CN111398423A

CN111398423A - Ultrasonic nondestructive testing device for shaft parts

Info

Publication number: CN111398423A
Application number: CN202010356296.6A
Authority: CN
Inventors: 达刚; 季建华; 姜振祥; 王英锋
Original assignee: Nantong Yinhe Measurement And Control Technology Co ltd
Current assignee: Nantong Yinhe Measurement And Control Technology Co ltd
Priority date: 2020-04-29
Filing date: 2020-04-29
Publication date: 2020-07-10

Abstract

The invention provides an ultrasonic nondestructive detection device for shaft parts, which comprises a detection workbench and a controller, wherein a coupling water tank and a cantilever beam unit are arranged on the detection workbench, a pair of parallel rolling shafts with the same diameter are arranged in the coupling water tank along the horizontal direction, two ends of each rolling shaft penetrate through the wall of the coupling water tank through a bearing and a sealing sleeve, a synchronous belt is connected between the rolling shafts, and the rolling shafts are driven by a speed reduction motor arranged outside the coupling water tank to rotate along the axial direction; the cantilever beam unit comprises a beam which is arranged above the water tank and is parallel to the driving rolling shaft, a probe lifting seat capable of moving horizontally is arranged on the beam, a probe frame capable of moving up and down is arranged on the probe lifting seat, and a plurality of ultrasonic probes are arranged on the probe frame. The flaw detection device is simple in structure, convenient to operate, low in surface smoothness requirement of a part to be detected, not prone to abrasion of the probe, modular in design of the probe set, convenient to assemble, disassemble and replace and suitable for nondestructive testing of shaft parts of various specifications.

Description

Ultrasonic nondestructive testing device for shaft parts

Technical Field

The invention belongs to the technical field of nondestructive inspection equipment, and particularly relates to an ultrasonic nondestructive inspection device for shaft parts.

Background

When the shaft parts are applied to equipment and workpieces, the shaft parts generally need to bear larger load, torque and the like, if the shaft parts have processing defects such as cracks, internal shrinkage cavities and the like, the problems of deformation, shaft breakage and the like are easy to occur in the using process, equipment damage or safety accidents are caused, and therefore, most of the shaft parts need to be subjected to a link of nondestructive inspection in the processing process. At present, the detection means which is commonly used is ultrasonic detection, and the internal defects of the material are detected by detecting the ultrasonic propagation waveform and the energy change during reflection and penetration by using the acoustic performance difference of the material and the defects thereof. The traditional ultrasonic nondestructive testing mode generally uses handheld flaw detection equipment, and is low in detection efficiency and high in labor cost by manually selecting points and probing and scanning parts to be tested, and especially for some parts with large batch processing quantity, the requirement of efficient production operation is difficult to meet by using the handheld equipment to detect flaws.

At present, some automatic detection equipment also appear in the field of nondestructive inspection of shaft parts, but the automatic detection equipment has the defects of complex structure, inconvenience in operation, high requirement on the surface machining precision of a part to be detected and the like. For example, in the axle radial automatic flaw detection device with the publication number CN103217477, an axle to be detected is supported and rotated by pneumatic centers at two ends, the coaxiality between the axle and the pneumatic centers is required to be ensured, the operation requirement is high, the equipment structure is more complicated, when the detection operation is carried out, a probe needs to be tightly attached to the surface of the axle, the requirement on the surface smoothness of the axle is high, and the probe is easy to wear. The axle automatic ultrasonic flaw detection device for the rail transit, with the publication number of CN101614703B, has a complex structure of an underwater supporting rotating mechanism, is easy to influence the smoothness of flaw detection signals, a plurality of groups of probes are controlled by servo motors respectively to keep the distance from the surface of the axle, the system linkage is complex, faults are easy to occur, and the cost is high.

