阅读说明：本技术 一种服役期内的转向架的焊缝裂纹维修方法 (Method for maintaining weld cracks of bogie in service period ) 是由 王彦涛 张泽 朱亮 王志华 赵峰 毛永文 靳庆稳 于 2021-08-23 设计创作，主要内容包括：本发明涉及一种服役期内的转向架的焊缝裂纹维修方法,包括：S1：观察焊缝裂纹位置；S2：对焊缝裂纹位置进行磁粉探伤检测；S3：对探伤出的焊缝裂纹进行打磨；S4：判断焊缝裂纹是否消除,若是,进行到S5,若否,返回S2；S5：打磨裂纹后采用钨极氩弧焊进行焊接；S6：判断焊接后的焊缝位置是否存在焊缝裂纹,若是,打磨清除所焊接的焊缝,并返回S5,若否,进行到S7；S7：判断是否完成了对所有打磨后焊缝的焊接,若是,进行到S8,若否,返回S5；S8：结束。本发明能够提高服役期内转向架焊缝裂纹的维修质量及效率。(The invention relates to a method for maintaining a weld crack of a bogie in a service period, which comprises the following steps: s1: observing the crack position of the welding seam; s2: carrying out magnetic powder flaw detection on the crack position of the welding seam; s3: polishing the flaw detection weld cracks; s4: judging whether the weld cracks are eliminated, if so, going to S5, and if not, returning to S2; s5: after polishing cracks, welding by adopting argon tungsten-arc welding; s6: judging whether a welded seam has a seam crack or not, if so, polishing and removing the welded seam, returning to S5, and if not, going to S7; s7: judging whether welding of all the polished welding seams is finished, if so, going to S8, and if not, returning to S5; s8: and (6) ending. The method can improve the maintenance quality and efficiency of the weld cracks of the bogie in the service period.)

1. A method for maintaining weld cracks of a bogie in service period is characterized by comprising the following steps:

s1: observing the crack position of the welding seam;

s2: carrying out magnetic powder flaw detection on the positions of the weld cracks;

s3: polishing the detected weld cracks, wherein the polishing depth is a preset value d 1;

s4: judging whether the weld cracks are eliminated, if so, going to S5, and if not, returning to S2;

s5: after polishing cracks, welding by argon tungsten-arc welding, wherein the welding thickness is a preset value d 2;

s6: judging whether a welded seam has a seam crack or not, if so, polishing and removing the welded seam, returning to S5, and if not, going to S7;

s7: judging whether welding of all the polished welding seams is finished, if so, going to S8, and if not, returning to S5;

s8: and (6) ending.

2. The in-service bogie weld crack repair method according to claim 1,

the preset value d1 is less than or equal to 2 mm; and/or

The preset value d2 is less than or equal to 2 mm.

3. The in-service bogie weld crack repair method according to claim 1, wherein the step S4 is to determine whether the weld crack is eliminated, and specifically comprises the steps of:

and verifying the polished weld cracks by adopting a magnetic powder inspection detection mode, wherein if the weld cracks are detected, the weld cracks are not cleared, and if the weld cracks are not detected, the weld cracks are cleared.

4. The in-service-period weld crack repair method for the bogie according to claim 1, wherein the step S6 is performed to determine whether a weld crack exists at the welded weld position, and specifically includes:

and verifying the position of the welded weld by adopting a magnetic powder flaw detection mode, wherein if a weld crack is detected, the welded weld position has the weld crack, and if the weld crack is not detected, the welded weld position does not have the weld crack.

5. The in-service bogie weld crack repair method according to any one of claims 1 to 4,

the flaw detection parameters required by the magnetic particle flaw detection at least comprise the pH value of the magnetic suspension, the magnetization direction, the distance between magnet yokes, the holding time of a lifting force test block and the white light intensity.

6. The in-service bogie weld crack repair method according to claim 5,

the magnetic particle inspection mode selects non-fluorescence wet magnetic particle inspection;

the PH value of the magnetic suspension is 7-8; the magnetization direction is cross vertical magnetization; the distance between the magnetic yokes is 80-125 mm; the holding time of the lifting force test block is more than or equal to 3 seconds; the white light intensity is greater than or equal to 600 Lx.

