CN114515793A

CN114515793A - Pipe expander

Info

Publication number: CN114515793A
Application number: CN202210081665.4A
Authority: CN
Inventors: 刘雄; 严伟杰; 饶纪平; 区章权
Original assignee: Foshan Huize Heat Exchanger Equipment Co ltd
Current assignee: Foshan Huize Heat Exchanger Equipment Co ltd
Priority date: 2022-01-24
Filing date: 2022-01-24
Publication date: 2022-05-20
Anticipated expiration: 2042-01-24
Also published as: CN114515793B

Abstract

The application relates to the technical field of pipe processing equipment, in particular to a pipe expander, which comprises a machine base, wherein the machine base comprises a power base, an expanding base and a limiting base, a guide strip is installed on the power base, a positioning transmission assembly used for driving the guide strip to move upwards in the vertical direction is arranged at the top of the power base, a fin heat exchanger is connected to the middle of the limiting base in a sliding manner and comprises an installation frame and a fin pipe group, the fin pipe group is arranged in the middle of the installation frame and is just opposite to the arrangement between the guide strip and the installation frame, a transmission rod is arranged in the middle of the expanding base, a driving piece used for driving the expanding base to move upwards in the vertical direction is arranged on the transmission rod, an expanding rod group is fixed on the expanding base, and the expanding rod group and the fin pipe group are just opposite to the arrangement, in order to improve the quality of finned tube expansion joint, the application provides a tube expander, appears the skew phenomenon when can reducing the expander roll expansion.

Description

Pipe expander

Technical Field

The application relates to the technical field of pipe machining equipment, in particular to a pipe expander.

Background

The finned heat exchanger is a heat exchange element for improving heat exchange efficiency, a common finned heat exchange tube comprises an installation frame and a finned tube group, the finned tube group is arranged in the installation frame, the finned tube group is arranged to increase the outer surface area of the heat exchange tube so as to achieve the purpose of improving the heat exchange efficiency, the end diameter of the finned tube can be enlarged by using a tube expander generally in the machining process of the finned tube, and the tube expander can also perform end expansion and end flanging on the finned tube according to different purposes.

In the prior art, an operator needs to clamp the finned tube at one end of the rack, then an expansion tube driving assembly is arranged at one end, far away from the finned tube, of the rack, the expansion tube driving assembly serves as a power source to drive an expansion rod to approach the finned tube, and the expansion rod is expanded and connected with the end portion of the finned tube after being stressed, so that expansion of the finned tube is completed.

However, in general, the quality of the finned tube expansion joint is directly influenced by the geometric shape of the end part of the expansion rod and the movement stroke of the expansion rod, and the expansion rod is long, so that the expansion rod is easy to shift during tube expansion, and the quality of the finned tube expansion joint is low.

Disclosure of Invention

In order to improve the quality of finned tube expansion joint, the application provides a tube expander, appears the skew phenomenon when can reducing the expander roll expansion.

The application provides a pipe expander adopts following technical scheme:

the utility model provides a tube expander, includes the frame, the frame includes power seat, flaring seat and spacing seat, install the gib block on the power seat, the top of power seat is provided with and is used for the drive the location transmission subassembly of vertical direction upward movement is done to the gib block, spacing seat middle part sliding connection has finned heat exchanger, finned heat exchanger is including installing frame and finned tube group, finned tube group sets up the middle part of installing frame, the gib block with just to laying between the installing frame, the middle part of flaring seat is provided with the transfer line, be provided with on the transfer line and be used for the drive flaring seat is the driving piece of vertical direction upward movement, be fixed with the expansion link group on the flaring seat, the expansion link group with just to laying between the fin.