Disclosure of Invention

Compared with the existing shaft flaw detection device, the shaft ultrasonic nondestructive detection device provided by the invention has the advantages that the structure of the supporting and rotating mechanism is simpler, the flaw detection operation is simpler and more convenient, and the flaw detection effect is better. In order to achieve the technical purpose, the technical scheme adopted by the invention is as follows:

an ultrasonic nondestructive detection device for shaft parts comprises a detection workbench and a controller, wherein a coupling water tank and a cantilever beam unit are arranged on the detection workbench; a pair of parallel rolling shafts with the same diameter are arranged in the coupling water tank along the horizontal direction, the rolling shafts are all arranged on the tank wall of the coupling water tank in a penetrating manner, and a bearing and a sealing sleeve are arranged at the joint of the rolling shafts and the tank wall; a synchronous belt is connected between the rollers at a position outside the coupling water tank; the rolling shafts comprise driving rolling shafts and driven rolling shafts, wherein the driving rolling shafts are driven by a speed reducing motor arranged on the detection workbench to rotate along the axial direction, and the driven rolling shafts are driven by a synchronous belt to rotate at the same direction and speed; the cantilever beam unit is provided with a cross beam which is positioned above the coupling water tank and is parallel to the rolling shaft; a linear guide rail is arranged on the cross beam along the length direction, a probe lifting seat is movably arranged along the linear guide rail, a probe frame capable of moving up and down is arranged on the probe lifting seat, and a plurality of downward ultrasonic probes are arranged on the probe frame along the direction parallel to the axis of the roller; the speed reducing motor, the probe lifting seat and the ultrasonic probe are all connected with the controller circuit.

Preferably, the sealing sleeves and the bearings are sleeved on the rolling shafts, and the sealing sleeves are connected to the inner walls and the outer walls of the joints of the walls of the coupling water tank and the rolling shafts; the inner wall of the sealing sleeve is provided with a plurality of annular grooves surrounding the rolling shaft, sealing rings are embedded in the grooves, and the sealing rings are sleeved on the rolling shaft in a hooped mode and are tightly pressed in the annular grooves by the rolling shaft; the bearing is characterized in that a bearing sleeve is arranged outside the bearing and connected to the sealing sleeve, a pressing sheet is further sleeved on the rolling shaft, and the pressing sheet is connected to the bearing sleeve.

Furthermore, sealing gaskets are arranged between the sealing sleeve and the wall of the coupling water tank, between the bearing sleeve and the sealing sleeve and between the pressing plate and the bearing sleeve.

Preferably, each roller comprises a connecting section at two ends and a detecting part bearing section at a middle section, the connecting section is connected to the wall of the coupling water tank through a bearing and a sealing sleeve, and the connecting section is coaxially assembled and connected with the detecting part bearing section.

Furthermore, a pair of limiting wheels with adjustable axial positions are respectively sleeved on the bearing section of the detection piece of each rolling shaft, and the opposite surface of each pair of limiting wheels is a vertical plane.

Furthermore, a plurality of friction wheels are respectively sleeved at corresponding positions on the bearing section of the detection piece of each rolling shaft, and the friction wheels are adjustable along the axial position of the rolling shaft.

Preferably, a screw rod parallel to the linear guide rail is arranged on the cross beam, and a sliding block capable of sliding along the linear guide rail and a transmission block matched and connected with the screw rod are arranged on the probe lifting seat; the screw rod is driven by a servo motor arranged on the cross beam to rotate along the axial direction, and the screw rod drives the probe lifting seat to horizontally move along the linear guide rail through the transmission block when rotating; the servo motor is connected with the controller circuit.

Preferably, a cylinder facing downwards vertically is arranged on the probe lifting seat, a C-shaped clamping plate is connected to the lower end of the cylinder, the C-shaped clamping plate is driven by the cylinder to move up and down, and the probe frame is mounted on the C-shaped clamping plate; the air cylinder is connected with the controller circuit.

Furthermore, a cylinder mounting frame with an adjustable vertical position is arranged on the probe lifting seat, and the cylinder is arranged on the cylinder mounting frame.

Furthermore, a pair of clamping blocks is arranged on the probe frame, clamping grooves matched with the C-shaped clamping plates are formed in the opposite positions of the clamping blocks, and the C-shaped clamping plates are inserted into the clamping grooves.

Compared with the prior art, the invention has the beneficial effects that:

(1) the ultrasonic water immersion method is used as a flaw detection mode, the ultrasonic probe does not need to be in direct contact with the shaft to be detected, the abrasion to the probe is effectively reduced, the requirement on the surface smoothness of the shaft to be detected is low, the detection can be carried out before fine machining, the problem can be found as early as possible, the subsequent invalid machining of the failed shaft is avoided, and the production process is improved.

(2) The supporting and rotating mechanism of the shaft to be detected is simple in structure, the driving and transmission parts of the roller are arranged outside the coupling water tank, the influence on the stability of ultrasonic detection signals is reduced, and the problems that the transmission parts are easy to rust and difficult to maintain in liquid are effectively solved.

