CN116275442A - Pipe fitting welding method and compensating ring applied to pipe fitting welding - Google Patents

Abstract

The application discloses a pipe fitting welding method and a compensating ring applied to pipe fitting welding. The pipe fitting welding method comprises the following steps: butt-jointing the base metal pipe fittings to be welded end to end, wherein a compensating ring is arranged on the periphery of the butt joint part of the base metal pipe fittings; and performing vacuum electron beam welding at the butt joint of the base metal pipe fittings, and melting the compensation ring together to form a welding seam at the butt joint of the base metal pipe fittings, wherein the compensation ring is used for enabling the lowest position of the outer surface of the welding seam to be higher than or flush with the outer peripheral surface of the base metal pipe fittings. Through the mode, the risk of the welding line not being full can be reduced, and the welding line is formed by one-time welding, so that the quality of the welding line is guaranteed.

Description

Pipe fitting welding method and compensating ring applied to pipe fitting welding

Technical Field

The application relates to the technical field of welding, in particular to a pipe fitting welding method and a compensating ring applied to pipe fitting welding.

Background

As a welding method with wide application, the vacuum electron beam welding has the characteristics of small linear energy, small welding deformation, pure welding seam and no oxidation, and is suitable for welding materials such as stainless steel, alloy steel and the like. However, when vacuum electron beam welding is applied to welding small pipe fittings with small caliber and large wall thickness, the pipe fittings are small and thick, the heat dissipation in the welding process is slow, the solidification speed of the welding seam is slow, and the compound with lower melting point generated in the welding process is more oozed out from the back surface of the welding seam, so that the problem that the surface of the welding seam is not fully welded easily occurs, and the repairing is usually carried out through argon arc welding, but the quality of the repaired welding seam is difficult to ensure.

Disclosure of Invention

The application provides a pipe fitting welding method and a compensating ring applied to pipe fitting welding, which can reduce the risk of incomplete welding of a welding line, and the welding line is formed by one-step welding, thereby being beneficial to ensuring the quality of the welding line.

The application provides a pipe fitting welding method, which comprises the following steps: butt-jointing the base metal pipe fittings to be welded end to end, wherein a compensating ring is arranged on the periphery of the butt joint part of the base metal pipe fittings; and performing vacuum electron beam welding at the butt joint of the base metal pipe fittings, and melting the compensation ring together to form a welding seam at the butt joint of the base metal pipe fittings, wherein the compensation ring is used for enabling the lowest position of the outer surface of the welding seam to be higher than or flush with the outer peripheral surface of the base metal pipe fittings.

In an embodiment of the present application, the compensation ring includes: a ring body; the clamping part is arranged on the ring main body; the ring main body is used for being annularly arranged on the periphery of the butt joint position of the base metal pipe fitting after the base metal pipe fitting to be welded is subjected to end-to-end butt joint, and the clamping part is used for being clamped at the butt joint position of the base metal pipe fitting; the outer diameter of the ring main body is D1, the inner diameter of the ring main body is D2, and the maximum compensation amount of the welding line is Tmax, wherein D1 is more than or equal to D2+2Tmax.

In an embodiment of the present application, the compensation ring includes: a ring body; the clamping part is arranged on the ring main body; the ring main body is used for being annularly arranged on the periphery of the butt joint position of the base metal pipe fitting after the base metal pipe fitting to be welded is subjected to end-to-end butt joint, and the clamping part is used for being clamped at the butt joint position of the base metal pipe fitting; the inner diameter of the ring main body is D2, and the outer diameter of the parent metal pipe fitting is D3; wherein D2 is more than or equal to D3.

In one embodiment of the present application, the width of the compensating ring is d1, and the width of the weld is d2; wherein d1 is greater than or equal to d2.

In an embodiment of the present application, the compensating ring includes at least two compensating bodies, each of which is sequentially distributed along the circumferential direction of the compensating ring; the step of butt-jointing the base metal pipe fittings to be welded end to end comprises the following steps: sequentially installing the compensation bodies on the periphery of the butt joint part of the base metal pipe fitting; and performing spot welding fixation at the butt joint of the adjacent compensation bodies.

In an embodiment of the present application, before the step of performing vacuum electron beam welding at the butt joint of the base metal pipe pieces, the method includes: controlling the electron beam gun head to uniformly spot-weld the compensation ring along the circumferential direction of the compensation ring; the relative position of the electron beam gun head and the parent metal pipe fitting is calibrated through the spot welding track, so that the electron beam gun head is aligned with the center of the compensation ring; controlling the electron beam gun head to continuously weld the compensation ring along the circumferential direction of the compensation ring; and calibrating the relative positions of the electron beam gun head and the base metal pipe fitting through continuous welding tracks, so that the electron beam gun head is aligned with the center of the compensation ring.

