A high-efficiency automatic turning machine for finned tubes of heat exchange equipment

Abstract

The application discloses a high-efficiency automatic turning machine for finned tube of heat exchange equipment and relates to the technical field of turning equipment. The application discloses a high-efficiency automatic turning machine for finned tube of heat exchange equipment and relates to the technical field of turning equipment. The upper end of the base is fixedly provided with a pushing feeding mechanism on the front side, the upper end of the base is fixedly provided with a material transferring mechanism on the rear side of the pushing feeding mechanism, the upper end of the base is further fixedly provided with a turning processing mechanism arranged on the outer side of the material transferring mechanism, and the upper end of the base is further fixedly provided with a material supporting mechanism arranged on the inner side of the turning processing mechanism and corresponding to the material transferring mechanism. The length of the base pipe can be synchronously detected, the inner supporting clamping force of the inner supporting clamping mechanism can be automatically controlled based on the length of the base pipe, the stability of subsequent processing of the base pipe is ensured, and the base pipe inner wall indentation or local deformation caused by excessive inner supporting is avoided.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of turning equipment, in particular to a high-efficiency automatic turning machine for finned tube of heat exchange equipment. BACKGROUND

[0002] The finned tube, also known as a heat exchange tube, is a heat exchange element for heat transfer enhancement. By adding fins outside the smooth base tube, the heat exchange area can be increased by 3-10 times, directly determining the energy efficiency of the heat exchange equipment. The finned tube processing needs to use a turning machine, which processes annular fins on the outer surface of the metal base tube through a turning process.

[0003] At present, in the turning processing of the finned tube, the processing mode of "fixed base tube rotation speed (main shaft rotation speed) and tool head feed speed" is still adopted in most scenarios, but this mode does not consider the core influence of the length change of the base tube on the processing stability - the rigidity of the base tube is inversely proportional to the length. The short tube (usually <1.5m) has strong rigidity, and the ability to resist centrifugal force and cutting force is better during processing. The rigidity of the long tube (usually >2m) is greatly weakened, and it is easy to bend and vibrate (chatter) due to external force. If the fixed parameters are always used, it will cause targeted problems to the processing quality of finned tubes of different lengths, which is specifically shown as follows:

[0004] For long tube processing, the fixed high rotation speed will make the centrifugal force of the base tube rotation (increasing with the square of the rotation speed) far exceed its rigidity bearing limit, causing the base tube to "swing" or resonate, and further causing the fin height deviation to exceed ±0.05mm, and even the bending deformation of the middle section of the base tube (roundness error >0.1mm); at the same time, the fixed high feed speed will increase the cutting force per unit time (positively related to the feed speed), further intensifying the radial bending of the long tube, causing the fin root to not fit tightly with the base tube, and in severe cases, the fin may crack and the edge burr may exceed the standard (Ra>3.2μm).

[0005] For short tube processing, if the low fixed rotation speed and feed speed suitable for long tube are used, it will cause waste of equipment performance - the short tube itself has enough rigidity to withstand higher parameters, and the fixed low rotation speed will prolong the processing cycle of a single tube (30%-40% slower than the optimal parameter), and the fixed low feed speed will reduce the batch production efficiency, which cannot fully utilize the high processing capacity of the equipment.

[0006] In summary, this "one-size-fits-all" fixed parameter mode will cause unstable processing quality of long tubes (waste rate exceeding 2%) and low processing efficiency of short tubes, which cannot meet the quality requirements of high-precision finned tubes (such as finned tubes for heat exchange equipment, which require fin height tolerance ≤±0.03mm), and is difficult to adapt to the flexible production needs of finned tubes of different lengths. SUMMARY

[0007] In view of the problems existing in the prior art, the present application is proposed.

[0008] Therefore, the present application aims to provide a high-efficiency automatic turning machine for finned tube of heat exchange equipment, which solves the problem of fixed machining parameters in traditional finned tube machining, which cannot be self-adapted according to the length of the base tube, resulting in damage to the longer base tube and affecting the turning quality.

