阅读说明：本技术 一种厚壁管材纵向缺陷的检测方法 (Method for detecting longitudinal defects of thick-wall pipe ) 是由 鞠双 李富成 年祥祥 陈利伟 于 2021-06-24 设计创作，主要内容包括：本申请涉及一种厚壁管材纵向缺陷的检测方法,在脉冲反射法的基础上对钢管进行自动检测,采用回波高度法对缺陷进行定位,同时测定其尺寸和埋藏深度。本发明能够评定缺陷的大小和埋藏深度,解决了钢管纵向缺陷定量、定位等超声检测技术难题,可清晰的定位裂缝缺陷在管材上的位置。(The application relates to a method for detecting longitudinal defects of thick-wall pipes, which is used for automatically detecting a steel pipe on the basis of a pulse reflection method, positioning the defects by adopting an echo height method and simultaneously measuring the size and the burial depth of the steel pipe. The method can evaluate the size and the burial depth of the defect, solves the technical problems of ultrasonic detection such as quantification and positioning of longitudinal defects of the steel pipe and the like, and can clearly position the position of the crack defect on the pipe.)

1. A method for detecting longitudinal defects of thick-wall pipes is characterized by comprising the following steps: comprises the following steps

S1, driving the pipe (1) to rotate relative to the detector and move axially along the rotating edge through a pipe driving device;

s2, flaw detection is carried out on the pipe (1) by adopting ultrasonic detection equipment and utilizing a pulse reflection method;

s3, adjusting the scanning speed and the detection sensitivity of the instrument to enable the time-base line scale to be in proportion to the sound propagation distance in the material, and determining the depth of the defect (32);

s4, determining the position of the defect (32) through outer circle circumferential detection and inner wall circumferential detection;

s5, the height of the echo of the defect (32) is expressed by the decibel number of attenuation or gain required by the echo peak value to fall or rise to the reference height, and the size of the defect (32) is determined.

2. The method for detecting the longitudinal defect of the thick-wall pipe according to claim 1, wherein the method comprises the following steps: for step S3, when the thickness x of the detected part is ≧ 3N, a low-wave adjustment method can be used, and for the hollow cylinder, the decibel difference between the cylindrical curved bottom surface and the flat-bottom hollow echo at the same distance isIn the formula, d is the inner diameter of the hollow cylinder; d is the outer diameter of the cylinder; when the probe is aligned to the lower surface of the intact zone, the gain is adjusted to enable the low wave B1 to reach the reference height, and then the gain delta dB is obtained by using an attenuator; if x is less than or equal to 3N, a test block adjusting method can be used, the sensitivity of the test block can be adjusted by selecting the test block with an artificial reflector, such as CS I and CS II, the probe is aligned to the flat low hole of the test block during adjustment, and the gain is adjusted to enable the echo of the flat low hole to reach the reference height.

3. The method for detecting the longitudinal defect of the thick-wall pipe according to claim 1, wherein the method comprises the following steps: and S2, selecting a longitudinal wave oblique probe, and obliquely inputting the longitudinal wave to the surface of the detected pipe (1), wherein the input angle is between a first critical angle and a second critical angle.

4. The method for detecting the longitudinal defect of the thick-wall pipe according to claim 1, wherein the method comprises the following steps: tubular product (1) drive arrangement includes along guide rail (2), the sliding connection base (3) on guide rail (2) that tubular product (1) axial set up, installs main support (4) on base (3), rotate first runner (10) of connecting on main support (4), be used for driving base (3) along the gliding first drive assembly (5) of guide rail (2) length direction, main support (4) are equipped with two at least along guide rail (2) length direction, be equipped with on main support (4) and be used for supplying tubular product (1) to inlay half slot (8) of establishing, half slot (8) intercommunication main support (4) up end, first runner (10) are located half slot (8) cell wall and rotate and connect in main support (4), and first runner (10) are equipped with two at least and are located half slot (8) cell wall both sides respectively, install on base (3) and be used for ordering about first runner (10) pivoted second drive assembly (9).