7. The in-service bogie weld crack repair method according to any one of claims 1 to 4,

the welding parameters required by the argon tungsten-arc welding at least comprise current magnitude, arc length, gas flow, current polarity, welding speed and welding gun swing amplitude.

8. The in-service bogie weld crack repair method according to claim 7,

the current is 120-150A; the length of the electric arc is 4 mm-5 mm; the gas flow is 7L/min-10L/min; the current polarity is DC/EN; the welding speed is 1.5 mm/s-2 mm/s; the swing amplitude of the welding gun is 4 mm-8 mm.

Technical Field

The invention belongs to the technical field of railway vehicles, and particularly relates to a method for maintaining a weld crack of a bogie in a service period.

Background

The bogie is an important component of a railway vehicle, the structural strength of the bogie is very important, the bogie is generally large in size, the bogie is formed by welding various parts, and the welded seam flaw detection is a key basis for detecting whether the bogie frame is qualified or not. When the appearance of weld cracks is observed on the surface of the bogie, the bogie needs to be maintained in time so as to ensure the structural strength of the bogie.

The existing maintenance mode of the weld cracks of the bogie is to disassemble the bogie from a vehicle body, transport the bogie to a maintenance place and carry out the maintenance by adopting an internal nondestructive inspection mode, the maintenance mode has high operation difficulty and is inflexible, and the internal nondestructive inspection mode has certain requirements on the field environment and the product structure, so that the maintenance of the weld cracks of the bogie has limitation.

Disclosure of Invention

The invention provides a method for maintaining a weld crack of a bogie in a service period, which is used for carrying out flaw detection and polishing on the weld crack of the bogie in the service period layer by layer, accurately finding the position of the crack and improving the maintenance quality by welding layer by layer; the bogie does not need to be disassembled, the operation is convenient and fast, and the maintenance efficiency is high.

In order to achieve the technical purpose, the invention provides the following technical scheme:

the application provides a method for maintaining weld cracks of a bogie in a service period, which is characterized by comprising the following steps:

s1: observing the crack position of the welding seam;

s2: carrying out magnetic powder flaw detection on the positions of the weld cracks;

s3: polishing the detected weld cracks, wherein the polishing depth is a preset value d 1;

s4: judging whether the weld cracks are eliminated, if so, going to S5, and if not, returning to S2;

s5: after polishing cracks, welding by argon tungsten-arc welding, wherein the welding thickness is a preset value d 2;

s6: judging whether a welded seam has a seam crack or not, if so, polishing and removing the welded seam, returning to S5, and if not, going to S7;

s7: judging whether welding of all the polished welding seams is finished, if so, going to S8, and if not, returning to S5;

s8: and (6) ending.

In the application, the preset value d1 is less than or equal to 2 mm; and/or

The preset value d2 is less than or equal to 2 mm.

In this application, the step S4 of determining whether the weld crack is eliminated specifically includes:

and verifying the polished weld cracks by adopting a magnetic powder inspection detection mode, wherein if the weld cracks are detected, the weld cracks are not cleared, and if the weld cracks are not detected, the weld cracks are cleared.

In this application, the step S6 of determining whether there is a weld crack in the welded weld position specifically includes:

and verifying the position of the welded weld by adopting a magnetic powder flaw detection mode, wherein if a weld crack is detected, the welded weld position has the weld crack, and if the weld crack is not detected, the welded weld position does not have the weld crack.

In the application, the flaw detection parameters required by the magnetic particle flaw detection at least comprise the pH value of the magnetic suspension, the magnetization direction, the distance between the magnetic yokes, the holding time of the lifting force test block and the white light intensity.

In the application, the magnetic particle inspection mode selects non-fluorescence wet magnetic particle inspection;

the PH value of the magnetic suspension is 7-8; the magnetization direction is cross vertical magnetization; the distance between the magnetic yokes is 80-125 mm; the holding time of the lifting force test block is more than or equal to 3 seconds; the white light intensity is greater than or equal to 600 Lx.

In the present application, the welding parameters required for the argon tungsten-arc welding at least include current magnitude, arc length, gas flow, current polarity, welding speed and welding gun swing amplitude.

In the application, the current is 120-150A; the length of the electric arc is 4 mm-5 mm; the gas flow is 7L/min-10L/min; the current polarity is DC/EN; the welding speed is 1.5 mm/s-2 mm/s; the swing amplitude of the welding gun is 4 mm-8 mm.