(3) The multiple probes detect simultaneously, the flaw detection efficiency is effectively improved, the probes and the probe frame are designed into an integrated module, the adaptive probe frame can be selected for quick disassembly and assembly and replacement according to the specification of a shaft piece to be detected and the detection requirement, a better solution is provided especially for the detection of a surface camshaft piece, the whole structure is simple, the operation is convenient, the system linkage is less, and the failure rate of equipment can be effectively reduced.

(4) The automatic detection device has the advantages that the automation degree is high, the working strength of operators is reduced, the misjudgment on detection results is reduced, the automatic detection and identification can be carried out on the internal and surface defects of shaft parts through the probe frame and the operation control software which are arranged in different combination modes, and the industrial production line can be matched through the linkage industrial robot.

Drawings

FIG. 1: the invention is a schematic three-dimensional structure;

FIG. 2: the invention is a schematic view of a top-down structure;

FIG. 3: the invention is a schematic side-view cross-sectional structure;

FIG. 4: the cross section structure of the joint of the wall of the coupling water tank and the roller is shown schematically;

FIG. 5: the invention discloses a disassembly schematic diagram of a bearing and a sealing sleeve;

FIG. 6: the invention discloses a schematic view of an installation structure of a limiting wheel and a friction wheel;

FIG. 7: the invention discloses a partial structure schematic diagram of a probe frame.

In each figure: 1. a detection workbench; 2. a coupling water tank; 3. a cantilever beam unit; 4. a controller;

21. a roller; 22. a bearing; 23. sealing sleeves; 24. a reduction motor; 25. a synchronous belt; 26. a limiting wheel; 27. a friction wheel; 221. a bearing housing; 222. a compression disc; 231. an annular groove; 232. a seal ring;

31. a cross beam; 32. a probe lifting seat; 311. a linear guide rail; 312. a screw rod; 313. a servo motor; 321. a slider; 322. a transmission block; 323. a cylinder; a C-shaped splint; 325. a probe holder; 326. an ultrasonic probe; 327. a cylinder mounting frame; 328. and (7) clamping blocks.

Detailed Description

For a better understanding of the present invention, reference is made to the following detailed description of the preferred embodiments taken in conjunction with the accompanying drawings. The embodiments listed are preferred forms of the invention, not all embodiments, and all other embodiments that can be derived by one of ordinary skill in the art from the embodiments in the present invention without making any creative effort fall within the protection scope of the present invention.

An ultrasonic nondestructive testing device for shaft parts is disclosed, and is shown in fig. 1 to 3, and comprises a detection workbench 1 and a controller 4, wherein a coupling water tank 2 and a cantilever beam unit 3 are arranged on the detection workbench 1, a pair of parallel rolling shafts 21 with the same diameter are arranged in the coupling water tank 2 along the horizontal direction, the rolling shafts 21 are all arranged on the tank wall of the coupling water tank 2 in a penetrating manner, a bearing 22 and a sealing sleeve 23 are arranged at the joint of the rolling shafts 21 and the tank wall, a synchronous belt 25 is connected between the rolling shafts 21 at the position outside the coupling water tank 2, and in a specific embodiment, the synchronous belt 25 is a rubber belt sleeved at the same end part of the two rolling shafts 21; the roller 21 comprises a driving roller and a driven roller, the driving roller is driven by a speed reducing motor 24 arranged on the detection workbench 1 to rotate along the axial direction, and the driven roller is driven to rotate at the same direction and speed by a synchronous belt 25; the cantilever beam unit 3 is provided with a beam 31, the beam 31 is positioned above the coupling water tank 2 and is parallel to the roller 21, a linear guide rail 311 is arranged on the beam 31 along the length direction, a probe lifting seat 32 is movably arranged along the linear guide rail 311, a probe frame 325 capable of moving up and down is arranged on the probe lifting seat 32, and a plurality of downward ultrasonic probes 326 are arranged on the probe frame 325 along the direction parallel to the axis of the roller 21; the speed reduction motor 24, the probe lifting seat 32 and the ultrasonic probe 326 are all connected with the controller 4 through circuits. In practical application, the controller 4 is an industrial personal computer generally used in industry, a multi-channel ultrasonic processing unit, an electrical control unit and a man-machine interaction unit can be built in the controller, the ultrasonic probe 326 and each transmission component are controlled to work through a preset control program according to the specification and the detection requirement of the piece to be detected, and the controller 4 can be arranged on the detection workbench 1 or can be an operation control platform which is additionally and independently arranged. In a specific application, the number and distribution of the ultrasonic probes 326 on the probe holder 325 may be selected and set according to the specification of the shaft to be detected, and the ultrasonic processing unit in the controller 4 may be set according to different detection requirements, such as detecting surface or internal defects. In addition, can also set up the arm separately by detection workstation 1, control through controller 4, accomplish the clamp of waiting to detect the axle piece and get, place and the go-no-go to realize detecting the full-flow automation mechanized operation of detecting a flaw.