5. The method for detecting the longitudinal defect of the thick-wall pipe according to claim 4, wherein the method comprises the following steps: the upper end face of the main support (4) comprises two top end faces located on two sides of the semicircular groove (8), an auxiliary support (11) is arranged on the top end face, the auxiliary support (11) and the main support (4) are spliced to form an optimal arc groove (12), and a second rotating wheel (13) is rotatably connected to the inner wall of the auxiliary support (11).

6. The method for detecting the longitudinal defect of the thick-wall pipe according to claim 5, wherein the method comprises the following steps: the auxiliary support (11) is rotatably connected to the main support (4) through a rotating piece (14), and the rotating piece (14) is used for enabling the auxiliary support (11) to rotate relative to the main support (4) to be away from the top end face.

7. The method for detecting the longitudinal defect of the thick-wall pipe according to claim 6, wherein the method comprises the following steps: a linkage assembly (18) is arranged between the auxiliary support (11) and the guide rail (2), and the linkage assembly (18) is used for driving the auxiliary support (11) moving to the ultrasonic detection equipment to rotate away from the main support (4).

8. The method for detecting the longitudinal defect of the thick-wall pipe according to claim 7, wherein the method comprises the following steps: the rotating part (14) comprises a first connecting seat (15) fixedly installed on the main support (4), a second connecting seat (16) fixedly installed on the auxiliary support (11), a rotating shaft (17) fixedly connected to the second connecting seat (16) and rotatably connected to the first connecting seat (15), the linkage assembly (18) comprises a force transmission gear (19) rotatably connected to the main support (4), a transmission rail (20) fixedly installed on the guide rail (2) along the length direction, a first rack (21), a transmission assembly (22) and a reset piece, a through groove (24) is formed in the transmission rail (20) along the length direction of the guide rail (2), the through groove (24) is used for enabling the force transmission gear (19) to enter the through groove (24) along with the movement of the base (3) relative to the guide rail (2), the first rack (21) is fixedly installed in the through groove (24) along the length direction of the guide rail (2), when the force transmission gear (19) enters the through groove (24), the force transmission gear (19) is meshed with the first rack (21), and the transmission assembly (22) is used for transmitting the rotating force of the force transmission gear (19) to the rotating shaft (17); the reset piece is used for enabling the auxiliary support (11) to be restored to a state of being abutted to the top end face of the main support (4) after the force transmission gear (19) is separated from the through groove (24).

9. The method for detecting the longitudinal defect of the thick-wall pipe according to claim 8, wherein the method comprises the following steps: the reset piece comprises a second rack (23), the first rack (21) and the second rack (23) are respectively located on the upper end wall and the lower end wall of the through groove (24), the first rack (21) and the second rack (23) respectively comprise a polished rod part (26) and a toothed part (25), the toothed part (25) of the first rack (21) corresponds to the polished rod part (26) of the second rack (23), and the polished rod part (26) of the first rack (21) corresponds to the toothed part (25) of the second rack (23).

10. The method for detecting the longitudinal defect of the thick-wall pipe according to claim 8, wherein the method comprises the following steps: the transmission assembly (22) comprises a transmission shaft (27) rotatably connected to the upper end of the main support (4), a belt transmission mechanism (28), a first bevel gear (29) fixedly sleeved on the transmission shaft (27) and a second bevel gear (30) fixedly sleeved on the rotation shaft (17), the second bevel gear (30) is meshed with the first bevel gear (29), and the belt transmission mechanism (28) is used for transmitting a rotating pair of the force transmission gear (19) to the transmission shaft (27).

Technical Field

The application relates to the field of steel pipe detection, in particular to a method for detecting longitudinal defects of a thick-wall pipe.

Background

Because the thick wall steel pipe is safe and reliable, has the irreplaceable advantage of other tubular products, widely uses in petrochemical industry, electric power industry etc..

The thick-walled steel pipe is obtained by a piercing method in which piercing is performed by a piercing mill, rolling is performed by a roll, and finally, sizing, rolling, and flattening are performed by a mandrel mill. Cracks may occur inside the thick-walled seamless steel pipe during the manufacturing process.

But the method is limited by the fact that no effective method for detecting the internal defects of the thick-wall pipe exists at present, quantitative evaluation on the defects of the thick-wall pipe is difficult, and potential safety hazards are buried for subsequent use.