By adopting the technical scheme, because the guide strips and the mounting frame are arranged oppositely, under the action of the positioning transmission assembly, can drive the guide bar to do vertical and downward movement, so that the guide bar is easily pressed on the mounting frame, further can compress the fin heat exchanger, can achieve the effect of reducing the offset phenomenon when the expansion rod expands the tube, in addition, under the action of the driving piece, the transmission rod can rotate to enable the flaring seat to move in the vertical direction, meanwhile, the expansion rod group also moves vertically and downwards, so that expansion rod and pipe expansion can be completed, the convenience of expansion rod and pipe expansion is improved, and moreover, the quality of the finned tube expansion joint is favorably ensured, and after the expansion rod expands the tube, the positioning transmission assembly drives the guide strip to vertically upwards, so that the guide strip can be conveniently separated from the finned heat exchanger, and the separation efficiency between the finned heat exchanger and the limiting seat is improved.

Preferably, the expansion rod group includes a plurality of expansion rods, the expansion rod includes: a connecting rod mounted on the flaring seat; the flanging lug is fixed at one end of the connecting rod, which is close to the limiting seat; the flaring block is fixed on the connecting rod and close to the top surface of the flanging convex block; and the stop block is arranged on the connecting rod and close to the top surface of the flaring block, wherein the diameter of the stop block is larger than that of the flaring block.

Through adopting above-mentioned technical scheme, at the in-process of expander roll of pole, the turn-ups lug supports mutually with the finned tube earlier and presses, the turn-ups lug carries out the turn-ups to the finned tube, can provide the effect of direction for the tip expander in later stage to a certain extent, under the effect of pressure, the expander roll continues down the motion, make the flaring piece peg graft at the middle part of finned tube completely, the diapire of stop piece and the roof looks butt of finned tube, and then accomplish the expander roll of pole, the setting of stop piece can be spacing to the motion stroke of expander roll, the quality that the finned tube expands the joint has been improved to a certain extent.

Preferably, an arc-shaped connection part is arranged between the flanging convex block and the flaring block, and the arc-shaped connection part is in smooth transition with the flanging convex block and the flaring block respectively.

By adopting the technical scheme, the arc-shaped joint part is smoothly transited with the flanging convex block and the flaring block respectively, so that burrs on the transition section are reduced to scratch the finned tube, and the quality of the finned tube expansion joint is ensured.

Preferably, the positioning transmission assembly comprises: the locking column is fixed on the top surface of the power seat; the transmission shaft is rotatably connected to the middle part of the locking column; the transmission gear is arranged at one end of the transmission shaft; the locking device comprises a rack arranged on one side, close to the transmission gear, of the guide strip and a first driving motor arranged on the side wall of the locking column, wherein the output end of the first driving motor is assembled with the transmission shaft, and the transmission gear is meshed with the rack.

Through adopting above-mentioned technical scheme, under a driving motor's effect, the transmission shaft can rotate, and simultaneously, drive gear also can rotate to, driving rack rolls on the rack, and driving rack drives the guide strip and carries out the ascending motion of vertical side, promptly, can easily drive the guide strip and support to press on fin heat exchanger, or easily to guide strip, fin heat exchanger phase separation, has improved the motion convenience and the efficiency of guide strip.

Preferably, a hollow groove is formed in the middle of the guide strip in a penetrating mode.

Through adopting above-mentioned technical scheme, through having seted up the cavity recess in the middle part of gib block, can alleviate the whole weight of gib block, and then can easily drive the gib block, and then can reduce first driving motor's power, saved manufacturing cost.

Preferably, an upper die base is installed at the top of the power base, a guide column is arranged between the upper die base and the power base, a lower die base is arranged at the bottom of the limiting base, an installation column is arranged on the top surface of the lower die base, and the part, penetrating out of the power base, of the guide column is connected with the installation column in a sliding mode.

By adopting the technical scheme, the guide column is connected with the mounting column in a sliding manner, so that the relative motion among the upper die base, the power base and the lower die base can be kept on the same straight line, the offset phenomenon during expansion of the expansion rod is reduced, and the quality of the expansion joint of the finned tube is ensured.

Preferably, the top wall of the upper die base is provided with a second driving motor, the output end of the second driving motor is assembled with the transmission rod, one end of the transmission rod is in threaded connection with the flaring seat, and the other end of the transmission rod is in rotary connection with the upper die base.

