CN212310573U

CN212310573U - Pipe punching die

Info

Publication number: CN212310573U
Application number: CN202020623305.9U
Authority: CN
Inventors: 王中山; 王小刚; 冯大将; 王锰涛; 王戈炜
Original assignee: Zhangjiagang Solid Aluminum Metal Products Co ltd
Current assignee: Jiangsu Gulu Technology Co.,Ltd.
Priority date: 2020-04-23
Filing date: 2020-04-23
Publication date: 2021-01-08
Anticipated expiration: 2030-04-23

Abstract

The utility model discloses a low-cost high-precision hole-aligning processing punching die for pipes, which comprises an upper die base and a lower die base, wherein two core rod holes are horizontally arranged on the core rod base at a left-right relative interval, a core rod matched with an inner cavity of a pipe to be processed is fixedly arranged in each core rod hole, the front end part of each core rod is suspended forwards and is protruded out of the core rod base in a horizontal state, the front end of each core rod is provided with a core rod punch hole, after the pipe to be processed is sleeved on the core rod and the end part of the pipe is propped against the front side wall of the core rod base, the part of the pipe needing to be punched is just positioned above the core rod punch hole, the bottom of the upper die base is fixedly provided with two punch heads corresponding to the core rod punch holes on the two core rods, when the upper die base is close to the lower die base, each punch head can be close to and inserted into the corresponding punch hole under the, and a punching positioning device for positioning the pipe punching is also arranged below one of the core rods.

Description

Pipe punching die

Technical Field

The utility model relates to a tubular product cut-out press belongs to stamping die technical field.

Background

In the process of precisely machining pipes, the pipes are required to be spaced 180 degrees apart from each other^。The two opposite side walls are punched, at present, when a punching machine is used for punching a pipe, the traditional method is to sleeve the pipe on a core rod matched with the inner cavity of the pipe, a core rod punch hole radially penetrating through the center of the core rod is arranged on the core rod, a punching punch arranged on the punching machine is aligned to the core rod punch hole, and then the punching punch is driven to sequentially penetrate through the upper side wall of the pipe, the core rod punch hole and the lower side wall of the pipe from top to bottom, so that the pipe is processed with a distance of 180 DEG apart^。However, in the process of processing the pipe in this way, on the one hand, the lower side wall portion of the pipe to be punched is easily deformed, and on the other hand, the stroke of the punching punch is long, and when the punching punch reaches the lower side wall of the pipe, the stroke of the punching punch is easily deviated, so that the distance between the lower side wall portion and the lower side wall portion of the pipe is 180 degrees^。The concentricity of the pair of through holes is low, and the processing precision can not meet the design requirement. Therefore, it is necessary to develop a low-cost and high-precision punching die for hole alignment of pipes.

Disclosure of Invention

The utility model aims to provide a: the hole-aligning machining and punching die for the pipes is low in cost and high in precision.

In order to achieve the above object, the utility model provides a following technical scheme: a pipe punching die comprises an upper die holder and a lower die holder, wherein a mandrel holder is fixedly arranged at the rear end of the top of the lower die holder, two mandrel holes are horizontally arranged on the mandrel holder at a left-right opposite interval, a mandrel matched with an inner cavity of a pipe to be processed is fixedly arranged in each mandrel hole, the front end part of each mandrel is suspended forwards and is protruded out of the mandrel holder in a horizontal state, the mandrel on the left side of the mandrel holder is called a first mandrel, the mandrel on the right side of the mandrel holder is called a second mandrel, a mandrel punch hole is arranged at the front end part of each mandrel, when the pipe to be processed is sleeved on the mandrel, and the end part of the pipe is abutted against the front side wall of the mandrel holder, the part of the pipe to be punched is just above the mandrel punch hole, a first punch and a second punch which are respectively corresponding to the mandrel holes on the first mandrel and the second mandrel are fixedly arranged at the bottom of the upper die holder, when the upper die base is close to the lower die base from top to bottom in work, the first punch and the second punch can be driven by the upper die base to be close to each other and respectively inserted into the punch holes of the corresponding core rods, and the lower die base below the second core rods is also provided with a punching positioning device for pipe punching positioning;

the punching positioning device comprises: the lower die holder below the second core rod is provided with a T-shaped guide sliding groove, a T-shaped positioning block capable of sliding back and forth in the guide sliding groove is arranged, the upper end of the T-shaped positioning block upwards extends out of the lower die holder from an opening of the guide sliding groove, the top of the T-shaped positioning block is provided with a positioning convex column located below the second core rod, and the position of the positioning convex column meets the following requirements: when a pipe to be processed is sleeved on the first core rod and a first punch hole is punched on the side wall of the pipe by the first punch, the first punch hole on the pipe is downward sleeved on the positioning convex column, then the pipe is pushed and drives the T-shaped positioning block to move backwards together in the T-shaped guide sliding groove, so that the pipe is sleeved on the second core rod until the end part of the pipe abuts against the front side wall of the core rod seat, and at the moment, the part of the pipe needing to be punched is just above the punch hole of the core rod on the second core rod.