[0009] In order to achieve the above-mentioned purpose, the present application provides the following technical scheme: a high-efficiency automatic turning machine for finned tube of heat exchange equipment, comprising a base and a PLC controller fixedly arranged at the rear side of the upper end of the base, a push-up feeding mechanism fixedly arranged at the front side of the upper end of the base, a material transfer mechanism fixedly arranged at the rear side of the push-up feeding mechanism, a turning machining mechanism fixedly arranged at the upper end of the base and located outside the material transfer mechanism, and a material supporting mechanism fixedly arranged at the inner side of the turning machining mechanism and corresponding to the material transfer mechanism, wherein the PLC controller is electrically connected with the push-up feeding mechanism, the material transfer mechanism and the turning machining mechanism.

[0010] As a preferred scheme of the high-efficiency automatic turning machine for finned tube of heat exchange equipment, wherein:

[0011] The push-up feeding mechanism comprises two symmetrical support columns fixedly arranged at the upper end of the base, a same storage shell fixedly connected with the upper ends of the two support columns, the upper end of the storage shell being open and the two sides being provided with strip-shaped openings, and two first electric push rods fixedly inserted into the bottom of the storage shell, the upper end output ends of the two first electric push rods extending into the storage shell and being fixedly connected with a same material pushing plate.

[0012] As a preferred scheme of the high-efficiency automatic turning machine for finned tube of heat exchange equipment, wherein:

[0013] The material transfer mechanism comprises two longitudinal electric sliding rails fixedly arranged at the upper end of the base, a second electric push rod fixedly connected with the upper end of the sliding block in the longitudinal electric sliding rail, a same lifting plate fixedly connected with the upper end moving end of the second electric push rod, a bidirectional electric sliding rail fixedly connected with the front side of the lifting plate, an extension plate fixedly connected with the moving end of each side of the bidirectional electric sliding rail, an inner supporting clamping mechanism fixedly connected with one end of each of the two extension plates away from the bidirectional electric sliding rail, and an infrared emitter and an infrared receiver fixedly arranged at the opposite side wall of each of the two extension plates.

[0014] As a preferred scheme of the high-efficiency automatic turning machine for finned tube of heat exchange equipment, wherein:

[0015] The turning mechanism comprises a U-shaped support fixedly arranged on the upper end of the base, the upper end of the U-shaped support is symmetrically fixed with two third electric push rods, the lower ends of the two third electric push rods are fixedly connected with the same extrusion plate, the lower side of the extrusion plate is fixedly connected with a plurality of turning tool heads, and the turning tool heads are located directly above the supporting mechanism.

[0016] As a preferred scheme of the high-efficiency automatic turning machine tool for the finned tube of the heat exchange equipment,

[0017] The two symmetrical columns are fixedly connected to the upper end of the base, and the upper ends of the two columns are fixedly connected with the same arc-shaped supporting plate.

[0018] As a preferred scheme of the high-efficiency automatic turning machine tool for the finned tube of the heat exchange equipment,

[0019] The inner support clamping mechanism comprises a transmission shaft rotatably connected to the side wall of the extension plate, a servo motor is fixedly arranged on the outer wall of the extension plate and used for driving the rotation of the transmission shaft, a plurality of micro electric push rods are fixedly connected to the shaft wall of the transmission shaft in a symmetrical manner, and the same arc-shaped inner support plate is fixedly connected to the moving ends of the two micro electric push rods on the same side.

[0020] As a preferred scheme of the high-efficiency automatic turning machine tool for the finned tube of the heat exchange equipment,

[0021] The inner side top of the U-shaped support is further fixedly arranged with a plurality of micro laser range finders located at the rear side of the turning tool head, and the plurality of micro laser range finders are correspondingly arranged with the plurality of turning tool heads.

[0022] As a preferred scheme of the high-efficiency automatic turning machine tool for the finned tube of the heat exchange equipment,

[0023] The width of the strip-shaped opening of the storage shell is the same as the outer diameter size of the base pipe to be processed, so that the base pipe can stably move up and down in the storage shell.

[0024] In summary, the present application has at least one of the following beneficial effects:

[0025] 1、The present application, through the cooperation of the push-up feeding mechanism, the material transferring mechanism, the material supporting mechanism and the inner support clamping mechanism, can quickly move the base pipe to be processed to the processing position, and can simultaneously detect the length of the base pipe, and automatically control the inner support clamping force of the inner support clamping mechanism based on the length of the base pipe, so as to ensure the stability of the subsequent processing of the base pipe, and also avoid excessive inner support which may cause indentation or local deformation of the inner wall of the base pipe.