Through adopting above-mentioned technical scheme, under second driving motor's effect, the transfer line can rotate, and then the ascending motion of vertical side is done to the drive flaring seat, has improved the motion convenience of flaring seat.

Preferably, a fixed seat is installed on the top surface of the lower die holder, the limiting seat is arranged on one side, close to the lower die holder, of the fixed seat, sliding grooves are formed in two opposite side walls of the fixed seat respectively, a connecting sliding block is installed on the side wall of the installing frame, and the connecting sliding block is in sliding connection with the sliding grooves in a matched mode.

Through adopting above-mentioned technical scheme, through carrying out sliding connection to link block and spout, can accomplish being connected between finned heat exchanger and the fixing base, improved finned heat exchanger's installation stability, convenience.

Preferably, a slot is formed in the middle of the limiting seat, the fin heat exchanger is connected with the slot in a sliding mode, a damping layer is arranged on the inner bottom wall of the limiting seat, and the bottom wall of the fin tube group is abutted to the damping layer.

Through adopting above-mentioned technical scheme, setting up of buffer layer makes and is formed with the shock attenuation chamber between buffer layer and the spacing seat, and noise pollution when being favorable to reducing the expander roll, simultaneously, be favorable to reducing the finned tube and directly take place the striking phenomenon with the diapire in the spacing seat, has guaranteed the quality that the finned tube expands and connects.

Preferably, the position of the input end of the limiting seat is provided with a wear-resistant gasket.

Through adopting above-mentioned technical scheme, wear-resisting packing ring has good wearability and impact resistance, is provided with wear-resisting packing ring through the position department at spacing seat input, can reduce the friction between finned tube and the spacing seat, has improved the quality that the finned tube expands to connect to a certain extent.

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

1. the guide strips and the mounting frame are arranged in a right-to-right mode, the guide strips can be driven to move vertically and downwards under the action of the positioning transmission assembly, the guide strips are made to be easily abutted against the mounting frame, and then the fin heat exchanger can be compressed, the effect of reducing the offset phenomenon during expansion of the expansion rods can be achieved, in addition, under the action of the driving piece, the transmission rod can rotate, the flaring seat is made to move vertically, meanwhile, the expansion rod group also moves vertically and downwards, expansion rod expansion can be completed, convenience of expansion rod expansion is improved, the quality of expansion finned tube joints can be guaranteed, after the expansion rod expansion is completed, the positioning transmission assembly drives the guide strips to move vertically and upwards, the guide strips can be conveniently separated from the fin heat exchanger, and separation efficiency between the fin heat exchanger and the limiting seat is improved;

2. at the in-process of expander roll, the turn-ups lug supports mutually with the finned tube earlier and presses, the turn-ups lug carries out the turn-ups to the finned tube, can provide the effect of direction for the tip expander in later stage to a certain extent, under the effect of pressure, the expander roll continues down motion, make the flaring piece peg graft completely at the middle part of finned tube, the diapire of stopping the piece and the roof looks butt of finned tube, and then accomplish the expander roll, the setting of stopping the piece can carry on spacingly to the motion stroke of expander roll, the quality that the finned tube expanded joint has been improved to a certain extent.

Drawings

Fig. 1 is a schematic view of the state of the pipe expander in example 1 in the expansion.

Fig. 2 is a schematic view of the pipe expander of example 1 after expansion.

Fig. 3 is a schematic view of the combination of the expansion rod and the fin heat exchanger in the embodiment 1.

Fig. 4 is a full sectional view of fig. 1.

Fig. 5 is a schematic view of the combination of the expansion rod and the fin heat exchanger in the embodiment 2.