In an embodiment of the present application, the step of performing vacuum electron beam welding at the butt joint of the base pipe members includes: and carrying out vacuum electron beam welding on the butt joint of the base metal pipe fitting by adopting preset welding parameters, wherein the preset welding parameters are matched with the sum of the thickness of the pipe wall of the base metal pipe fitting and the ring thickness of the compensation ring.

In one embodiment of the present application, the step of butt-joining the parent pipe elements to be welded end-to-end includes, prior to: a groove is processed at the end part of the parent metal pipe fitting, so that the grooves of the adjacent parent metal pipe fittings are matched to form a limit groove after the parent metal pipe fittings are in butt joint; the compensation ring comprises a ring main body and a clamping part, wherein the clamping part is convexly arranged on the inner side of the ring main body and is used for being clamped in the limiting groove after the ring main body is annularly arranged on the periphery of the butt joint part of the base metal pipe fitting.

In one embodiment of the present application, the step of butt-joining the parent pipe elements to be welded end-to-end includes: butt-jointing the base metal pipe fittings end to end, and spot-welding and assembling the butt-jointed parts of the base metal pipe fittings; wherein the assembly gap between adjacent parent metal pipe fittings is less than or equal to 0.05mm.

Correspondingly, the application also provides a compensating ring applied to pipe fitting welding. The compensation ring includes: a ring body; the clamping part is arranged on the ring main body; the ring main body is used for being annularly arranged on the periphery of the butt joint position of the base metal pipe fitting after the base metal pipe fitting to be welded is subjected to end-to-end butt joint, and the clamping part is used for being clamped at the butt joint position of the base metal pipe fitting; and the compensation ring is melted together when the vacuum electron beam welding is carried out on the butt joint of the base metal pipe fittings so as to form a welding line at the butt joint of the base metal pipe fittings, wherein the compensation ring is used for enabling the lowest position of the outer surface of the welding line to be higher than or flush with the outer peripheral surface of the base metal pipe fittings.

The beneficial effects of this application are: unlike the prior art, the application provides a pipe welding method and a compensating ring applied to pipe welding. And butt-jointing the base metal pipe fittings to be welded end to end, wherein a compensating ring is arranged on the periphery of the butt joint part of the base metal pipe fittings. And performing vacuum electron beam welding at the butt joint of the base metal pipe fittings, and melting the compensation ring together to form a welding line at the butt joint of the base metal pipe fittings. The lowest part of the outer surface of the welding seam is higher than or flush with the outer peripheral surface of the base metal pipe fitting, namely the compensation ring can effectively solve the problem that the welding seam is not fully welded, so that the risk of the welding seam being not fully welded can be reduced. And the compensation ring is melted together in the welding process, namely the welding line is formed by one-step welding, which is beneficial to ensuring the quality of the welding line.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the description of the embodiments will be briefly introduced below, it being obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic view of a prior art construction of a tube welded by vacuum electron beam welding;

FIG. 2 is a schematic cross-sectional view of an embodiment of a compensation ring on a parent pipe of the present application;

FIG. 3 is a schematic diagram of an embodiment of a compensating ring of the present application;

FIG. 4 is a schematic view of the parent pipe of FIG. 2 with the compensation ring omitted;

FIG. 5 is a schematic view of the structure of the region A of the base pipe fitting shown in FIG. 4;

FIG. 6 is a schematic view showing a sectional structure of the compensating ring B-B shown in FIG. 3;

FIG. 7 is a schematic view of the base pipe fitting of FIG. 2 and the compensating ring C area thereon;

FIG. 8 is a flow chart of an embodiment of a pipe welding method of the present application;

fig. 9 is a schematic flow chart of another embodiment of the pipe welding method of the present application.

Reference numerals illustrate:

10 parent metal pipe fittings; 11 grooves; 12 limit grooves; a 20 compensation ring; 21 a compensation body; a 22-ring body; 23 clamping parts.

Detailed Description

The following description of the embodiments of the present application will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all, of the embodiments of the present application. All other embodiments, based on the embodiments herein, which are within the scope of the protection of the present application, will be within the skill of the art without inventive effort. Furthermore, it should be understood that the detailed description is presented herein for purposes of illustration and explanation only and is not intended to limit the present application. In this application, unless otherwise indicated, terms of orientation such as "upper", "lower", "left" and "right" are generally used to refer to the directions of the drawings in which the device is actually used or in an operating state.

In the present application, unless explicitly specified and limited otherwise, the terms "connected," "stacked," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art as the case may be.