[0026] 2、The application can process the base pipe surface synchronously and quickly through the processing operation of the turning processing mechanism, effectively improves the production efficiency of the finned tube, and can automatically control the turning feed speed based on the length of the base pipe, the feed speed decreases with the increase of the length of the base pipe, avoids the problem that long base pipes are weak in rigidity and cannot bear large cutting force, and are prone to bending deformation.

[0027] 3、The application can quickly detect the processing quality after processing through the work of the miniature laser range finder, can synchronously feed back the wear problem of the turning tool bit, timely feeds back information to remind the staff to make corresponding processing, and ensures the quality of continuous production and processing. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments will be briefly introduced. Obviously, the drawings in the following description are only some embodiments described in the present application, and other drawings can also be obtained by those skilled in the art according to these drawings.

[0029] Figure 1 It is a front view of the structure of the application.

[0030] Figure 2 It is a rear view of the structure of the application.

[0031] Figure 3 It is a sectional view of the structure of the application.

[0032] Figure 4 It is a sectional view of the structure of the application.

[0033] Figure 5 It is a sectional view of the structure of the application.

[0034] Figure 6 It is a sectional view of the structure of the application.

[0035] Figure 7 It is a sectional view of the structure of the application.

[0036] Explanation of reference signs:

[0037] 1, base; 2, push feeding mechanism; 21, support column; 22, storage shell; 23, strip-shaped opening; 24, first electric push rod; 25, feeding plate; 3, material transfer mechanism; 31, longitudinal electric slide rail; 32, second electric push rod; 33, lifting plate; 34, bidirectional electric slide rail; 35, extension plate; 36, infrared emitter; 37, infrared receiver; 4, turning processing mechanism; 41, U-shaped support; 42, third electric push rod; 43, extrusion plate; 44, turning tool bit; 45, miniature laser range finder; 5, material supporting mechanism; 51, vertical column; 52, arc-shaped supporting plate; 6, inner support clamping mechanism; 61, transmission shaft; 62, servo motor; 63, miniature electric push rod; 64, arc-shaped inner support plate; 7, PLC controller. DETAILED DESCRIPTION

[0038] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0039] The present application discloses a high-efficiency automatic turning machine tool for finned tube of heat exchange equipment.

[0040] Embodiment 1

[0041] Reference Figures 1-7 The present application discloses a high-efficiency automatic turning machine tool for finned tube of heat exchange equipment, which comprises a base 1 and a PLC controller 7 fixedly arranged on the rear side of the upper end of the base 1. A push feeding mechanism 2 is fixedly arranged on the front side of the upper end of the base 1. The push feeding mechanism 2 comprises two symmetrical support columns 21 fixedly arranged on the upper end of the base 1. The upper ends of the two support columns 21 are fixedly connected with the same storage shell 22. The upper end of the storage shell 22 is open, and strip-shaped openings 23 are formed on both sides. Two first electric push rods 24 are fixedly inserted into the bottom of the storage shell 22. The upper end output ends of the two first electric push rods 24 extend into the storage shell 22 and are fixedly connected with the same feeding plate 25. The width of the storage shell 22 corresponding to the strip-shaped opening 23 is the same as the outer diameter size of the base pipe to be processed, so that the base pipe can move up and down stably in the storage shell 22.

[0042] The upper end of the base 1 is fixedly provided with a material transferring mechanism 3 located at the rear side of the push-feeding mechanism 2. The material transferring mechanism 3 comprises two symmetrical longitudinal electric sliding rails 31 fixedly provided at the upper end of the base 1. The upper end of the sliding block in the longitudinal electric sliding rail 31 is fixedly connected with a second electric push rod 32. The upper end of the two second electric push rods 32 is fixedly connected with the same lifting plate 33. The front side of the lifting plate 33 is fixedly connected with a bidirectional electric sliding rail 34. The moving end of the bidirectional electric sliding rail 34 located at both sides is fixedly connected with an extension plate 35. The extension plate 35 is fixedly connected with an inner supporting and clamping mechanism 6 away from the bidirectional electric sliding rail 34. The extension plate 35 is fixedly provided with an infrared emitter 36 and an infrared receiver 37 on the opposite side wall.