When the device is used for carrying out detection and flaw detection operation, coupling media such as water or engine oil and the like are added into a coupling water tank 2, a shaft to be detected is horizontally placed between two rollers 21 and is integrally immersed in the coupling media, and the rollers 21 drive the shaft to be detected to synchronously rotate when rotating; the probe lifting seat 32 moves to one end of the shaft to be detected, the probe frame 325 moves downwards, when the surface of the ultrasonic probe 326 and the surface of the shaft to be detected reach an effective acting distance, flaw detection is started, after the detection is completed, the probe lifting seat 32 moves towards the other end of the shaft to be detected, after a certain distance is moved, the next section of detection is performed, after the detection of the whole section of shaft is completed, the shaft to be detected is replaced, the probe lifting seat 32 returns to the initial end, and the detection of the next shaft is continued. The horizontal movement of the probe elevation base 32 and the vertical movement of the probe holder 325 can be controlled manually by an operator through the controller 4, or automatically by a preset program according to the size, specification, etc. of the shaft. Compared with the prior art, the device has the advantages that firstly, the coupling liquid is used as a conducting medium of ultrasonic waves, the ultrasonic probe does not need to be in direct contact with the shaft to be detected, the abrasion to the probe is effectively reduced, the requirement on the smoothness of the surface of the shaft to be detected is low, the detection can be carried out before finish machining, the problem can be found as early as possible, and the subsequent invalid machining of the failed shaft is avoided; secondly, the supporting and rotating mechanism of the shaft to be detected has simple structure, the driving and transmission parts of the roller 21 are arranged outside the coupling water tank 2, the influence on the stability of the ultrasonic detection signal is reduced, and the problem that the transmission parts are easy to rust in liquid is effectively solved; and thirdly, a plurality of probes detect simultaneously, the flaw detection efficiency is effectively improved, the ultrasonic probe 326 and the probe frame 325 are designed into an integrated module, the probe frame 325 matched with the ultrasonic probe 326 can be selected to be quickly disassembled and replaced according to the specification of a shaft to be detected, the whole structure is simple, the operation is convenient, the system linkage is less, and the failure rate of equipment can be effectively reduced.

In the invention, the roller 21 is used for supporting and rotating the shaft to be detected inside the coupling water tank 2, and the driving and transmission parts of the roller 21 are arranged outside the coupling water tank 2, therefore, the roller 21 is arranged on the wall of the coupling water tank 2 in a penetrating way, and in order to ensure that the roller 21 rotates stably and prevent the coupling liquid in the coupling water tank 2 from leaking out, a bearing 22 and a sealing sleeve 23 are arranged at the joint of the roller 21 and the wall of the coupling water tank 2. In a preferred embodiment, as shown in fig. 4 to 5, the sealing sleeve 23 and the bearing 22 are both sleeved on the roller 21, the sealing sleeve 23 is connected to the inner wall and the outer wall of each joint between the wall of the coupling water tank 2 and the roller 21, the inner cavity wall of the sealing sleeve 23 is provided with a plurality of annular grooves 231 surrounding the roller 21, the annular grooves 231 are embedded with sealing rings 232, and the sealing rings 232 are sleeved on the roller 21 and are compressed in the annular grooves 231 by the roller 21. A bearing sleeve 221 is arranged outside the bearing 22, the bearing sleeve 221 is connected to the sealing sleeve 23, a pressing disc 222 is further sleeved on the rolling shaft 21, and the pressing disc 222 is connected to the bearing sleeve 221. In a specific application, the sealing ring 232 is made of an elastic rubber material, in order to further improve the sealing effect, a circle of spring can be wrapped inside the rubber, so that the sealing ring 232 is tightly sleeved on the roller 21, and through experimental verification, the sealing ring 232 can effectively prevent the coupling liquid from leaking out of the connection position of the roller 21 and the sealing sleeve 23. Since the rotation speed of the roller 21 is slow in actual use, the seal ring 232 does not affect the rotation of the roller 21. In addition, in specific application, the sealing sleeve 23 and the wall of the coupling water tank 2, the bearing sleeve 221 and the sealing sleeve 23, and the pressing plate 222 and the bearing sleeve 223 are fixedly connected through bolts, and a sealing gasket made of rubber can be arranged at the connecting part, so that the overall sealing performance of the connecting part is further improved. In a specific embodiment, the roller 21 is provided with a step-shaped portion with a slightly smaller end diameter at a portion sleeved near the outer end pressing piece 222, when the pressing pieces 222 sleeved at two ends of the roller 21 are connected to the bearing sleeve 221, the pressing pieces 222 sleeved at two ends of the roller 21 are pressed on the step at the same time, and displacement of the roller 21 in the axial direction can be effectively limited by the relative action of the pressing pieces 222 at two ends on the roller 21.

