阅读说明：本技术 一种打底焊焊枪及打底焊方法 (Backing welding gun and backing welding method ) 是由 于坚 于 2021-09-02 设计创作，主要内容包括：本发明涉及一种打底焊焊枪及打底焊方法,所述焊枪呈η形结构,在焊枪一端设置焊丝,在焊丝下方设置衬垫,焊枪一端也可以设置钨极或激光光纤,所述焊枪的宽度小于焊接坡口根部的组对的间隙,从而能够从该间隙穿过对焊接坡口背面实施打底焊接。将管道的整条焊缝分为长段和短段,将η形焊枪从焊接坡口根部组对间隙穿过对所述长段的焊接坡口背面实施打底焊接,完成所述长段打底焊接后,将η形焊枪从所述短段撤出,从所述短段的焊接坡口正面实施打底焊接,最终完成整条打底焊缝焊接。本发明能够显著提高管道打底焊的焊缝质量及工作效率,减省打磨处理或采购内孔焊接、打磨机器人等成本费用。(The invention relates to a backing welding gun and a backing welding method, wherein the welding gun is of an n-shaped structure, one end of the welding gun is provided with a welding wire, a liner is arranged below the welding wire, one end of the welding gun can also be provided with a tungsten electrode or a laser optical fiber, and the width of the welding gun is smaller than the pairing gap of the root parts of welding grooves, so that backing welding can be carried out on the back surfaces of the welding grooves by penetrating through the gap. Dividing the whole welding seam of the pipeline into a long section and a short section, penetrating an eta-shaped welding gun from the root group of a welding groove to a gap to carry out backing welding on the back of the welding groove of the long section, withdrawing the eta-shaped welding gun from the short section after the long section backing welding is finished, carrying out backing welding from the front of the welding groove of the short section, and finally finishing the whole backing welding seam. The invention can obviously improve the welding seam quality and the working efficiency of the pipeline backing welding, and reduce the cost for polishing treatment or purchasing inner hole welding, polishing robots and the like.)

1. The backing welding gun is characterized in that the welding gun is of an eta-shaped structure, one end of the welding gun is provided with a welding wire (3), and a gasket (5) is arranged below the welding wire (3); the width of the welding gun is smaller than the pairing gap of the root part of the welding groove, so that backing welding can be carried out on the back surface of the welding groove by penetrating through the gap.

2. The backing welding torch according to claim 1 wherein a tungsten electrode or a laser fiber is further provided at one end of said torch.

3. Backing welding gun according to claim 1 or 2, characterized in that the gun is provided with a camera (4).

4. A backing welding method using the welding gun according to any one of claims 1 to 3, characterized by comprising:

dividing the whole welding line of the pipeline into a long section and a short section, wherein the length of the short section is slightly larger than the size of an eta-shaped opening of the welding gun;

penetrating an eta-shaped welding gun from the root group of the welding groove to the gap to carry out backing welding on the back of the welding groove of the long section;

after the long-section backing welding is completed, withdrawing the eta-shaped welding gun from the short section;

and performing backing welding from the front surface of the welding groove of the short section, and finally finishing the whole backing weld seam welding.

5. The backing weld method of claim 4, wherein the weld groove is an I-weld groove or a conventional single-weld groove with a widened gap in the root pair.

6. The back-welding method according to claim 4, wherein the short-length back-welding is performed by grinding both ends of the long length before the short-length back-welding, and then welding and extending from one end of the long length to the other end.

7. The back-welding method of claim 4, characterized in that the short-length back-welding is performed by a conventional method.

8. The backing weld method of claim 4, wherein the liner of the η -torch lines the backing weld puddle during the long-run backing weld.

9. The backing welding method according to claim 4, characterized in that the position, attitude or laser focus of the welding wire, tungsten electrode of the η -type welding torch is observed by a camera during the long-run backing welding.

Technical Field

The invention belongs to the technical field of welding, and particularly relates to a backing welding gun and a backing welding method.