Further, the foregoing pipe punching die, wherein: still be provided with the resetting means who enables T shape locating piece from the back to the front and reply T shape guide chute front end between T shape locating piece and die holder, resetting means includes: the rectangular convex blocks at the left end and the right end of the T-shaped positioning block are respectively provided with a guide hole, two guide rods which are positioned in the T-shaped guide sliding groove and are oppositely arranged at intervals are fixed in the lower die base, each guide rod extends into one corresponding guide hole, each guide rod is sleeved with a spring, when the positioning block receives backward thrust, the positioning block can overcome the elasticity of the spring and slide backwards in the guide sliding groove in the front direction, and when the external thrust disappears, the positioning block can move forwards under the action of the spring until the front end of the guide sliding groove is reset.

Further, the foregoing pipe punching die, wherein: the top of T shape locating piece is provided with and runs through the recess at locating piece top around and with tubular product lateral wall phase-match, and the location projection is located the central line of recess for after having been punched out a first on the lateral wall of tubular product, when overlapping this first punching a hole on the tubular product downwards on the location projection, the recess surface on the locating piece can be laminated with the corresponding lateral wall of this recess on the tubular product.

Further, the foregoing pipe punching die, wherein: a cushion block is fixedly arranged on the lower die holder below the front end part of the first core rod, and a groove which is matched with the outer side wall of the pipe and penetrates through the top of the cushion block from front to back is arranged at the top of the cushion block，When the pipe to be processed is sleeved on the first core rod, the outer side wall of the pipe corresponding to the groove can be attached to the surface of the groove on the cushion block.

Further, the foregoing pipe punching die wherein: still be provided with the positioner in plug drift hole on core rod seat and the plug, the positioner in plug drift hole includes: two positioning convex blocks are fixedly arranged on the left side and the right side of the front side wall of the mandrel seat at opposite intervals, a positioning groove is arranged on the upper side wall of each mandrel, each positioning convex block and one positioning groove are arranged in a vertical corresponding mode, a mandrel pin hole radially penetrating through the center of the mandrel is arranged at the rear end part of each mandrel, two mandrel seat pin holes respectively corresponding to the mandrel pin holes one by one are vertically arranged on the mandrel seat, each mandrel seat pin hole is communicated with one mandrel hole, the rear end of the mandrel is inserted into the corresponding mandrel hole from front to back during installation, until the positioning lug on the core rod is vertically opposite to the corresponding positioning groove, the pin hole of the core rod is just aligned with the pin hole of the core rod seat, and then, inserting the fixing pin into the pin hole of the mandrel holder from top to bottom and into the pin hole of the mandrel until the mandrel is fixed on the mandrel holder, wherein the punch hole of the mandrel is just positioned at a position which can be matched with the corresponding punch to work.

Further, the foregoing pipe punching die, wherein: the bottom of the upper die base is fixedly provided with at least one guide pillar, the mandrel base is provided with guide pillar through holes which are in one-to-one correspondence with the guide pillars and penetrate through the mandrel base from top to bottom, each guide pillar through hole extends downwards into the lower die base, and when the upper die base is close to the lower die base from top to bottom, each guide pillar can be close to and inserted into one corresponding guide pillar through hole under the driving of the upper die base.

Further, the foregoing pipe punching die, wherein: the lower die holder comprises: the lower die base plate and the lower backing plate are located above the lower die base plate, the lower backing plate is detachably and fixedly connected with the lower die base plate, the mandrel seat is fixed at the rear end of the top of the lower backing plate, the T-shaped guide sliding groove is located in the lower backing plate below the second mandrel, and the T-shaped guide sliding groove penetrates through the lower backing plate from top to bottom, so that the upper side wall of the lower die base plate located below the T-shaped guide sliding groove forms the bottom wall of the T-shaped guide sliding groove, when the T-shaped positioning block is placed in the T-shaped guide sliding groove, the bottom wall of the T-shaped positioning block can be attached to the upper surface of the lower die base plate corresponding to the T-shaped guide sliding groove, and the.