The application provides a pipe fitting welding method and a compensating ring applied to pipe fitting welding, and the pipe fitting welding method and the compensating ring are respectively described in detail below. It should be noted that the following description order of the embodiments is not intended to limit the preferred order of the embodiments of the present application. In the following embodiments, the descriptions of the embodiments are focused on, and for the part that is not described in detail in a certain embodiment, reference may be made to the related descriptions of other embodiments.

As a welding method with wide application, the vacuum electron beam welding has the characteristics of small linear energy, small welding deformation, pure welding seam and no oxidation, and is suitable for welding materials such as stainless steel, alloy steel and the like. The nickel-based alloy (such as NS1402, NS3105, etc.) is commonly used for manufacturing products such as air coolers, ceramic melting furnaces, etc. with complex structures, wherein small pipe fittings such as feeding pipes, measuring pipes, etc. are welded by adopting vacuum electron beam welding (the requirements of design documents). The pipe fitting is of a slender straight pipe and bent pipe structure, has the characteristics of small caliber (phi 10-35 mm), large wall thickness (3-10 mm) and small processing allowance of incoming materials, and is required to be completely welded through a butt welding line of the pipe, qualified in radial detection and high in welding line quality requirement, and can not be welded in a mode of reserving allowance of a groove before welding. Because the nickel-based alloy has higher thermal cracking sensitivity, oxides with larger linear expansion coefficients and the like are easy to generate when the traditional fusion welding is adopted, the risk of generating thermal cracking is increased, and the occurrence of the thermal cracking can be avoided by utilizing vacuum electron beam welding for welding.

However, when small pipe fittings with small welding caliber (phi 10-35 mm) and large wall thickness (3-10 mm) are butted, the pipe fittings are small and thick, the heat dissipation in the welding process is slow, the solidification speed of the welding seam is slow, and the compound with lower melting point generated in the welding process is more oozed from the back of the welding seam, so that the problem of incomplete welding on the surface of the welding seam is easy to occur. Fig. 1 shows that the pipe 31 and the pipe 32 are welded by conventional vacuum electron beam welding, the weld 33 has an insufficient defect, and the depth of the weld 33 at the deepest position of the insufficient defect is T, i.e., the compensation amount of the weld is T.

Repair is often required by argon arc welding, but the quality of the repaired weld is difficult to ensure.

For the problem of incomplete welding of the welding line, a method of embedding a liner can be theoretically adopted to reduce compound exudation on the back surface of the welding line, so that the defect of incomplete welding of the welding line is reduced. However, in practical application, the pipe to be welded is mostly of a structure such as an elongated bent pipe, and the built-in gasket is difficult to take out after welding.

Based on the above problems, the vacuum electron beam welding is carried out on the small pipe fitting by adopting the external compensation ring, so that the problem that the welding line is easy to be unwelded is solved, the risk of unwelded welding line can be reduced, the welding line is formed by one-step welding, the ray detection is qualified, the defects of no thermal crack and the like are overcome, and the quality of the welding line is guaranteed.

Referring to fig. 2, fig. 2 is a schematic cross-sectional view of an embodiment of a parent pipe and a compensating ring thereon.

In one embodiment, a compensating ring 20 is provided for use in pipe welding. The base metal pipe fittings 10 to be welded are butted end to end, and a compensating ring 20 is arranged on the periphery of the butted part of the base metal pipe fittings 10. Vacuum electron beam welding is performed at the butt joint of the base pipe members 10, and the compensation ring 20 is melted together to form a weld at the butt joint of the base pipe members 10. Wherein the compensation ring 20 is used to make the lowest part of the outer surface of the weld joint higher than the outer peripheral surface of the base pipe fitting 10 or flush with the outer peripheral surface of the base pipe fitting 10.

After the welding is completed, the whole weld joint is annular. The lowest point of the outer surface of the weld is understood to be the position of the outer surface of the weld closest to its ring center. The lowest position of the outer surface of the weld being higher than the outer circumferential surface of the parent pipe 10 is understood to mean that the lowest position of the outer surface of the weld is farther from the center line of the parent pipe 10 than the outer circumferential surface of the parent pipe 10, i.e. the weld has a residual height. Whereas when the lowest part of the outer surface of the weld is flush with the outer circumferential surface of the parent pipe 10, it is understood that the residual height of the weld is zero.

By the above mode, the lowest part of the outer surface of the welding seam is higher than the outer peripheral surface of the base metal pipe fitting 10 or is flush with the outer peripheral surface of the base metal pipe fitting 10 by the compensation ring 20, namely the problem that the welding seam is not fully welded can be effectively solved by the compensation ring 20, and therefore the risk of the welding seam being not fully welded can be reduced. And, the compensation ring 20 melts together in the welding process, namely the welding seam is formed by one-step welding, which is beneficial to ensuring the quality of the welding seam. The compensating ring 20 of the embodiment is particularly suitable for the small pipe fitting with small welding caliber (phi 10-35 mm) and large wall thickness (3-10 mm).