Compared with the prior art, the method for maintaining the weld cracks of the bogie in the service period has the following advantages and beneficial effects:

(1) flaw detection of weld cracks: combining layer-by-layer magnetic powder inspection detection and layer-by-layer polishing, polishing the part with cracks detected by magnetic powder inspection, continuing to perform surface and near-surface crack inspection on the polished part, polishing, performing flaw detection and polishing again, and performing magnetic powder inspection detection and polishing layer-by-layer alternately, so that cracks on the surface of a welding seam, cracks on the surface of the near-welding seam and the trend of the cracks can be accurately judged, and the cracks of the welding seam can be accurately removed;

(2) after the cracks of the welding seams are completely removed, welding the welding seams layer by layer through argon tungsten-arc welding and adding magnetic powder flaw detection, polishing, removing and welding unqualified welding seams again, ensuring the welding quality of each layer of welding seams and improving the maintenance quality of the welding seams;

(3) the maintenance method has low requirements on the field environment and the product structure, can be used for field maintenance of the weld cracks of the bogie in the service period, is convenient to operate, saves time and improves the maintenance efficiency; the well-maintained bogie can be directly put into use, and the idle time of the bogie is reduced.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments of the present invention or the prior art will be briefly described below, and it is obvious that the drawings described below are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a flowchart illustrating a method for repairing a weld crack in a truck in service according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In order to repair weld cracks of a bogie in service, the application provides a maintenance method for weld cracks, wherein the weld cracks comprise weld surface cracks and cracks close to the weld surface.

In appearance, a probe can only determine the position, size (e.g., the length of the weld crack) and direction of the weld crack on the surface by naked eyes, and cannot determine the weld crack near the weld surface.

The application aims to provide a method for accurately and thoroughly judging and repairing weld cracks.

Referring to FIG. 1, a flow diagram of a method of weld crack repair for an in-service truck is shown.

S1: and observing the position of the weld crack.

As described above, the weld crack position in this step can be visually observed by the probe.

S2: and carrying out magnetic powder flaw detection on the crack position of the welding seam.

Magnetic particle inspection is a nondestructive inspection method for inspecting defects on the surface or near surface of ferromagnetic material by accumulating magnetic particles in leakage magnetic field near the defects.

After the ferromagnetic material workpiece is magnetized, due to the discontinuous existence, magnetic lines of force on the surface and the near surface of the workpiece are subjected to local distortion to generate a leakage magnetic field, magnetic powder applied to the surface of the workpiece is adsorbed, and visible magnetic marks are formed under proper illumination, so that the discontinuous position, size, shape and severity are displayed.

The flaw detection method is characterized in that: simple and direct display.

In the present application, the bogie may be a carbon steel bogie.

In this application, the required flaw detection parameters of magnetic particle inspection detection can include magnetic suspension pH value, magnetization direction, yoke interval, lifting power test block retention time and white light intensity.

The magnetic particle inspection mode selects non-fluorescence wet magnetic particle inspection.

The selection of inspection parameters can be seen in the table below.

S3: and grinding the detected weld cracks, wherein the grinding depth is a preset value d 1.

The preset value d1 can be set by the user.

For example, the grinding may be performed using an angle grinder or a shutter wheel.

Since the magnetic particle inspection is mainly used for detecting surface opening discontinuities (especially cracks) and also near-surface discontinuities, the depth of each layer of grinding is d1 in order to obtain accurate crack propagation information.

In addition, a large number of process tests show that the d1 is within 2mm, and the weld cracks can be accurately polished and removed.

S4: and judging whether the weld cracks are removed or not, if so, proceeding to S5, otherwise, returning to S2.

After one layer of grinding, i.e. after the grinding depth d1, the presence of weld cracks is again checked by means of magnetic particle inspection.

If there is no weld crack, it indicates that the weld crack has been removed, and thereafter proceeds to S5.

If the weld cracks still exist, the current weld cracks are not removed after being polished for one time, then the operation is returned to S2, the positions and the trends of the weld cracks are determined again continuously in a magnetic powder inspection mode, the inspected weld cracks are polished again, and the operation is alternated until the weld cracks do not exist after inspection.

Namely, after each polishing, a magnetic powder inspection detection mode is added for verification until the weld cracks are removed.