In a preferred embodiment, the roller 21 is formed by three segments, and includes a connecting segment at two ends and a detecting element supporting segment at a middle segment, the connecting segment is connected to the wall of the coupling water tank 2 through a bearing 22 and a sealing sleeve 23, and the connecting segment and the detecting element supporting segment are coaxially assembled and connected. The effect lies in, when detecting the axle piece of different specifications, when needing to change roller 21, only need to change the detection piece bearing section in middle section, need not to carry out the reassembly at

roller

21 and 2 tank wall connection positions of coupling water tank, improved the operating efficiency. In a specific application, as shown in fig. 6, the connecting portions of the connecting section and the detecting member supporting section are mutually matched and clamped, and are fastened through bolts.

During the detection operation, the shaft member to be detected is placed between the two rollers 21 and is driven by the rollers 21 to rotate synchronously, and when the shaft member to be detected rotates, the shaft member to be detected may displace along the axial direction. In a preferred embodiment, referring to fig. 6, a pair of limiting wheels 26 with adjustable axial positions are respectively sleeved at corresponding positions of the detecting element supporting sections of the two rollers 21, and the opposite surface of each pair of limiting wheels 26 is a vertical plane. The limiting wheels 26 are arranged to limit the position of the shaft to be detected between each pair of limiting wheels 26 so as to prevent axial displacement, so that the stability of detection operation is improved, and the axial positions of the limiting wheels 26 along the roller 21 are adjustable so as to meet the limiting requirements of shaft parts with different lengths. In a specific embodiment, the limiting wheel 26 is provided with a collar which is sleeved on the roller 21, the collar is provided with a screw hole, the limiting wheel 26 is positioned by screwing a nut into the screw hole and pressing the nut on the roller 21, and the axial position can be adjusted by loosening the nut to move the limiting wheel 26 during adjustment. In addition, the axial position of the limiting wheel 26 can be adjusted by providing an elastic clamping ring or block on the limiting wheel 26. According to actual operation experience, when the rotation direction of the roller 21 is unchanged, if the shaft on the roller 21 is axially displaced, the shaft can move towards the same direction, the limiting wheel 26 on one side can play a limiting role, therefore, the distance between the two limiting wheels 26 can be adjusted to be longer than the length of the shaft, the shaft does not need to be tightly matched with the length of the shaft, the problem that the shaft is not convenient to put in due to the undersize gap between the two ends of the shaft and the limiting wheel 26 can not occur, and the problem that the rotation of the shaft is influenced due to the fact that the shaft is clamped by the limiting wheels 26 can not occur.

In a preferred embodiment, referring to fig. 6, a plurality of friction wheels 27 are sleeved at corresponding positions of the detecting element bearing sections of the rollers 21, the friction wheels 27 are arranged to increase the friction force between the rollers 21 and the detecting elements, so as to avoid slipping during rotation, and in a specific application, the surfaces of the friction wheels 27 may be made of materials with higher friction coefficients, such as rubber, nylon, and the like. In order to adapt to shaft members with different sizes and specifications, in a preferred embodiment, the position of the friction wheel 27 along the axial direction of the roller 21 is adjustable, and the position adjustment is implemented in the same manner as the adjustment of the limiting wheel 26 described in the previous paragraph.