Description of reference numerals: 1. a machine base; 11. an upper die holder; 12. a guide post; 13. a power base; 14. a flaring seat; 15. a limiting seat; 16. mounting a column; 17. a lower die holder; 21. a guide strip; 211. a rack; 212. a hollow groove; 22. a locking post; 221. a transmission gear; 222. a first drive motor; 23. a limiting strip; 231. a matching block; 24. a mating post; 241. a guide groove; 25. a fixing frame; 31. a second drive motor; 32. a transmission rod; 4. expanding rods; 41. a connecting rod; 42. a flanging bump; 43. a flaring block; 44. an arc-shaped joining part; 45. a stop block; 51. fixing the rod; 52. a flanging module; 61. a fixed seat; 611. a chute; 62. connecting the sliding block; 63. inserting the slot; 64. a shock-absorbing layer; 65. a wear-resistant washer; 7. a finned heat exchanger.

Detailed Description

In order to make the purpose, technical solution and advantages of the present application more clear, the present application is further described in detail below with reference to fig. 1 to 5 and the embodiments.

The embodiment of the application discloses a pipe expander.

Example 1:

referring to fig. 1 and 2, the tube expander comprises a machine base 1, wherein the machine base 1 comprises an upper die base 11 and a power base 13, specifically, the upper die base 11 and the power base 13 are arranged in a stacked manner from top to bottom, the upper die base 11 and the power base 13 are both rectangular bases, guide columns 12 are fixed between the upper die base 11 and the power base 13, the number of the guide columns 12 is four, the four guide columns 12 are respectively arranged at the positions of four corners of the upper die base 11, and one ends, far away from the upper die base 11, of the guide columns 12 extend out of the power base 13.

Correspondingly, the lower die base 17 is arranged at the bottom of the power base 13, in the embodiment of the present application, the mounting columns 16 are fixed on the top surface of the lower die base 17, the mounting columns 16 are hollow circular columns, four mounting columns 16 are also provided, the mounting columns 16 and the guide columns 12 are arranged in a right-to-right manner, the guide columns 12 are inserted into the mounting columns 16, and the guide columns 12 and the mounting columns 16 are connected in a sliding manner, which is beneficial to ensuring that the relative motion among the upper die base 11, the power base 13 and the lower die base 17 can be kept on the same straight line.

Referring to fig. 2, a guide bar 21 is disposed on a power base 13, a hollow groove 212 is formed in the middle of the guide bar 21, the hollow groove 212 is formed in the middle of the guide bar 21, so that the overall weight of the guide bar 21 can be reduced, and the guide bar 21 can be driven, the number of the guide bars 21 is determined according to circumstances, in the embodiment of the present application, two guide bars 21 are slidably connected to the power base 13, specifically, a locking column 22 is fixed between the power base 13 and an upper die base 11, the locking column 22 and the guide bar 21 are arranged in parallel, and one end of the guide bar 21 away from the upper die base 11 extends out of the power base 13, a transmission shaft is rotatably connected to the middle of the locking column 22, a transmission gear 221 is fixed to one end of the transmission shaft, a first driving motor 222 is disposed on one side of the locking column 22 away from the transmission gear 221, and the output end of the first driving motor 222 is assembled with the transmission shaft correspondingly, a rack 211 is fixed on one side of the guide bar 21 close to the transmission gear 221, the rack 211 and the guide bar 21 are fixed in a welding mode, and the transmission gear 221 and the rack 211 are meshed.

Under the action of the first driving motor 222, the transmission shaft can rotate, so that the transmission gear 221 fixed on the transmission shaft also rotates, and the guide bar 21 moves in the vertical direction.

In order to further improve the stability of the guide strips 21 in the movement process, referring to fig. 2, the two guide strips 21 are symmetrically arranged on the same long edge of the power seat 13 along the central axis of the power seat 13, so that the guide strips 21 are respectively arranged at two corners of the same long edge of the power seat 13, correspondingly, a matching column 24 is arranged on the other long edge of the power seat 13, the number of the matching columns 24 is two, and the two matching columns 24 are respectively fixed at two corners of the same long edge of the power seat 13, so that the matching columns 24 and the locking columns 22 are arranged in a right-to-left manner.