The utility model has the advantages that: the punching die for the pipe is simple in structure and low in manufacturing cost, the stroke of the punch is short when the pipe is processed by the punching die for the pipe, stroke deviation cannot occur, the lower side wall of the pipe is not prone to deformation in the punching process, and the distance between the side wall of the pipe and the side wall of the pipe is 180 DEG^。The hole aligning precision is higher; secondly, the grooves formed in the cushion block and the grooves formed in the T-shaped positioning blocks enable part of pressure to be borne by the cushion block and the positioning blocks during punching, and the core rod is not prone to fracture; and thirdly, the labor intensity of workers is reduced by using the reset device.

Drawings

Fig. 1 is a schematic structural view of a pipe punching die according to the present invention;

FIG. 2 is a schematic top view of the lower plate, punch locating device and spacer;

FIG. 3 is a schematic front view of a T-shaped positioning block;

FIG. 4 is a schematic top view of a second mandrel;

fig. 5 is a schematic top view of the mandrel holder.

Detailed Description

The technical solution of the present invention will be further explained with reference to the accompanying drawings and preferred embodiments.

As shown in fig. 1, 4 and 5, a pipe punching die includes: the pipe punching machine comprises an upper die holder 4 and a lower die holder 1, wherein a mandrel holder 2 is fixedly arranged at the rear end of the top of the lower die holder 1, two mandrel holes 26 are horizontally arranged on the mandrel holder 2 at a left-right opposite interval, a mandrel matched with the inner cavity of a pipe 10 to be machined is fixedly arranged in each mandrel hole 26, the front end part of each mandrel is suspended forwards and protrudes out of the mandrel holder 2 in a horizontal state, the mandrel positioned on the left side of the mandrel holder 2 is called a first mandrel 21, the mandrel positioned on the right side of the mandrel holder 2 is called a second mandrel 22, a mandrel punching hole 23 is arranged at the front end part of each mandrel, when the pipe 10 to be machined is sleeved on a certain mandrel, the end part of the pipe 10 to be punched abuts against the front side wall of the mandrel holder 2, the part of the pipe 10 to be punched is just above the mandrel punching hole 23, and the first mandrel 21 is fixedly arranged at the bottom of the upper die holder 4, The first punch 31 and the second punch 32 respectively correspond to the punch holes 23 of the second core rod 22, when the upper die holder 4 is close to the lower die holder 1 in operation, the first punch 31 and the second punch 32 can be close to and respectively inserted into one corresponding punch hole 23 of the core rod under the driving of the upper die holder 4, and the lower die holder 1 below the second core rod 22 is further provided with a punching positioning device for punching and positioning the tube 10.

In this embodiment, the mandrel holder 2 and the mandrel are further provided with a positioning device for the mandrel punch hole 23, and the positioning device for the mandrel punch hole 23 includes: two positioning lugs 25 are fixedly arranged on the front side wall of the mandrel holder 2 at a left-right opposite interval, a positioning groove 27 is arranged on the upper side wall of each mandrel, each positioning lug 25 and one positioning groove 27 are arranged up and down correspondingly, a mandrel pin hole 28 radially penetrating through the center of the mandrel is arranged at the rear end part of each mandrel, two mandrel holder pin holes 24 respectively corresponding to the mandrel pin holes 28 one by one are vertically arranged on the mandrel holder 2, each mandrel holder pin hole 24 is communicated with one mandrel hole 26, the rear end of the mandrel is inserted into the corresponding mandrel hole 26 from front to back during installation until the positioning lug 25 on the mandrel is opposite to the corresponding positioning groove 27 up and down, at the moment, the mandrel pin hole 28 is just aligned with the mandrel holder pin hole 24, then a fixing pin is inserted into the mandrel pin hole 24 from top to bottom and is inserted into the mandrel pin hole 28 until the mandrel is fixed on the mandrel holder 2, the core rod punch hole 23 is now in a position to work with the corresponding punch.