In the detecting device provided by the present invention, the probe lifting seat 32 moves horizontally along the linear guide 311, and the purpose is to drive the probe holder 325 to move above the shaft to be detected, thereby completing the detection of the whole shaft. In a preferred embodiment, a screw 312 parallel to the linear guide 311 is disposed on the beam 31, a slider 321 sliding along the linear guide 311 and a transmission block 322 cooperatively connected with the screw 312 are disposed on the probe lifting seat 32, the screw 312 is driven by a servo motor 313 disposed on the beam 31 to rotate along the axial direction, when the screw 312 rotates, the transmission block 322 drives the probe lifting seat 32 to horizontally move along the linear guide 311, and the servo motor 313 is electrically connected with the controller 4. The probe lifting seat 32 is driven to move horizontally through the transmission of the screw rod 312, so that the structure is simpler and the control is easy. In addition, the probe lifting seat 32 can be driven by other means such as an electric sliding table, a belt, or a chain transmission, for example, in the horizontal direction.

In the detecting device provided by the present invention, the probe holder 325 capable of moving up and down is arranged on the probe lifting seat 32, and the purpose is to move the ultrasonic probe 326 on the probe holder 325 close to the surface of the shaft to be detected, so as to achieve effective detecting distance. In a preferred embodiment, a cylinder 323 facing downwards vertically is arranged on the probe lifting seat 32, a C-shaped clamp plate 324 is connected to the top end of the piston of the cylinder 323, the C-shaped clamp plate 324 is driven by the cylinder 323 to move up and down, the probe holder 325 is mounted on the C-shaped clamp plate 324, and the cylinder 323 is electrically connected with the controller 4. The probe holder 325 can be easily detached by driving the cylinder 323, which is easier to control and providing the C-shaped clamp plate 324.

In a preferred embodiment, a cylinder mounting block 327 with an adjustable vertical position is disposed on the probe lifting seat 32, and the cylinder 323 is disposed on the cylinder mounting block 327. In a specific embodiment, the vertical position of the cylinder mount 327 can be adjusted by providing an adjusting screw, a rack, or the like. A vertically adjustable cylinder mount 327 is provided to reduce the control requirements for the stroke of the cylinder 323 during the inspection operation. Before detection, the piston of the air cylinder 323 moves downwards to the maximum stroke, the height of the air cylinder mounting frame 327 is adjusted, the distance between the ultrasonic probe 326 and the surface of the shaft piece to be detected meets the detection requirement, when the shaft pieces of the same batch are detected, the piston of the air cylinder 232 moves downwards to the maximum stroke for detection, the distance of each movement of the piston of the air cylinder 232 does not need to be calculated and set, and the control program is simplified.

In a preferred embodiment, referring to fig. 7, a pair of clips 328 are provided on the probe holder 325, and the clips 328 are oppositely positioned with slots matching with the C-shaped clamp plate 324, and the C-shaped clamp plate 324 is inserted into the slots. Through setting up fixture block 328 and draw-in groove, the operation when having further simplified the dismouting probe frame 325, the quick assembly disassembly and the change probe frame 325 of being convenient for. In a specific embodiment, the latch 328 may be fixedly disposed on the probe holder 325, or may be disposed on the probe holder 325 in a relatively movable manner and elastically returning inward.

In conclusion, the ultrasonic detection device for the shaft part provided by the invention effectively solves the problems of complex structure, inconvenience in operation, high requirement on surface smoothness of the part to be detected and the like of the conventional flaw detection device for the shaft part, and has high utilization value and use significance.

While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. The utility model provides an axle type ultrasonic wave nondestructive test device, includes testing table (1) and controller (4), its characterized in that:

the detection workbench (1) is provided with a coupling water tank (2) and a cantilever beam unit (3); a pair of parallel rolling shafts (21) with the same diameter are arranged in the coupling water tank (2) along the horizontal direction, the rolling shafts (21) are all arranged on the tank wall of the coupling water tank (2) in a penetrating mode, and a bearing (22) and a sealing sleeve (23) are arranged at the joint of the rolling shafts (21) and the tank wall; a synchronous belt (25) is connected between the rollers (21) at a position outside the coupling water tank (2); the roller (21) comprises a driving roller and a driven roller, wherein the driving roller is driven by a speed reducing motor (24) arranged on the detection workbench (1) to rotate along the axial direction, and the driven roller is driven by a synchronous belt (25) to rotate at the same direction and speed;

a beam (31) is arranged on the cantilever beam unit (3), and the beam (31) is positioned above the coupling water tank (2) and is parallel to the roller (21); a linear guide rail (311) is arranged on the cross beam (31) along the length direction, a probe lifting seat (32) is movably arranged along the linear guide rail (311), a probe frame (325) capable of moving up and down is arranged on the probe lifting seat (32), and a plurality of downward ultrasonic probes (326) are arranged on the probe frame (325) along the direction parallel to the axis of the roller (21);

the speed reducing motor (24), the probe lifting seat (32) and the ultrasonic probe (326) are all in circuit connection with the controller (4).