In view of the above-mentioned related technologies, the inventors consider that the existing detection method has a defect that the crack detection cannot be performed on the thick-wall pipe.

Disclosure of Invention

In order to detect the crack defect of the pipe,

the application provides a method for detecting longitudinal defects of thick-wall pipes, which adopts the following technical scheme:

a method for detecting longitudinal defects of a thick-wall pipe comprises the following steps

S1, driving the pipe to axially move along the rotating edge of the detector relative to the pipe driving device;

s2, flaw detection is carried out on the pipe by adopting an ultrasonic detection device and utilizing a pulse reflection method;

s3, adjusting the scanning speed and detection sensitivity of the instrument to make the time-base line scale and the distance of sound transmission in the material be in a certain proportion, thereby determining the depth of the defect;

s4, determining the position of the defect through outer circle circumferential detection and inner wall circumferential detection;

and S5, representing the height of the defect echo by using the decibel number of attenuation or gain required by the echo peak value to fall or rise to the reference height, and determining the size of the defect.

By adopting the technical scheme, the pipe is automatically detected on the basis of a pulse reflection method, the defects are positioned by adopting an echo height method, and the size and the burial depth of the pipe are measured simultaneously. The method can evaluate the size and the burial depth of the defect, so that the position of the defect of the pipe can be clearer.

Optionally, for step S3, when the thickness x of the probed part is ≧ 3N, a low-wave adjustment method may be adopted, and for the hollow cylinder, the decibel difference between the cylindrical curved bottom surface and the flat-bottom hollow echo at the same distance isIn the formula, d is the inner diameter of the hollow cylinder; d is the outer diameter of the cylinder; when the probe is aligned with the lower surface of the intact zone, the adjustment is carried outThe gain is used for enabling the low wave B1 to reach the reference height, and then the gain delta dB is obtained by an attenuator; if x is less than or equal to 3N, a test block adjusting method can be used, the sensitivity of the test block can be adjusted by selecting the test block with an artificial reflector, such as CS I and CS II, the probe is aligned to the flat low hole of the test block during adjustment, and the gain is adjusted to enable the echo of the flat low hole to reach the reference height.

By adopting the technical scheme, the depth of the defect is determined.

Optionally, for step S2, a longitudinal wave oblique probe is selected, and the longitudinal wave is obliquely incident on the surface of the pipe to be detected, where the incident angle is between the first critical angle and the second critical angle.

By adopting the technical scheme, the ultrasonic detection equipment is more accurate in detection.

Optionally, tubular product drive arrangement includes along guide rail, the base of sliding connection on the guide rail that the tubular product axial set up, installs main support on the base, rotate the first runner of connection on the main support, be used for driving the base along the gliding first drive assembly of guide rail length direction, the main support is equipped with two at least along guide rail length direction, be equipped with on the main support and be used for supplying tubular product to inlay the half slot of establishing, half slot intercommunication main support up end, first runner is located the half slot cell wall and rotates and connect in the main support, and first runner is equipped with two at least and is located half slot cell wall both sides respectively, install on the base and be used for ordering about first runner pivoted second drive assembly.

Through adopting above-mentioned technical scheme, through the slip of the relative guide rail of base, and the rotation of the relative main support of tubular product, realize the limit of tubular product when detecting and rotate along axial displacement. Therefore, the pipe can be subjected to flaw detection stably.

Optionally, the upper end face of the main support comprises two top end faces located at two sides of the semicircular groove, an auxiliary support is arranged on the top end face, the auxiliary support and the main support are spliced to form a major arc groove, and a second rotating wheel is rotatably connected to the inner wall of the auxiliary support.

Through adopting above-mentioned technical scheme, the second wheel has a decurrent spacing power to tubular product, makes tubular product remain stable in the testing process. The detection error caused by the shaking of the pipe is reduced.

Optionally, the secondary support is rotatably connected to the primary support through a rotating member, and the rotating member is used for enabling the secondary support to rotate relative to the primary support to be away from the top end face.