Background

The back appearance of the back welding seam of the backing welding often has the problems of uneven width and formation, uneven height, rough surface, easy generation of depression of the welding seam at the overhead welding position and the like, and has relatively low quality compared with the front welding seam, the back of the back welding seam of the backing welding seam often needs to be polished for welding seams with higher quality requirements, or special inner hole welding and polishing robots are adopted, so that the work efficiency is reduced and the cost is increased; for some important welding structures with inaccessible backs, the poor formation of the backs of some welding seams can easily cause false signal misjudgment of nondestructive testing or stress concentration to become the origin of defects, thus forming potential safety hazards in the operation process of equipment.

Disclosure of Invention

The invention aims to provide a backing welding gun and a backing welding method aiming at the defects in the prior art, and the welding line quality and the working efficiency of the backing welding of pipelines are improved.

The technical scheme of the invention is as follows: a backing welding gun is of an eta-shaped structure, wherein a welding wire is arranged at one end of the welding gun, and a liner is arranged below the welding wire; the width of the welding gun is smaller than the pairing gap of the root part of the welding groove, so that backing welding can be carried out on the back surface of the welding groove by penetrating through the gap.

Further, the backing welding gun as described above may further include a tungsten electrode or a laser fiber at one end of the gun.

Further, the backing welding gun as described above, wherein the welding gun further comprises a camera.

A backing welding method using the welding gun comprises the following steps:

dividing the whole welding line of the pipeline into a long section and a short section, wherein the length of the short section is slightly larger than the size of an eta-shaped opening of the welding gun;

penetrating an eta-shaped welding gun from the root group of the welding groove to the gap to carry out backing welding on the back of the welding groove of the long section;

after the long-section backing welding is completed, withdrawing the eta-shaped welding gun from the short section;

and performing backing welding from the front surface of the welding groove of the short section, and finally finishing the whole backing weld seam welding.

Further, according to the backing welding method, the welding groove is an I-shaped welding groove or a conventional single-side welding groove with an enlarged gap in a root group.

Further, the backing welding method as described above, wherein before the short-segment backing welding is performed, both ends of the long segment are ground and then welded and extended from one end of the long segment to the other end, thereby completing the short-segment backing welding.

Further, the backing welding method as described above, wherein the short-segment backing welding is performed by a conventional method.

Further, the backing welding method as described above, wherein the backing of the η -shaped torch lines the backing weld pool during the long-run backing welding.

Further, the backing welding method as described above, wherein the position, posture or laser focus of the welding wire, tungsten electrode of the η -shaped welding torch is observed by the camera during the long-length backing welding.

The invention has the following beneficial effects: after the backing welding is adopted, compared with the prior art, the welding groove with the expanded gap is formed by the group of root parts by adopting the eta-shaped ultra-narrow flat welding gun, on one hand, most of the common single-side welding and double-side forming backing welding of the root welding bead can be changed into front welding, so that the back welding bead with consistent width, uniform and attractive forming and smooth and controllable residual height is formed, the quality of the welding seam of the backing welding is obviously improved, the working efficiency can be improved, and the cost for polishing treatment or purchasing inner hole welding, polishing robots and the like is saved; on the other hand, the welding groove with the expanded gap by adopting the root group assembly can also reduce the groove assembly difficulty and the groove processing workload, and particularly has obvious benefit compared with the requirement of the conventional narrow gap groove assembly that the truncated edge gap is 0-1 mm. Although a small part of backing welding seams still need to be subjected to conventional single-side welding and double-side forming backing welding, the method has less occupation of the whole backing welding seams and can be specially arranged at a position with a favorable structure, so that the possible adverse effects are further reduced.

Drawings

FIG. 1 is a schematic view of an eta-shaped ultra-narrow flat welding gun used in the present invention;

FIG. 2 is a schematic diagram of dividing a long section and a short section of a backing weld of a pipeline welding groove in the embodiment of the invention;

FIG. 3 is a schematic diagram of a eta-shaped ultra-narrow flat welding gun penetrating through a gap of a welding groove to perform backing welding on the back of the welding groove in the embodiment of the invention;

FIG. 4 is a schematic view of the withdrawing of the eta-shaped ultra-narrow flat welding gun from the short section opening in the embodiment of the invention.