[0043] The upper end of the base 1 is also fixedly provided with a turning machining mechanism 4 arranged outside the material transferring mechanism 3. The turning machining mechanism 4 comprises a U-shaped support 41 fixedly provided at the upper end of the base 1. The upper end of the U-shaped support 41 is symmetrically fixedly sleeved with two third electric push rods 42. The lower end of the two third electric push rods 42 is fixedly connected with the same extrusion plate 43. The lower side of the extrusion plate 43 is equidistantly fixedly connected with a plurality of turning tool bits 44. The turning tool bits 44 are located directly above the supporting mechanism. The inner side top of the U-shaped support 41 is also fixedly provided with a plurality of miniature laser range finders 45 located at the rear side of the turning tool bits 44. The plurality of miniature laser range finders 45 are arranged in position correspondence with the plurality of turning tool bits 44.

[0044] The upper end of the base 1 is also fixedly provided with a material supporting mechanism 5 located inside the turning machining mechanism 4 and arranged in position correspondence with the material transferring mechanism 3. The material supporting mechanism comprises two symmetrical vertical columns 51 fixedly connected at the upper end of the base 1. The upper end of the two vertical columns 51 is fixedly connected with the same arc-shaped supporting plate 52.

[0045] The inner supporting and clamping mechanism 6 comprises a transmission shaft 61 rotatably connected with the side wall of the extension plate 35. The outer wall of the extension plate 35 is fixedly provided with a servo motor 62 for driving the self-rotation of the transmission shaft 61. The shaft wall of the transmission shaft 61 is symmetrically fixedly connected with a plurality of miniature electric push rods 63. The moving end of the two miniature electric push rods 63 located at the same side is fixedly connected with the same arc-shaped inner supporting plate 64.

[0046] The PLC controller 7 is electrically connected with the push-feeding mechanism 2, the material transferring mechanism 3 and the turning machining mechanism 4 respectively.

[0047] When turning machining is needed, a plurality of base pipes to be machined are placed in the storage shell 22. The two ends of the base pipes are stretched out of the storage shell 22 through the strip-shaped through opening 23 formed in the side wall of the storage shell 22. The PLC controller 7 controls the first electric push rod 24 to push the top plate 25 to move upward by a fixed height. The upward moving height is equal to the outer diameter of the base pipe, thereby ensuring that the uppermost base pipe is at a fixed height position.

[0048] PLC controller 7 controls the material transfer mechanism 3 to act, the longitudinal electric slide rail 31 drives longitudinally, and the bidirectional electric slide rail 34 and the extension plate 35 move to the material taking position. At this time, the two extension plates 35 move to the two sides of the base pipe, the bidirectional electric slide rail 34 drives the two extension plates 35 to move towards each other, and then the extension plates 35 move towards the base pipe until the two extension plates 35 are clamped at the two ends of the base pipe, and the load pressure feedback by the bidirectional electric slide rail 34 reaches the threshold value. At this time, the PLC controller 7 controls the bidirectional electric slide rail 34 to stop acting, and the inner support clamping mechanism 6 also moves to the inner side of the base pipe. The PLC controller 7 controls the micro electric push rod 63 in the inner support clamping mechanism 6 to act, the micro electric push rod 63 pushes the arc-shaped inner support plate 64 to move outward, and a plurality of arc-shaped inner support plates 64 abut against the inner wall of the base pipe to achieve clamping and fixing of the base pipe. After the extension plate 35 moves to the position, the PLC controller 7 controls the infrared emitter 36 and the infrared receiver 37 on the two extension plates 35 to work, and then the distance between the two extension plates 35 is confirmed, which represents the length of the base pipe. The PLC controller 7 adjusts the threshold value of the output pressure of the micro electric push rod based on the length information of the base pipe fed back. Specifically, the longer the length of the base pipe is, the greater the pressure threshold value of the micro electric push rod 63 controlled by the PLC controller 7 is, that is, the arc-shaped inner support plate 64 generates greater inner support force with the base pipe, and the base pipe is clamped and fixed with greater strength. Because the shorter base pipe has strong rigidity, only moderate inner support force is needed to ensure stable clamping (to avoid the base pipe slipping in rotation), and excessive inner support force will cause indentation or local deformation of the inner wall of the base pipe. For the longer base pipe, the rigidity is weak, and if the inner support force is insufficient, the base pipe will move radially or axially due to centrifugal force and cutting force in rotation. Therefore, the clamping stability needs to be improved by increasing the inner support force to offset the centrifugal force in rotation and the radial force in cutting, and to suppress the vibration of the base pipe.