The position department sliding connection that is close to cooperation post 24 at power seat 13 has spacing 23, in the embodiment of this application, the shape and size of spacing 23 is unanimous with the shape and size of gib block 21, spacing 23 parallels to lay between gib block 21, the outer wall welding of spacing 23 has cooperation piece 231, cooperation post 24 is close to one side of cooperation piece 231 and has been seted up guide slot 241, the extending direction of guide slot 241 is unanimous with the extending direction of cooperation post 24, looks adaptation sliding connection between cooperation piece 231 and the guide slot 241, in addition, be provided with fixed frame 25 at the top of power seat 13, fixed frame 25 respectively with gib block 21, spacing 23 carries out bolted connection, namely, make gib block 21, spacing 23 fixed with fixed frame 25 mutually.

When first driving motor 222 drives gib block 21 to move in the vertical direction, under the cooperation of fixed frame 25, cooperation block 231 can slide on guide slot 241, and then drives spacing strip 23 to move in the vertical direction as well, is favorable to reducing gib block 21, spacing strip 23 and the skew phenomenon appears in the motion process.

The base 1 further includes a flared seat 14, referring to fig. 2 and 3, the flared seat 14 is disposed at the bottom of the power seat 13, and a transmission rod 32 is disposed between the flared seat 14 and the upper die base 11, in this embodiment, the transmission rod 32 is a ball screw, one end of the transmission rod 32 is in threaded connection with the flared seat 14, and the other end of the transmission rod 32 is rotatably connected with the upper die base 11, a second driving motor 31 is disposed at a position of the upper die base 11 close to the transmission rod 32, an output end of the second driving motor 31 is assembled with the transmission rod 32, and the transmission rod 32 can rotate under the driving of the second driving motor 31, so that the flared seat 14 can move in the vertical direction.

In addition, be provided with the expander roll group on flaring seat 14, the expander roll group is including a plurality of expander rolls 4, and parallel arrangement between a plurality of expander rolls 4 carries out fixed connection between expander roll 4 and the flaring seat 14, and when second driving motor 31 drive flaring seat 14 was the ascending motion of vertical direction, a plurality of expander rolls 4 also can be the ascending motion of vertical direction simultaneously.

In the embodiment of the present application, the expansion rod 4 includes a connecting rod 41, a flanging convex block 42, a flaring block 43, and a stop block 45, referring to fig. 3, the connecting rod 41, the flanging convex block 42, the flaring block 43, and the stop block 45 are integrally formed, the connecting rod 41 is a circular rod body, the connecting rod 41 is fixed on the flaring seat 14, and one end of the connecting rod 41 away from the lower die seat 17 is slidably connected with the power seat 13, the section of the flanging convex block 42 is triangular, the flanging convex block 42 is arranged at one end of the connecting rod 41 close to the limiting seat 15, the small end of the flanging convex block 42 is arranged at the extreme end of the connecting rod 41, the flaring block 43 is a circular block, the flaring block 43 is fixed on the top surface of the connecting rod 41 close to the flanging convex block 42, the stop block 45 is also a circular block, the stop block 45 is fixed on the top surface of the connecting rod 41 close to the flaring block 43, and the diameter of the stop block 45 is larger than that of the flaring block 43, and an arc-shaped connecting part 44 is arranged between the flanging convex block 42 and the flaring block 43, and the arc-shaped connecting part 44 is in smooth transition with the flanging convex block 42 and the flaring block 43 respectively.

Referring to fig. 4, a limiting seat 15 is arranged at the top of a lower die holder 17, a finned heat exchanger 7 is slidably connected to the middle of the limiting seat 15, the finned heat exchanger 7 comprises an installation frame and a finned tube group, the finned tube group is arranged in the middle of the installation frame and comprises a plurality of finned tubes, in the embodiment of the application, the number of the finned rods is consistent with the number of the expansion rods 4, the expansion rods 4 and the finned tubes are arranged in a one-to-one manner, the guide strips 21 are arranged in a manner of being opposite to the top surface of one side edge of the installation frame, and the limiting strips 23 are arranged in a manner of being opposite to the top surface of the other side edge of the installation frame.