As shown in fig. 2 and 3, the punching positioning device includes: a T-shaped guide chute 8 positioned below the second core rod 22 and a T-shaped positioning block 6 capable of sliding back and forth in the T-shaped guide chute 8 are arranged on the lower die holder 1, the upper end of the T-shaped positioning block 6 extends out of the lower die holder 1 from the opening of the guide chute 8, a positioning convex column 61 positioned below the second core rod 22 is arranged at the top of the T-shaped positioning block 6, and the position of the positioning convex column 61 meets the following requirements: when a pipe 10 to be processed is sleeved on the first core rod 21 and a first punch 31 is used for punching a first punched hole on the side wall of the pipe 10, the first punched hole on the pipe 10 is downward and sleeved on the positioning convex column 61, then the pipe 10 is pushed and drives the positioning block 6 to slide backwards in the T-shaped guide sliding chute 8, so that the pipe 10 is sleeved on the second core rod 22 until the end part of the pipe 10 abuts against the front side wall of the core rod seat 2, and at the moment, the part of the pipe 10 needing to be punched is just above the core rod punch hole 23 on the second core rod 22.

In this embodiment, a reset device capable of returning the T-shaped positioning block 6 to the front end of the T-shaped guide chute 8 from back to front is further disposed between the T-shaped positioning block 6 and the lower die holder 1, and the reset device includes: the rectangular convex blocks 64 at the left end and the right end of the positioning block 6 are respectively provided with a guide hole 63, two guide rods 9 which are arranged in the T-shaped guide sliding groove 8 at the left end and the right end at opposite intervals, the rear end of each guide rod 9 is in threaded connection with the lower die holder 1 and is fixed in the lower die holder 1, the front end of each guide rod 9 extends into one corresponding guide hole 63, each guide rod 9 is sleeved with a spring 91, when the positioning block 6 is pushed backwards, the positioning block 6 can overcome the elasticity of the spring 91 and slide backwards in the guide sliding groove 8 from the front end, and when the external pushing force disappears, under the action of the spring 91, the positioning block 6 can slide forwards until the front end of the guide sliding groove 8 is.

In this embodiment, the top of T shape locating piece 6 is provided with and runs through the recess 62 at locating piece top around and with tubular product 10 lateral wall phase-match,

location projection

61 and 6 threaded connection of locating piece, the top of location projection 61 stretches out recess 62 surface and is located the central line of recess 62, in actual use, need not change whole T shape locating piece 6, can satisfy the location demand of the first punching a hole of equidimension not on tubular product 10 through changing different location projections 61, the effect that sets up and tubular product 10 lateral wall assorted recess 62 on T shape locating piece 6 is: after a first punched hole is punched in the upper side wall of the tube 10, the tube 10 is turned over by 180 degrees^。The lower side wall of the second core rod 22 is made to be upward, the first punched hole is made to be downward, and then when the first punched hole is sleeved on the positioning convex column 61 of the T-shaped positioning block 6, the outer side wall of the pipe 10 corresponding to the groove 62 is attached to the surface of the groove 62 of the positioning block 6, so when the second punch 32 penetrates through the lower side wall of the pipe 10 placed in the groove 62 of the positioning block 6 from top to bottom, as part of impact pressure is borne by the positioning block 6, the impact pressure borne by the second core rod 22 is relatively small, and the second core rod 22 is not easy to break.

In this embodiment, a cushion block 5 is fixedly arranged on the lower die holder 1 below the first mandrel 21, a groove which is matched with the outer side wall of the pipe 10 and penetrates through the top of the cushion block 5 from front to back is arranged at the top of the cushion block 5, after the pipe 10 to be processed is sleeved on the first mandrel 21, the outer side wall of the pipe 10 corresponding to the groove at the top of the cushion block 5 can be attached to the surface of the groove on the cushion block 5, and the effect of the groove arranged on the cushion block 5 is the same as the effect of the groove 62 arranged on the T-shaped positioning block 6.

In this embodiment, at least one guide pillar 7 is fixedly disposed at the bottom of the upper die base 4, a guide pillar through hole 71 which is respectively corresponding to the guide pillars 7 and penetrates through the mandrel base 2 from top to bottom is disposed on the mandrel base 2, each guide pillar through hole 71 extends downward into the lower die base 1, when the upper die base 4 is close to the lower die base 1 from top to bottom, each guide pillar 7 is close to and inserted into one corresponding guide pillar through hole 71 under the driving of the upper die base 4, and then the upper die base 4 drives the guide pillar 7 to move up and down in the guide pillar through hole 71, so that each punch can just extend into and leave one corresponding mandrel punch hole 23.