[0049] The PLC controller 7 controls the second electric push rod 32 and the longitudinal electric slide rail 31 to act, moves the clamped base pipe to the material supporting mechanism 5, and places the base pipe on the arc-shaped supporting plate 52 to complete the limiting placement of the base pipe.

[0050] The PLC controller 7 adjusts the working power of the servo motor 62 based on the length of the base pipe. Specifically, the longer the length of the base pipe is, the slower the speed of the servo motor 62 controlled by the PLC controller 7 is, and the slower the synchronous rotation speed of the base pipe driven by the inner support clamping mechanism 6 is. Because under the action of centrifugal force, the higher the rotation speed of the base pipe is, the greater the centrifugal force (F=mrω², ω is the angular velocity) of the base pipe in rotation is. The short base pipe has strong rigidity and can withstand, but the long base pipe will be bent due to centrifugal force, resulting in radial position deviation of the fin in processing (such as the height of the fin being higher on one side and lower on the other side). Therefore, with the increase of the length of the base pipe, the rotation cutting speed needs to be reduced.

[0051] The PLC controller 7 controls the turning mechanism 4 to act, and the third electric push rod 42 pushes the extrusion plate 43 and the plurality of turning tool heads 44 to move downward, so that the turning tool heads 44 gradually contact the outer surface of the base pipe, and then the fins on the outer surface of the base pipe are turned out, and the PLC controller 7 also automatically controls the turning feed speed of the third electric push rod 42 pushing the turning tool heads 44 based on the length of the base pipe. The longer the length of the base pipe, the slower the turning feed speed, because the feed speed determines the axial movement distance of the tool per unit time, and the core influence is the cutting force. The faster the feed speed, the greater the cutting amount per revolution, and the greater the radial cutting force of the tool on the base pipe. The long base pipe is weak in rigidity and cannot withstand large cutting force, and is prone to bending deformation. Therefore, it is necessary to reduce the feed speed to ensure the stability of turning;

[0052] After the turning is completed, the PLC controller 7 controls the turning mechanism 4 to reset, and then moves the processed base pipe to the position directly below the plurality of micro laser range finders 45 in the turning mechanism 4 through the material conveying mechanism 3. The distance between the base pipe surface and the turning groove is detected by the micro laser range finder 45 to confirm whether the turning work is qualified. When the unqualified turning depth causes the inconsistent height of the fins, the positioning module in the micro laser range finder 45 feeds back the positioning information to the staff to confirm the position of the specific turning tool head 44 that has a problem, so that the staff can quickly check. When three tool heads are worn out beyond the standard in the same shift, the cutting parameters are checked based on the feedback suggestion.

[0053] When 4-6 tool heads are detected to be worn out beyond the standard within 2 hours, the machine tool pauses the current batch processing and switches to the maintenance mode, retains the on-site data (such as cutting parameters and base pipe batch number), and automatically pushes a work order to the system, requiring: replacing the tool heads that are worn out beyond the standard; checking the concentration of cutting fluid (which may cause batch wear due to insufficient lubrication); and calibrating the laser detection system (to avoid systematic misjudgment).

[0054] When >6 tool heads are worn out beyond the standard in the same shift, or the tool wear amount is detected to increase by >20% in a ring comparison for three times in a row, the whole line is stopped and the program is locked to prevent further processing; the system automatically sends a message to the equipment supervisor, the content of which includes 12 tool heads worn out beyond the standard (the average value of VB is 0.38 mm), and it is suggested to check the batch quality of the tool supplier; the whole process is started to be traced back: the data such as base pipe batch, cutting parameters, and tool batch are associated, and the root cause (such as tool material defect and abnormal spindle speed) is analyzed through a machine learning model.