Through adopting above-mentioned technical scheme, when waiting to detect tubular product in the installation, can turn over the auxiliary stand, make tubular product can directly enter into the semicircular groove from the semicircular groove upper end opening through the hoist and mount. Then the auxiliary bracket is rotated to enable the second rotating wheel on the auxiliary bracket to be abutted against the pipe, so that the pipe is convenient to mount.

Optionally, a linkage assembly is arranged between the secondary support and the guide rail, and the linkage assembly is used for driving the secondary support moving to the ultrasonic detection device to rotate away from the primary support.

By adopting the technical scheme, the probability that the auxiliary support influences the detection of the ultrasonic detection equipment is reduced.

Optionally, the rotating member includes a first connecting seat fixedly mounted on the main support, a second connecting seat fixedly mounted on the auxiliary support, and a rotating shaft fixedly connected to the second connecting seat and rotatably connected to the first connecting seat, the linkage assembly includes a force transmission gear rotatably connected to the main support, a transmission rail fixedly mounted on the guide rail along the length direction, a first rack, a transmission assembly, and a reset member, a through groove is formed in the transmission rail along the length direction of the guide rail, the through groove allows the force transmission gear to enter the through groove along with the movement of the base relative to the guide rail, the first rack is fixedly mounted in the through groove along the length direction of the guide rail, when the force transmission gear enters the through groove, the force transmission gear is engaged with the first rack, and the transmission assembly is configured to transmit the rotating force of the force transmission gear to the rotating shaft; the reset piece is used for enabling the force transmission gear to be in a state of abutting against the top end face of the main support after the force transmission gear leaves the through groove.

By adopting the technical scheme, when the base slides on the guide rail, the force transmission gear which moves to the main support corresponding to the auxiliary support below the ultrasonic detection equipment enters the through groove, the force transmission gear rotates under the action of the first rack, and the force transmission gear drives the rotating shaft to rotate under the driving of the force transmission assembly. Therefore, the rotation of the auxiliary support is realized, and the probability that the auxiliary support influences the detection of the ultrasonic detection equipment is reduced. When the auxiliary support moves to leave the ultrasonic detection equipment for detection, the force transmission gear leaves the through groove, the auxiliary support resets under the action of the resetting piece, the pipe is limited, and the pipe is more stable in the detection process.

Optionally, the reset piece includes a second rack, the first rack and the second rack are respectively located at the upper end wall and the lower end wall of the through groove, the first rack and the second rack both include a polished rod portion and a toothed portion, the toothed portion of the first rack corresponds to the polished rod portion of the second rack, and the polished rod portion of the first rack corresponds to the toothed portion of the second rack.

By adopting the technical scheme, when the transmission gear rolls over the toothed part of the first rack, the transmission gear positively rotates to drive the auxiliary support to rotate away from the main support. When the transmission gear rolls through the toothed part of the second rack, the transmission gear reversely rotates to drive the auxiliary support to turn to the main support, and resetting is completed. The whole structure is simple, and the force transmission is stable.

Optionally, the transmission assembly comprises a transmission shaft rotatably connected to the upper end of the main support, a belt transmission mechanism, a first bevel gear fixedly sleeved on the transmission shaft, and a second bevel gear fixedly sleeved on the rotation shaft, wherein the second bevel gear is meshed with the first bevel gear, and the belt transmission mechanism is used for transmitting a rotating pair of the force transmission gear to the transmission shaft.

Through adopting above-mentioned technical scheme, realize the vice transmission of rotation through taking drive mechanism, realize the switching-over of vice rotation through the cooperation of first bevel gear and second bevel gear to the axis of rotation can be along with changeing when making the driving gear rotate, realizes the rotation of the relative main support of auxiliary stand.

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

1. the size and the burying depth of the defects can be evaluated, so that the positions of the defects of the pipe can be clearer;

2. the stability of the pipe in the detection process can be kept, and the detection error is reduced;

3. the influence of the pipe driving device on detection is reduced, and detection errors are reduced.

Drawings

FIG. 1 is a schematic diagram of the outer circumference detection positioning method in the embodiment.

FIG. 2 is a schematic diagram of the inner wall circumferential direction detection positioning method in the embodiment.

FIG. 3 is a schematic diagram of an echo height length measuring method in the embodiment.

FIG. 4 is a schematic structural diagram of the tube driving device in the embodiment.