In this embodiment, in order to facilitate assembling the T-shaped positioning block 6 when manufacturing the tube punching die, the lower die holder 1 includes: the lower die base plate 11 and the lower backing plate 12 are located above the lower die base plate 11, the lower backing plate 12 and the lower die base plate 11 are detachably and fixedly connected, the mandrel base 2 is fixed at the rear end of the top of the lower backing plate 12, the T-shaped guide chute 8 is located in the lower backing plate 12 below the second mandrel 22, and the T-shaped guide chute 8 penetrates through the lower backing plate 12 up and down, so that the upper side wall of the lower die base plate 11 located below the T-shaped guide chute 8 forms the bottom wall of the T-shaped guide chute 8, when the T-shaped positioning block 6 is placed in the T-shaped guide chute 8, the bottom wall of the T-shaped positioning block 6 can be attached to the upper surface of the lower die base plate 11 corresponding to the T-shaped guide chute 8, and the upper end of the T-shaped positioning block 6 extends out.

The use method of the pipe punching die with the structure comprises the following steps: fixing an upper die holder 4 on a sliding block of a punching machine, fixing a lower die holder 1 on a workbench of the punching machine, then sleeving a pipe 10 to be processed on a first core rod 21, enabling the end part of the pipe 10 to abut against the front side wall of a core rod seat 2, opening the punching machine to drive the upper die holder 4 to approach the lower die holder 1, enabling a guide pillar 71 to extend into a guide pillar through hole 71 and move downwards in the guide pillar through hole 71 under the driving of the upper die holder 4 until a first punch 31 penetrates through the upper side wall of the pipe 10 from top to bottom and extends into a core rod punch hole 23 of the first core rod 21 under the driving of the upper die holder 4, so as to punch a first punched hole on the upper side wall of the pipe 10, and then controlling the punching machine to enable the upper die holder 4 to be far away from the lower die holder 1 and take the pipe 10 out of; then the tube 10 is turned over by 180 degrees^。The lower side wall of the tube 10 is made to be upward, the first punched hole is made to be downward, then the first punched hole is sleeved on the positioning convex column 61 of the T-shaped positioning block 6, backward thrust is exerted on the tube 10, the tube 10 drives the positioning block 6 to overcome the elasticity of the spring 91 to slide on the T-shaped guide sliding groove 8 from front to back, the tube 10 is sleeved on the second core rod 22 until the end part of the tube 10 abuts against the second core rod 22After the front side wall of the mandrel seat 2 is arranged, the punching machine is started to drive the upper die seat 4 to approach the lower die seat 1, the second punch 32 penetrates through the lower side wall of the tube 10 from top to bottom under the drive of the upper die seat 4 and extends into the mandrel punch hole 23 of the second mandrel 22, and therefore a distance of 180 degrees is punched on the lower side wall of the tube 10 from the first punch hole^。After the punching is completed, the backward thrust on the tube 10 is removed, the elastic force of the spring 91 enables the positioning block 6 to automatically slide in the guide chute 8 from back to front, so that the positioning block 6 is reset to the front end of the guide chute 8, the tube 10 is also separated from the second core rod, and finally the tube 10 is taken out from the positioning convex column 61, namely the tube 10 is taken out from the side wall of the tube 10 at a distance of 180 degrees^。The pair of holes is processed.

The pipe punching die with the structure has the following advantages: the punching die for the pipe is simple in structure and low in manufacturing cost, the stroke of the punch is short when the pipe is processed by the punching die for the pipe, stroke deviation cannot occur, the lower side wall of the pipe is not prone to deformation in the punching process, and the distance between the side wall of the pipe and the side wall of the pipe is 180 DEG^。The hole aligning precision is higher; secondly, the grooves arranged on the cushion block 5 and the grooves 62 arranged on the T-shaped positioning blocks 6 enable part of pressure to be born by the cushion block 5 and the positioning blocks 6 during punching, and the core rod is not easy to break; and thirdly, the labor intensity of workers is reduced by using the reset device.

Claims

1. A pipe punching die comprises an upper die holder and a lower die holder, and is characterized in that a mandrel holder is fixedly arranged at the rear end of the top of the lower die holder, two mandrel holes are horizontally arranged on the mandrel holder at a left-right opposite interval, a mandrel matched with an inner cavity of a pipe to be machined is fixedly arranged in each mandrel hole, the front end part of each mandrel is horizontally hung forwards and is protruded out of the mandrel holder, the mandrel positioned on the left side of the mandrel holder is called a first mandrel, the mandrel positioned on the right side of the mandrel holder is called a second mandrel, a mandrel punching hole is arranged at the front end part of each mandrel, when the pipe to be machined is sleeved on a certain mandrel, the end part of the pipe abuts against the front side wall of the mandrel holder, the part of the pipe to be punched is just above the mandrel punching hole, and the first mandrel is fixedly arranged at the bottom of the upper die holder, The first punch and the second punch can be driven by the upper die holder to be close to and respectively inserted into the corresponding punch holes of the core rods, and the lower die holder below the second core rod is also provided with a punching positioning device for pipe punching positioning;