Fixing base 61 is installed to the top surface of die holder 17, and spacing seat 15 sets up the one side that is close to die holder 17 at fixing base 61, and parallel arrangement between spacing seat 15 and the die holder 17, spout 611 has been seted up respectively to the relative lateral wall of fixing base 61, and spout 611 sets up on the minor face inside wall of fixing base 61, correspondingly, connecting block 62 is installed to the lateral wall of installing frame, looks adaptation sliding connection between connecting block 62 and the spout 611.

The middle part of the limiting seat 15 is provided with a through slot 63, the finned heat exchanger 7 is in sliding connection with the through slot 63, the inner bottom wall of the limiting seat 15 is provided with a damping layer 64, the bottom wall of the finned tube group is abutted against the damping layer 64, wherein the damping layer 64 comprises a damping plate and a damping spring, the section size of the damping plate is matched with the section size of the through slot 63, one end of the damping spring is assembled with the inner bottom wall of the limiting seat 15, the other end of the damping spring is assembled with the bottom wall of the damping plate, a damping cavity is formed between the damping plate and the limiting seat 15, noise pollution when the expansion rod 4 expands the tube is reduced, meanwhile, the phenomenon that the finned tube directly collides with the inner bottom wall of the limiting seat 15 is reduced, in addition, a wear-resistant gasket 65 is arranged at the position of the input end of the limiting seat 15, the wear-resistant gasket 65 is a rubber gasket, and the wear-resistant gasket 65 is fixed with the limiting seat 15 in a glue bonding mode, the finned tube group can be protected to a certain extent.

The implementation principle of the pipe expander in the embodiment of the application is as follows:

the staff first connects the fin heat exchanger 7 in the fixing base 61 in a sliding manner, namely, the connecting slide block 62 slides with the sliding groove 611, the bottom of the fin heat exchanger 7 slides with the limiting base 15, and then the guide column 12 is inserted in the mounting column 16 in a sliding manner.

Under the effect of first driving motor 222, the transmission shaft can rotate, makes the drive gear 221 who fixes on the transmission shaft also rotate, and under the mating reaction of fixed frame 25, vertical decurrent motion is done simultaneously to gib block 21, spacing 23, and cooperation piece 231 slides with guide slot 241 mutually, and then makes gib block 21, spacing 23 support simultaneously and press on the top surface of installing frame, accomplishes the location to finned heat exchanger 7.

Under the drive of second driving motor 31, transfer line 32 can rotate, and flaring seat 14 drives the expander roll 4 and is vertical downward motion simultaneously, makes expander roll 4 alternate in the middle part of finned tube, and the bottom of finned tube supports with the top surface of shock attenuation board mutually and presses, accomplishes the expand tube to the finned tube.

Example 2:

the present embodiment is different from embodiment 1 in the structure of the expander rod 4.

Referring to fig. 4 and 5, the expansion rod 4 includes a fixing rod 51 and a flanging module 52, in this embodiment, the fixing rod 51 is a circular rod, the flanging module 52 is a triangular block, the fixing rod 51 and the flanging module 52 are integrally formed, and the connecting portion between the fixing rod 51 and the flanging module 52 is smoothly transitioned, when the end of the finned tube needs to be flanged, the fixing rod 51 is installed on the flaring seat 14, and the small end of the flanging module 52 faces the middle of the finned tube, the transmission rod 32 can rotate under the driving of the second driving motor 31, the flaring seat 14 drives the expansion rod 4 to move vertically and downwards at the same time, so that the expansion rod 4 is inserted into the middle of the finned tube, the bottom of the finned tube is pressed against the top surface of the damping plate, and the end flanging of the finned tube is completed.