Fig. 5 is a sectional view of the embodiment.

FIG. 6 is a schematic structural view of a primary stent and a secondary stent in the embodiment.

Fig. 7 is a sectional view at the drive rail in the embodiment.

Description of reference numerals: 1. a pipe; 2. a guide rail; 3. a base; 4. a main support; 5. a first drive assembly; 6. a travel wheel; 7. a drive motor; 8. a semicircular groove; 9. a second drive assembly; 10. a first runner; 11. a sub-mount; 12. a major arc groove; 13. a second runner; 14. a rotating member; 15. a first connecting seat; 16. a second connecting seat; 17. a rotating shaft; 18. a linkage assembly; 19. a force transfer gear; 20. a drive rail; 21. a first rack; 22. a transmission assembly; 23. a second rack; 24. a through groove; 25. a toothed portion; 26. a light bar section; 27. a drive shaft; 28. a belt drive mechanism; 29. a first bevel gear; 30. a second bevel gear; 31. a probe; 32. a defect; 33. and (7) connecting the shafts.

Detailed Description

The present application is described in further detail below with reference to figures 1-7.

The embodiment of the application discloses a method for detecting longitudinal defects of a thick-wall pipe. The method for detecting the longitudinal defects of the thick-wall pipe comprises the following steps

S1, driving the pipe to axially move along the rotating edge of the detector relative to the pipe driving device;

s2, flaw detection is carried out on the pipe by adopting ultrasonic detection equipment and a pulse reflection method, wherein the pipe 1 in the embodiment is a thick-wall seamless steel pipe; specifically, a longitudinal wave oblique probe is selected, longitudinal waves are obliquely incident to the surface of the detected pipe, and the incident angle is between a first critical angle and a second critical angle; the wedge material is provided withMachine glass, the pipe to be detected is steel and can be obtained according to the law of refraction, and the first critical angleI is 27.6 DEG, the second critical angleII is 57.8 degrees.

S3, adjusting the scanning speed and the detection sensitivity of the instrument to enable the time-base line scale to be in proportion to the sound propagation distance in the material, and accordingly determining the depth of the defect 32;

specifically, when the thickness x of the detected part is not less than 3N, a low-wave adjusting method can be adopted, and for the hollow cylinder, i.e. the tube in the embodiment, the decibel difference between the cylindrical curved bottom surface and the flat-bottom hollow echo at the same distance isIn the formula, d is the inner diameter of the hollow cylinder; d is the outer diameter of the cylinder; when the probe is aligned to the lower surface of the intact zone, the gain is adjusted to enable the low wave B1 to reach the reference height, and then the gain delta dB is obtained by using an attenuator; if x is less than or equal to 3N, a test block adjusting method can be used, the sensitivity of the test block can be adjusted by selecting the test block with an artificial reflector, such as CS I and CS II, the probe is aligned to the flat low hole of the test block during adjustment, and the gain is adjusted to enable the echo of the flat low hole to reach the reference height.

S4, determining the position of the defect 32 through outer circle circumferential detection and inner wall circumferential detection;

specifically, the depth H and arc length L of the defect 32 are determined when performing outer circumferential inspection. As shown in fig. 1;

(depth of Defect in Flat workpiece)

(horizontal distance of defect on plane workpiece)

,

Thereby obtaining，

For circumferential inspection of the inner wall, the depth h and arc length l of the defect 32 are determined. As shown in fig. 2;

,

thereby obtaining,

S5, representing the height of the echo of the defect 32 by using the decibel number of attenuation or gain required by the echo peak value to fall or rise to the reference height, and determining the size of the defect 32;

in particular, the length of the defect 32 indicationIs as follows. As shown in fig. 3;

in the formula (I), the compound is shown in the specification,the inner arc length over which the probe 31 moves,= EF, mm; r is the inner radius of the cylinder, namely the inner radius of the pipe, and r = EO, mm;

is the defective sound path, mm.