2. The ultrasonic nondestructive testing device for shaft parts according to claim 1, characterized in that: the sealing sleeve (23) and the bearing (22) are sleeved on the roller (21), and the sealing sleeve (23) is connected to the inner wall and the outer wall of each connection part of the box wall of the coupling water tank (2) and the roller (21); the inner cavity wall of the sealing sleeve (23) is provided with a plurality of annular grooves (231) surrounding the roller (21), sealing rings (232) are embedded in the annular grooves (231), and the sealing rings (232) are sleeved on the roller (21) and are pressed in the annular grooves (231) by the roller (21); the bearing (22) is externally provided with a bearing sleeve (221), the bearing sleeve (221) is connected to the sealing sleeve (23), the rolling shaft (21) is sleeved with a pressing disc (222), and the pressing disc (222) is connected to the bearing sleeve (221).

3. The ultrasonic nondestructive testing device for shaft parts according to claim 2, characterized in that: sealing gaskets are arranged between the sealing sleeve (23) and the wall of the coupling water tank (2), between the bearing sleeve (221) and the sealing sleeve (23), and between the pressing disc (222) and the bearing sleeve (221).

4. The ultrasonic nondestructive testing device for shaft parts according to claim 1, characterized in that: each roller (21) comprises a connecting section and a detecting part bearing section, the connecting section is located at two ends of the roller, the detecting part bearing section is located in the middle of the roller, the connecting section is connected to the wall of the coupling water tank (2) through a bearing (22) and a sealing sleeve (23), and the connecting section is coaxially assembled and connected with the detecting part bearing section.

5. The ultrasonic nondestructive inspection apparatus for shaft parts according to claim 4, wherein: a pair of limiting wheels (26) with adjustable axial positions are respectively sleeved on the detection piece bearing sections of the rollers (21), and the opposite surfaces of each pair of limiting wheels (26) are vertical planes.

6. The ultrasonic nondestructive testing device for shaft parts as set forth in claim 4, wherein: a plurality of friction wheels (27) are respectively sleeved at corresponding positions on the bearing sections of the detection pieces of the rollers (21), and the friction wheels (27) are adjustable along the axial positions of the rollers (21).

7. The ultrasonic nondestructive testing device for shaft parts according to claim 1, characterized in that: a screw rod (311) parallel to the linear guide rail (32) is arranged on the cross beam (31), and a sliding block (321) capable of sliding along the linear guide rail (311) and a transmission block (322) matched and connected with the screw rod (312) are arranged on the probe lifting seat (32); the screw rod (312) is driven by a servo motor (313) arranged on the cross beam (31) to rotate along the axial direction, and the screw rod (312) drives the probe lifting seat (32) to horizontally move along the linear guide rail (311) through the transmission block (322) when rotating; the servo motor (313) is in circuit connection with the controller (4).

8. The ultrasonic nondestructive testing device for shaft parts according to claim 1, characterized in that: a vertically downward cylinder (323) is arranged on the probe lifting seat (32), the top end of a piston of the cylinder (323) is connected with a C-shaped clamp plate (333), the C-shaped clamp plate (324) is driven by the cylinder (323) to move up and down, and the probe frame (325) is mounted on the C-shaped clamp plate (324); the air cylinder (323) is in circuit connection with the controller (4).

9. The ultrasonic nondestructive testing device for shaft parts according to claim 8, wherein: the lifting seat (32) is provided with a cylinder mounting frame (327) with an adjustable vertical position, and the cylinder (323) is arranged on the cylinder mounting frame (327).

10. The ultrasonic nondestructive testing device for shaft parts according to claim 8, wherein: a pair of clamping blocks (328) is arranged on the probe frame (325), clamping grooves matched with the C-shaped clamping plates (324) are formed in the opposite positions of the clamping blocks (328), and the C-shaped clamping plates (324) are inserted into the clamping grooves.