The alternating operation of mutual matching of the layer-by-layer flaw detection and the layer-by-layer polishing can discover and remove weld cracks on the surface and the near surface, and meanwhile, if the crack at the root of the weld expands to the near weld surface, the crack can also be discovered and removed, so that the position of the weld crack can be accurately judged, and the complete removal of the weld crack can be ensured.

S5: and (5) after polishing the cracks, welding by argon tungsten-arc welding, wherein the welding thickness is a preset value d 2.

The preset value d2 can be set by the user.

And after the weld cracks are polished and removed, performing first-layer welding, wherein the welding thickness is d 2.

The welding characteristics of the argon tungsten-arc welding are that the electric arc energy is concentrated, and the welding wire is filled after the base metal is melted. Therefore, the fusion of the base metal in the welding process can be ensured, and the weld penetration can reach more than 2mm and the fusion is good.

Meanwhile, the welding is open arc welding, so that defects in a weld pool are easy to find, and the welding defects are easy to reduce.

Therefore, the welding thickness d2 of each layer is guaranteed to be within 2mm in the application, so that the welding quality of each welding seam is guaranteed.

In the present application, the welding parameters required for the argon tungsten-arc welding may include current, arc length, gas flow, current polarity, welding speed, and welding gun swing amplitude.

This selection of welding parameters can be seen in the following table.

S6: and judging whether the welded seam has a seam crack or not, if so, polishing and removing the welded seam, returning to S5, and if not, executing to S7.

After the first layer of welding, namely the welding thickness d2, the welded seam is verified to have weld cracks by means of magnetic powder inspection.

If no seam crack is detected, the welded position after welding has no seam crack, which shows that the quality of the welded seam after current welding is good, and the welding of the next layer can be continued.

If the weld cracks are detected, the weld cracks exist at the welding position after welding, which indicates that the quality of the weld joints after welding is unqualified, the welded weld joints with the weld cracks need to be polished and removed, and the process returns to S5.

And returning to S5, namely welding the position of the welded seam after the crack is ground again by adopting argon tungsten-arc welding, and then, proceeding to S6 to judge whether the welded seam position has the weld crack.

Whether the weld crack exists at the weld position is judged by verifying the weld crack in a magnetic particle inspection mode, as described above, and is not described herein any further.

S7: and judging whether welding of all the polished welding seams is finished, if so, going to S8, and if not, returning to S5.

As described above, if no weld crack is detected in the welded weld, it indicates that no weld crack is present in the welded position, which indicates that the quality of the weld after the current welding is good, and the welding of the next layer can be continued, that is, S5.

The welded joint after re-welding still needs to be verified for the presence of weld cracks, the verification process of which is described above in S6.

Whether the welding seam has a welding seam crack after welding needs to be verified after every time, and the welding thickness is guaranteed within 2mm every time, so that the welding quality of each layer of welding seam is guaranteed.

The welding process is repeatedly executed until all the ground welding seams are welded.

Namely, a magnetic powder inspection detection mode is added after each welding to verify the welded welding seam until all the polished welding seams are welded, so that the welded complete welding seam is ensured to have no welding seam cracks.

The alternate operation of layer-by-layer welding and layer-by-layer flaw detection is matched with the polishing operation, so that cracks can not appear at a new welding position, and the maintenance quality of the cracks of the welding seam is ensured.

After magnetic powder inspection and polishing, all polished welding seams are finally formed, and the welding seams can be observed by naked eyes by a detector.

Therefore, whether welding of all the ground welding seams is finished or not can be observed by the detector through naked eyes.

S8: and (6) ending.

And after the welding of all the polished welding seams is finished, the maintenance of the welding seam cracks is finished, and the maintenance operation is finished at the moment.

According to the method for maintaining the weld cracks, the maintenance quality of the weld cracks of the bogie can be ensured through two aspects of crack polishing additional magnetic particle inspection detection and weld welding additional magnetic particle inspection detection; the maintenance method can be used for maintaining the weld cracks of the bogie in the service period, the bogie does not need to be disassembled, the maintenance time is shortened, the operation complexity and difficulty are reduced, the requirements on the operation environment and the product structure are low, the application range is wide, and the learning is high; by using the maintenance method, the maintenance efficiency can be improved, the bogie after being maintained can be directly put into use, and the idle time of the bogie is reduced.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.