The above are all preferred embodiments of the present application, and the present embodiment is only explained for the present application, and the protection scope of the present application is not limited by this, so: equivalent changes in structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims

1. The tube expander comprises a machine base (1) and is characterized in that the machine base (1) comprises a power base (13), a flaring base (14) and a limiting base (15), a guide strip (21) is installed on the power base (13), the top of the power base (13) is provided with a positioning transmission assembly used for driving the guide strip (21) to move in the vertical direction, the middle of the limiting base (15) is slidably connected with a fin heat exchanger (7), the fin heat exchanger (7) comprises an installation frame and a fin tube group, the fin tube group is arranged in the middle of the installation frame, the guide strip (21) and the installation frame are arranged oppositely, the middle of the flaring base (14) is provided with a transmission rod (32), the transmission rod (32) is provided with a driving piece used for driving the flaring base (14) to move in the vertical direction, an expansion rod group is fixed on the flaring seat (14), and the expansion rod group and the fin tube group are arranged in a right-to-right mode.

2. A tube expander as claimed in claim 1, wherein said set of expansion rods comprises a plurality of expansion rods (4), said expansion rods (4) comprising: a connecting rod (41) mounted on the flaring seat (14); the flanging lug (42) is fixed at one end, close to the limiting seat (15), of the connecting rod (41); the flaring block (43) is fixed on the connecting rod (41) and is close to the top surface of the flanging convex block (42); and the stop block (45) is arranged on the connecting rod (41) close to the top surface of the flaring block (43), wherein the diameter size of the stop block (45) is larger than that of the flaring block (43).

3. The pipe expander according to claim 2, wherein an arc-shaped joint (44) is formed between the flanging lug (42) and the flaring block (43), and the arc-shaped joint (44) is in smooth transition with the flanging lug (42) and the flaring block (43), respectively.

4. The pipe expander of claim 1, wherein the positioning transmission assembly comprises: a locking column (22) fixed on the top surface of the power seat (13); a transmission shaft rotatably connected to the middle part of the locking column (22); a transmission gear (221) installed at one end of the transmission shaft; the locking device comprises a rack (211) arranged on one side, close to a transmission gear (221), of the guide bar (21), and a first driving motor (222) installed on the side wall of the locking column (22), wherein the output end of the first driving motor (222) is assembled with the transmission shaft, and the transmission gear (221) is meshed with the rack (211).

5. The pipe expander according to claim 4, wherein a hollow groove (212) is formed through the middle of the guide strip (21).

6. The pipe expander according to claim 1, wherein an upper die holder (11) is mounted at the top of the power seat (13), a guide column (12) is arranged between the upper die holder (11) and the power seat (13), a lower die holder (17) is arranged at the bottom of the limiting seat (15), a mounting column (16) is arranged on the top surface of the lower die holder (17), and the part of the guide column (12) penetrating out of the power seat (13) is slidably connected with the mounting column (16).

7. The pipe expander according to claim 6, wherein the top wall of the upper die holder (11) is provided with a second driving motor (31), the output end of the second driving motor (31) is assembled with the transmission rod (32), one end of the transmission rod (32) is in threaded connection with the flaring seat (14), and the other end is in rotational connection with the upper die holder (11).

8. The pipe expander according to claim 6, wherein a fixed seat (61) is installed on the top surface of the lower die seat (17), the limiting seat (15) is arranged on one side of the fixed seat (61) close to the lower die seat (17), sliding grooves (611) are respectively formed in two opposite side walls of the fixed seat (61), a connecting sliding block (62) is installed on the side wall of the installation frame, and the connecting sliding block (62) is in sliding connection with the sliding grooves (611) in a matching manner.

9. The pipe expander according to claim 1, wherein a through slot (63) is formed in the middle of the limiting seat (15), the fin heat exchanger (7) is slidably connected with the through slot (63), a damping layer (64) is arranged on the inner bottom wall of the limiting seat (15), and the bottom wall of the fin pipe group abuts against the damping layer (64).

10. A tube expander as claimed in claim 9, characterised in that a wear washer (65) is provided at the location of the input end of the seat (15).