As shown in fig. 4, the tube driving device includes a guide rail 2, a base 3, a main support 4, and a first driving assembly 5. The guide rails 2 are arranged in two and are arranged along the axial direction of the pipe 1, and the two guide rails 2 are respectively positioned on two sides of the base 3. As shown in fig. 5, the first driving assembly 5 includes a travel wheel 6 rotatably coupled to the base 3 and a driving motor 7 for driving the travel wheel 6 to rotate. The two advancing wheels 6 are arranged and correspond to the two guide rails 2 respectively, and the advancing wheels 6 are embedded in the sliding grooves of the guide rails 2 and are connected to the guide rails 2 in a sliding mode. The base 3 is driven to move along the length direction of the guide rail 2 by the rotation of the travelling wheel 6.

As shown in fig. 5 and 6, the main support 4 is used for supporting the tube 1, and a plurality of main supports 4 are arranged along the length direction of the guide rail 2 and are all fixedly mounted on the base 3. The main support 4 is provided with a semicircular groove 8, and the semicircular groove 8 is used for embedding the pipe 1. The semicircular groove 8 is communicated with the upper end surface of the main bracket 4. Two first rotating wheels 10 are rotatably connected to the main support 4, and the first rotating wheels 10 are located in the semicircular grooves 8 and located on two sides of the semicircular grooves 8 respectively. A second driving assembly 9 for driving the first rotary wheel 10 to rotate is connected to the first rotary wheel. The second driving assembly 9 may be a motor directly connected to the first wheel 10, or a motor mounted on the base 3, and transmits driving force to the first wheel 10 through shaft transmission or other transmission methods, so as to rotate the first wheel 10. Embodied in this embodiment is a motor directly connected to the first wheel 10.

The upper end surface of the main bracket 4 comprises two top end surfaces positioned at two sides of the semicircular groove 8. The top end face is provided with an auxiliary bracket 11, and the auxiliary bracket 11 and the main bracket 4 are spliced to form an optimal arc groove 12. And a second rotating wheel 13 is rotatably connected to the inner wall of the auxiliary bracket 11. The second runner 13 is located in the major arc groove 12.

When in detection, the pipe 1 is placed into the major arc groove 12, the first rotating wheel 10 rotates to drive the pipe 1 to rotate, and the second rotating wheel 13 is used for giving a downward limiting force to the pipe 1, so that the pipe 1 can rotate more stably. The first driving component 5 drives the base 3 to slide on the guide rail 2, so that the tubular product 1 can slide along the axial direction of the tubular product. The two movements are combined, so that the pipe 1 can axially move along the rotating edge, and the detection requirement is met.

As shown in fig. 5 and 6, the sub-bracket 11 is rotatably coupled to the main bracket 4 by a rotating member 14 in order to facilitate the installation of the tube 1. The rotation member 14 includes a first coupling seat 15, a second coupling seat 16, and a rotation shaft 17. The first connecting seat 15 is fixedly installed on the main bracket 4, and the second connecting seat 16 is fixedly installed on the auxiliary bracket 11. The two rotating shafts 17 are respectively fixedly connected to two sides of the second connecting seat 16, and the rotating shafts 17 penetrate through the second connecting seat 16 and are rotatably connected to the first connecting seat 15. Thereby achieving the rotation of the sub-bracket 11 with respect to the main bracket 4.

When it is desired to mount the tube 1 to the main bracket 4, the sub-bracket 11 may be turned away from the top end face of the main bracket 4. So that the pipe 1 can be directly placed into the semicircular groove 8 by hoisting. After the pipe 1 is installed, the auxiliary bracket 11 is rotated until the second rotating wheel 13 abuts against the pipe 1, and the auxiliary bracket 11 abuts against the top end face of the main bracket 4.

As shown in fig. 5 and 6, in order to reduce interference of the sub-mount 11 with the ultrasonic detection apparatus, a linkage assembly 18 is provided between the sub-mount 11 and the guide rail 2. The linkage assembly 18 includes a force transfer gear 19, a drive rail 20, a first rack 21, a drive assembly 22, and a return member. The force transmission gear 19 is rotatably connected to the main stand 4 by a connecting shaft 33. The transmission rail 20 is fixedly installed on the guide rail 2, and the transmission rail 20 is located at a section of the guide rail 2 corresponding to the ultrasonic detection device. A through groove 24 is formed in the transmission rail 20 along the length direction of the guide rail 2, and the through groove 24 is used for enabling the transmission gear 19 to enter the through groove 24 along with the movement of the base 3 relative to the guide rail 2.