[0055] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and not to limit the present application. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced equivalently without departing from the spirit and scope of the present application, and all should be covered in the scope of the claims of the present application.

Claims

1. A high-efficiency automatic turning machine for finned tubes in heat exchange equipment, characterized in that: The base (1) and the PLC controller (7) fixedly arranged on the rear side of the upper end of the base (1), the top pushing and feeding mechanism (2) fixedly arranged on the front side of the upper end of the base (1), the material transferring mechanism (3) fixedly arranged on the rear side of the top pushing and feeding mechanism (2) of the upper end of the base (1), the turning mechanism (4) fixedly arranged on the outside of the material transferring mechanism (3) of the upper end of the base (1), the material supporting mechanism (5) fixedly arranged on the inside of the turning mechanism (4) of the upper end of the base (1) and corresponding to the material transferring mechanism (3), and the PLC controller (7) electrically connected with the top pushing and feeding mechanism (2), the material transferring mechanism (3) and the turning mechanism (4); The top pushing and feeding mechanism (2) comprises two symmetrical support columns (21) fixedly arranged on the upper end of the base (1), the upper ends of the two support columns (21) are fixedly connected with the same storage shell (22), the upper end of the storage shell (22) is opened, strip-shaped openings (23) are formed on both sides of the storage shell (22), and the bottom of the storage shell (22) is fixedly sleeved with two first electric push rods (24); the upper end output ends of the two first electric push rods (24) extend into the storage shell (22) and are fixedly connected with the same material pushing plate (25); The material transferring mechanism (3) comprises two symmetrical longitudinal electric sliding rails (31) fixedly arranged on the upper end of the base (1), the upper end of the sliding block in the longitudinal electric sliding rail (31) is fixedly connected with a second electric push rod (32), the upper end moving end of the second electric push rod (32) is fixedly connected with the same lifting plate (33), the front side of the lifting plate (33) is fixedly connected with a bidirectional electric sliding rail (34), the moving ends of the bidirectional electric sliding rail (34) on both sides are fixedly connected with extension plates (35), the ends, away from the bidirectional electric sliding rail (34), of the two extension plates (35) are fixedly connected with inner support clamping mechanisms (6), and infrared emitters (36) and infrared receivers (37) are fixedly arranged on the opposite side walls of the two extension plates (35); The inner support clamping mechanism (6) comprises a transmission shaft (61) rotatably connected to the side wall of the extension plate (35), a servo motor (62) is fixedly arranged on the outer wall of the extension plate (35) and used for driving the rotation of the transmission shaft (61), a plurality of micro electric push rods (63) are fixedly connected to the shaft wall of the transmission shaft (61), and the moving ends of the two micro electric push rods (63) on the same side are fixedly connected with the same arc-shaped inner support plate (64); The turning mechanism (4) comprises a U-shaped support (41) fixedly arranged on the upper end of the base (1), two third electric push rods (42) are fixedly sleeved on the upper end of the U-shaped support (41) in a symmetrical mode, the lower end moving end of the third electric push rod (42) is fixedly connected with the same extrusion plate (43), a plurality of turning tool heads (44) are fixedly connected to the lower side of the extrusion plate (43) at equal intervals, and the turning tool heads (44) are located directly above the supporting mechanism. The inner side top of the U-shaped support (41) is further fixedly provided with a plurality of micro laser range finders (45) located at the rear side of the turning tool heads (44), and the plurality of micro laser range finders (45) are arranged in correspondence with the positions of the plurality of turning tool heads (44).

2. The heat exchanger finned tube high-efficiency automatic turning machine of claim 1, wherein, The material supporting mechanism comprises two vertical columns (51) fixedly connected to the upper end of the base (1), and the upper end of the two vertical columns (51) is fixedly connected with the same arc-shaped supporting plate (52).

3. The high efficient automatic turning machine for finned tube of heat exchange equipment according to claim 1, characterized in that, The width of the strip-shaped opening (23) corresponding to the storage shell (22) is the same as the outer diameter size of the base pipe to be processed, so that the base pipe moves stably up and down in the storage shell (22).

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