 is formed in the end face of the internal milling cutter helical blade 11; therefore, when the inner milling cutter blade 3 is fixed, the inner milling cutter blade 3 can be primarily screwed on the inner milling cutter screw blade 11 only by screwing the external thread cylinder 31 on the inner milling cutter blade into the inner thread mounting hole 112.

Further, the reinforcing bolt 33 is arranged on the spiral blade 11 of the internal milling cutter, and the bottom wall of the internal thread mounting hole 112 is coaxially provided with a reinforcing threaded hole 113; when the inner milling cutter blade 3 is preliminarily screwed on the end face of the inner milling cutter helical blade 11, the small end of the reinforcing bolt 33 sequentially penetrates out of the countersink 32 and the external thread cylinder 31 and reaches the reinforcing threaded hole 113 to be in threaded connection with the inner milling cutter helical blade 11, the reinforcing bolt 33 is screwed, the large end of the reinforcing bolt 33 can be abutted against the bottom wall of the countersink 32, and the inner milling cutter blade 3 can be further limited to rotate relative to the inner milling cutter helical blade 11 under the action of friction force, so that the service stability of the inner milling cutter blade is improved.

It is to be noted that when the reinforcing bolt 33 is fully screwed, the large end portion of the reinforcing bolt 33 does not protrude beyond the counter bore 32 so that the reinforcing bolt 33 does not affect the milling effect of the internal milling cutter.

In other embodiments, the disassembly connection mode of the inner milling cutter blade 3 and the inner milling cutter helical blade 11 can also be realized by a plurality of screws or disassembly bolts; at the same time, the outer milling insert 4 can also be connected coaxially and detachably to the outer milling cutter helical edge 12 in the manner described above.

The implementation principle of the milling cutter for pipeline processing in the embodiment of the application is as follows: after long-term use, if the inner milling cutter blade 3 wears, the outer thread cylinder 31 can be reversely screwed at the inner thread mounting hole 112 by unscrewing the reinforcing bolt 33, so that the inner milling cutter blade 3 is detached from the inner milling cutter helical blade 11.

When the inner milling blade 3 and the inner milling blade helical blade 11 are worn and need to be replaced, only the driving screw 62 is required to be rotated in the direction, so that the insert block 61 slides gradually in the direction far away from the connecting block 51 and is separated from the engagement with the anti-rotation strip 511, the connecting block 51 is immediately drawn out of the insert block 61, convenient disassembly is realized, and material waste is reduced.

The foregoing are all preferred embodiments of the present application, and are not intended to limit the scope of the present application in any way, therefore: all equivalent changes in structure, shape and principle of this application should be covered in the protection scope of this application.

Claims (9)

1. The utility model provides a milling cutter for pipeline processing, includes straight shank (1), interior milling cutter helical blade (11), outer milling cutter helical blade (12), interior milling cutter blade (3), outer milling cutter blade (4), its characterized in that: the end part of the straight shank (1) is fixedly connected with a mounting disc (2), the end part of the inner milling cutter spiral blade (11) is coaxially and fixedly connected with a mounting rod (111), and the end part of the outer milling cutter spiral blade (12) is coaxially and fixedly connected with a connecting rod (121);

the mounting disc (2) is provided with an installing and detaching assembly (5) for realizing detachable connection with the mounting rod (111);

the mounting plate (2) is provided with a connecting component (7) for realizing detachable connection with the connecting rod (121);

the inner milling cutter blade (3) is coaxial and can be detachably arranged at the end part of the inner milling cutter spiral blade (11), and the outer milling cutter blade (4) is coaxial and can be detachably arranged at the end part of the outer milling cutter spiral blade (12).

2. The milling cutter for pipe machining according to claim 1, wherein: the mounting and dismounting assembly (5) comprises a connecting block (51) coaxially fixedly connected to the mounting rod (111) and a stop block (52) fixedly mounted at the end part of the connecting block (51) far away from the mounting rod (111), wherein the vertical section size of the stop block (52) is larger than that of the connecting block (51);

the mounting disc (2) is provided with a through hole (21) for the connecting block (51) to penetrate out, and the end face of the straight shank (1) is provided with a jack (13) which is in plug-in fit with the stop block (52);

the limit component (6) for limiting the stop block (52) to slide out of the straight shank (1) at the jack (13) is arranged on the straight shank (1).

3. The milling cutter for pipe machining according to claim 2, wherein: the limiting assembly (6) comprises an inserting block (61) arranged in the connecting block (51) in a sliding manner and a driving screw (62) rotationally connected with the inserting block (61), and the inserting block (61) is movably abutted with the stop block (52);

a drive threaded hole (14) for the drive screw (62) to penetrate out is formed in the straight shank (1);

the straight shank (1) is provided with an anti-rotation piece for limiting the rotation of the connecting block (51).

4. A milling cutter for pipe machining according to claim 3, wherein: the anti-rotation piece is arranged to be vertically fixedly connected to an anti-rotation strip (511) on the top wall of the connecting block (51), the length direction of the anti-rotation strip (511) extends along the axis direction of the straight shank (1), and a biting groove (611) which is matched with the anti-rotation strip (511) in a biting mode is formed in the end portion, close to the anti-rotation strip (511), of the insertion block (61).

5. The milling cutter for pipe machining according to claim 1, wherein: the connecting assembly (7) comprises a connecting screw rod (71) coaxially fixedly connected to the end part of the connecting rod (121) and a locking nut (72) in threaded fit with the connecting screw rod (71), a through hole (22) for the connecting screw rod (71) to penetrate out is formed in the mounting disc (2), the connecting screw rod (71) penetrates out of the through hole (22) and then is in threaded connection with the locking nut (72), and the side end surface of the locking nut (72) abuts against the side wall of the mounting disc (2);

the mounting plate (2) is provided with a limiting piece for limiting the rotation of the connecting screw (71).

6. The milling cutter for pipe machining according to claim 5, wherein: the limiting piece is arranged to be a tight-propping bolt (73), a tight-propping screw hole (23) communicated with the through hole (22) is formed in the peripheral wall surface of the mounting disc (2), and the end part of the tight-propping bolt (73) penetrates out of the peripheral wall of the mounting disc (2) through threads at the tight-propping screw hole (23) and then is propped against the peripheral wall of the connecting screw rod (71).

7. The milling cutter for pipe machining according to claim 1, wherein: an external thread cylinder (31) is coaxially and fixedly connected to the internal milling blade (3), threads are formed on the peripheral wall of the external thread cylinder (31), and a countersunk hole (32) communicated with the inside of the external thread cylinder (31) is formed in the middle of the internal milling blade (3);

an internal thread mounting hole (112) matched with the external thread cylinder (31) is formed in the end face of the internal milling cutter spiral blade (11);

the internal milling cutter screw blade (11) is provided with a reinforcing bolt (33), the bottom wall of the internal thread mounting hole (112) is coaxially provided with a reinforcing threaded hole (113), and the reinforcing bolt (33) is threaded with the internal milling cutter screw blade (11) at the reinforcing threaded hole (113) after penetrating out from the inside of the external thread cylinder (31).

8. The milling cutter for pipe machining according to claim 7, wherein: the end of the reinforcing bolt (33) does not extend out of the counter bore (32).

9. The milling cutter for pipe machining according to claim 1, wherein: the mounting plate (2) is provided with a plurality of chip removal holes (24) for discharging the scraps, and the inner wall of each chip removal hole (24) is inclined towards the direction close to the straight shank (1) along the thickness of the mounting plate (2).