In the figure, 1, 2, 3 tungsten electrodes, 4 welding wires, 5 cameras, 6 liners and 6 pipelines of an eta-shaped ultra-narrow flat welding gun

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

As shown in fig. 1, the invention firstly provides an η -shaped ultra-narrow flat welding gun 1 with a camera 4 and a gasket 5, wherein the width of the welding gun is smaller than the pairing gap of the welding groove root, so that the welding gun can penetrate through the pairing gap of the welding groove root to carry out backing welding on the back of the welding groove. Arranging a tungsten electrode 2 and a welding wire 3 at one end of an eta-shaped ultra-narrow flat welding gun; or the other scheme is that only the welding wire 3 is arranged at one end of the welding gun, and a liner is arranged below the welding wire; or the tungsten electrode 2 is changed into a laser fiber at one end of the welding gun, and a gasket is arranged below the welding wire. When the welding gun is only provided with the welding wire, the welding wire is used as a conductive electrode; when the welding torch is provided with a tungsten electrode, the tungsten electrode serves as a conductive electrode.

The eta-shaped ultra-narrow flat welding gun 1 can be arranged on a mechanical arm of the welding walking trolley, and the position, the posture or the laser focusing of a tungsten electrode and a welding wire of the welding gun can be regulated and controlled by the camera 4 for observation and through the mechanical arm. The liner 5 can be provided with air holes for arrangement and connected with a gas conveying device, and the air blown out through the air holes can play a role in supporting and protecting a bottom welding seam melting pool.

The invention further provides a method for backing welding by adopting the eta-shaped ultra-narrow flat welding gun, which comprises the following steps:

as shown in fig. 2, the whole backing weld of the pipeline 6 is divided into a long section and a short section, the long section is from a point a to a point B in a clockwise direction, and the short section is from a point a to a point B in an anticlockwise direction, wherein the length of the short section is reserved as short as possible, as long as the length of the short section is slightly larger than the size of an eta-shaped opening of the eta-shaped ultra-narrow flat welding gun, so that the eta-shaped ultra-narrow flat welding gun can be ensured to be withdrawn from the short section; the first scheme of the welding groove is an I-shaped welding groove, and the gap of the I-shaped welding groove is 5-15 mm; the second scheme is a conventional single-side welding groove with expanded root group assembly clearance, the root group assembly clearance is 5-15mm, and a smaller root group assembly clearance can be adopted after the size of a welding gun is further reduced.

As shown in fig. 3, penetrating an η -shaped ultra-narrow flat welding gun from the root group of the welding groove to the gap to perform backing welding on the back of the welding groove of the long section; the eta-shaped ultra-narrow flat welding gun 1 can be arranged on a mechanical arm of the welding walking trolley, when backing welding seam welding is carried out, the eta-shaped ultra-narrow flat welding gun 1 penetrates through a gap of 5-15mm from the root group of a welding groove, the position, the posture or the action of a tungsten electrode and a welding wire of the welding gun can be regulated and controlled by the mechanical arm through observation of the camera 4, for example, the tungsten electrode is perpendicular to the welding surface, and swing welding is carried out according to the requirements of a welding process. In addition, the welding can be previewed and moved along the gap of the groove, the track is detected and memorized, and then the welding groove is moved along the direction indicated by the arrow to carry out the front backing welding on the back of the welding groove according to the memory replay. During long-section backing welding, the liner 5 can play a role in backing or protecting gas of a backing weld pool.

After the long section backing weld is completed, withdrawing the eta-shaped welding gun from the short section, as shown in fig. 4; because the reserved length of the short section A-B is slightly larger than the size of the eta-shaped opening of the eta-shaped ultra-narrow flat welding gun 1, the eta-shaped ultra-narrow flat welding gun 1 can move and withdraw along the direction shown by an arrow after the long section bottoming welding is finished.

After the long backing weld seam welding is completed, the surface of the backing weld seam can be detected by using an endoscope, then the short backing weld seam is performed, the two ends of the long section A, B are polished, then the short backing weld seam is completed by using a conventional method to weld and extend from one end A point of the long section to the other end B point of the long section from the front side of the welding groove, and finally the whole backing weld seam welding is completed.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.