2. The tube punching die of claim 1, wherein: still be provided with the resetting means who enables T shape locating piece from the back to the front and reply T shape guide chute front end between T shape locating piece and die holder, resetting means includes: the rectangular convex blocks at the left end and the right end of the T-shaped positioning block are respectively provided with a guide hole, two guide rods which are positioned in the T-shaped guide sliding groove and are oppositely arranged at intervals are fixed in the lower die base, each guide rod extends into one corresponding guide hole, each guide rod is sleeved with a spring, when the positioning block receives backward thrust, the positioning block can overcome the elasticity of the spring and slide backwards in the guide sliding groove in the front direction, and when the external thrust disappears, the positioning block can move forwards under the action of the spring until the front end of the guide sliding groove is reset.

3. The tube punching die of claim 2, wherein: the top of T shape locating piece is provided with and runs through the recess at locating piece top around and with tubular product lateral wall phase-match, and the location projection is located the central line of recess for after having been punched out a first on the lateral wall of tubular product, when overlapping this first punching a hole on the tubular product downwards on the location projection, the recess surface on the locating piece can be laminated with the corresponding lateral wall of this recess on the tubular product.

4. A tube punching die according to claim 3, wherein: a cushion block is fixedly arranged on the lower die holder below the front end part of the first core rod, and a groove which is matched with the outer side wall of the pipe and penetrates through the top of the cushion block from front to back is arranged at the top of the cushion block，When the pipe to be processed is sleeved on the first core rod, the outer side wall of the pipe corresponding to the groove can be attached to the surface of the groove on the cushion block.

5. A tube punching die according to claim 1 or 2 or 3 or 4, characterized in that: still be provided with the positioner in plug drift hole on core rod seat and the plug, the positioner in plug drift hole includes: two positioning convex blocks are fixedly arranged on the left side and the right side of the front side wall of the mandrel seat at opposite intervals, a positioning groove is arranged on the upper side wall of each mandrel, each positioning convex block and one positioning groove are arranged in a vertical corresponding mode, a mandrel pin hole radially penetrating through the center of the mandrel is arranged at the rear end part of each mandrel, two mandrel seat pin holes respectively corresponding to the mandrel pin holes one by one are vertically arranged on the mandrel seat, each mandrel seat pin hole is communicated with one mandrel hole, the rear end of the mandrel is inserted into the corresponding mandrel hole from front to back during installation, until the positioning lug on the core rod is vertically opposite to the corresponding positioning groove, the pin hole of the core rod is just aligned with the pin hole of the core rod seat, and then, inserting the fixing pin into the pin hole of the mandrel holder from top to bottom and into the pin hole of the mandrel until the mandrel is fixed on the mandrel holder, wherein the punch hole of the mandrel is just positioned at a position which can be matched with the corresponding punch to work.

6. The tube punching die of claim 5, wherein: the bottom of the upper die base is fixedly provided with at least one guide pillar, the mandrel base is provided with guide pillar through holes which are in one-to-one correspondence with the guide pillars and penetrate through the mandrel base from top to bottom, each guide pillar through hole extends downwards into the lower die base, and when the upper die base is close to the lower die base from top to bottom, each guide pillar can be close to and extend into one corresponding guide pillar through hole under the driving of the upper die base.

7. The tube punching die of claim 5, wherein: the lower die holder comprises: the lower die base plate and the lower backing plate are located above the lower die base plate, the lower backing plate is detachably and fixedly connected with the lower die base plate, the mandrel seat is fixed at the rear end of the top of the lower backing plate, the T-shaped guide sliding groove is located in the lower backing plate below the second mandrel, and the T-shaped guide sliding groove penetrates through the lower backing plate from top to bottom, so that the upper side wall of the lower die base plate located below the T-shaped guide sliding groove forms the bottom wall of the T-shaped guide sliding groove, when the T-shaped positioning block is placed in the T-shaped guide sliding groove, the bottom wall of the T-shaped positioning block can be attached to the upper surface of the lower die base plate corresponding to the T-shaped guide sliding groove, and the.