As shown in fig. 6 and 7, the restoring member includes a second rack 23. First rack 21 and second rack 23 all set up along guide rail 2 length direction, and first rack 21 and second rack 23 are fixed mounting respectively in logical groove 24 upper and lower both ends end wall. Each of the first and second racks 21 and 23 includes a polished rod portion 26 and a toothed portion 25, the toothed portion 25 of the first rack 21 corresponds to the polished rod portion 26 of the second rack 23, and the polished rod portion 26 of the first rack 21 corresponds to the toothed portion 25 of the second rack 23. The transmission assembly 22 is used to transmit the rotational force of the force transmission gear 19 to the rotational shaft 17.

When the base 3 slides on the guide rail 2, if the transmission gear moves into the through groove 24 of the transmission rail 20, the force transmission gear 19 rotates under the action of the first rack 21 and transmits force to the rotating shaft 17 through the transmission assembly 22, so as to drive the auxiliary bracket 11 to rotate relative to the main bracket 4, and the auxiliary bracket 11 is separated from the top end face of the main bracket 4. At the moment, the upper half part of the pipe 1 is exposed, so that the interference of the auxiliary bracket 11 on the detection of the ultrasonic detection equipment is reduced. Then the base 3 continues to move forward, when the transmission gear rolls over the toothed part 25 of the second rack 23, the transmission gear reversely rotates to drive the auxiliary support 11 to turn to the main support 4, so that the auxiliary support 11 is abutted against the top end surface of the main support 4, the reset is completed, and the limiting on the pipe 1 is recovered.

As shown in fig. 5 and 6, the transmission assembly 22 includes a transmission shaft 27 rotatably connected to the upper end of the main stand 4, a belt transmission mechanism 28, a first bevel gear 29 fixedly secured to the transmission shaft 27, and a second bevel gear 30 fixedly secured to the rotating shaft 17. The second bevel gear 30 is engaged with the first bevel gear 29, and the belt transmission mechanism 28 is used for transmitting the rotation pair of the connecting shaft 33 to the transmission shaft 27. During the rotation of the force transmission gear 19, the belt transmission mechanism 28 transmits the rotating pair of the connecting shaft 33 to the transmission shaft 27, so that the transmission shaft 27 rotates relative to the main bracket 4. When the transmission shaft 27 is rotated by the transmission of the force of the first bevel gear 29 and the second bevel gear 30, the rotating shaft 17 rotates relative to the first connecting seat 15, and the transmission of the rotating force of the transmission gear 19 to the rotating shaft 17 is realized.

The implementation principle of the driving device of the pipe 1 is as follows:

1. installing the pipe 1 to be detected into the semicircular groove 8 of the main bracket 4 by hoisting;

2. rotating the auxiliary support 11 to make the auxiliary support 11 abut against the top end surface of the main support 4, and then abutting the first rotating wheel 10 and the second rotating wheel 13 against the pipe 1;

3. the first rotating wheel 10 rotates to drive the pipe 1 to rotate, the first driving assembly 5 drives the base 3 to slide on the guide rail 2, the pipe 1 is axially moved along the rotating edge, and therefore the detection requirement is met;

4. the transmission gear on the secondary bracket 11 moving to the transmission rail 20 enters the through groove 24, the force transmission gear 19 rotates under the action of the first rack 21 and transmits force to the rotating shaft 17 through the transmission assembly 22, so that the secondary bracket 11 is driven to rotate relative to the main bracket 4, and the secondary bracket 11 is enabled to leave the top end face of the main bracket 4; at the moment, the upper half part of the pipe 1 is exposed, so that the interference of the auxiliary bracket 11 on the detection of the ultrasonic detection equipment is reduced;

5. the auxiliary support 11 continues to move forward along with the base 3, when the transmission gear rolls over the toothed part 25 of the second rack 23, the transmission gear reversely rotates to drive the auxiliary support 11 to turn to the main support 4, so that the auxiliary support 11 is abutted to the top end face of the main support 4, the reset is completed, and the limiting on the pipe 1 is recovered.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.