Referring to fig. 3, fig. 3 is a schematic structural diagram of an embodiment of the compensating ring of the present application.

In one embodiment, the compensation ring 20 includes a ring body 22 and a clamping portion 23. The engagement portion 23 is provided on the ring main body 22. The ring body 22 is used for being arranged around the outer periphery of the butt joint position of the base metal pipe fitting 10 after the base metal pipe fitting 10 to be welded is butt-jointed end to end, and the clamping part 23 is used for being clamped at the butt joint position of the base metal pipe fitting 10.

Specifically, referring to fig. 4 and 5 together, the end of the base pipe member 10 is provided with a groove 11. After the base metal pipe fittings 10 are butted, the grooves 11 of the adjacent base metal pipe fittings 10 are matched to form limit grooves 12. For example, the bevel 11 at the end of the base pipe 10 is a chamfer with an inclination angle of 45 °, and the width of the bevel 11 in the axial direction of the base pipe 10 is 1mm. After the base metal pipe fittings 10 are butted, V-shaped limit grooves 12 are formed between grooves 11 of adjacent base metal pipe fittings 10 in a matching mode, and the center of each limit groove 12 is the center of a welding line. The cross section of the limiting groove 12 is isosceles right triangle, and the inclined side length is 2mm.

Referring to fig. 6 and 7, the shape of the clamping portion 23 of the compensating ring 20 matches the shape of the limiting groove 12. The cross section of the limiting groove 12 is V-shaped, and the cross section of the clamping part 23 is correspondingly V-shaped. For example, the cross-sectional shape of the engaging portion 23 is also an isosceles right triangle, and the hypotenuse length is also 2mm. After the compensation ring 20 is mounted on the base metal pipe fitting 10, the clamping part 23 is clamped in the limiting groove 12 of the base metal pipe fitting 10, the purposes of limiting and centering the compensation ring 20 are achieved, the position of the compensation ring 20 on the base metal pipe fitting 10 is fixed, the compensation ring 20 is ensured to play a role in compensating a welding seam, and the risk of the welding seam being not full is reduced.

Please continue to refer to fig. 3. In an embodiment, the compensating ring 20 includes at least two compensating bodies 21, and each compensating body 21 is sequentially distributed along the circumferential direction of the compensating ring 20. Specifically, the ring main body 22 and the engaging portion 23 are each divided into at least two parts, and each compensating body 21 is composed of the corresponding ring main body 22 and engaging portion 23.

In this way, the compensating ring 20 of the present embodiment is divided into at least two compensating bodies 21, so that the compensating ring 20 is mounted to the butt joint of the base metal pipe fitting 10, specifically, each compensating body 21 is sequentially mounted on the periphery of the butt joint of the base metal pipe fitting 10, and then the compensating ring 20 is assembled. The design of the compensating ring 20 divided into at least two compensating bodies 21 has wide application range, and can be applied to butt welding of pipe fittings such as straight pipes, bent pipes and the like.

For example, the compensating ring 20 of the present embodiment is divided into two compensating bodies 21, each compensating body 21 has a half-ring structure, and after the two compensating bodies 21 are respectively mounted at the butt joint positions of the base metal pipe fittings 10, the two compensating bodies 21 are assembled into the complete compensating ring 20.

In one embodiment, the outer diameter of the ring body 22 is D1, the inner diameter of the ring body 22 is D2, and the maximum compensation of the weld is Tmax. Wherein D1 is equal to or greater than D2+2Tmax. In this way, it can be ensured that the compensation ring 20 is sufficient to compensate for the weld under-weld defect, further reducing the risk of weld under-weld.

The maximum compensation amount of the weld is understood to be the deepest depth of the weld under-weld defect when the compensation ring 20 is not provided, and is measured according to a large number of welding tests in the early stage.

In one embodiment, the outer diameter of the parent pipe 10 is D3, as shown in fig. 4. Wherein D2 is more than or equal to D3. In this way, the compensation ring 20 can be ensured to be normally sleeved on the outer periphery of the butt joint of the base material pipe fitting 10. The inner diameter D2 of the ring body 22 is equal to the outer diameter D3 of the parent pipe 10, and the inner diameter D2 of the ring body 22 should be left with a positive tolerance of 0mm to 0.1 mm.

In one embodiment, the width of the compensation ring 20 is d1 (as shown in FIG. 5) and the width of the weld is d2. Wherein d1 is greater than or equal to d2. The width d1 of the compensating ring 20 is understood to be the length of the compensating ring 20 in the axial direction of the parent pipe 10, and likewise the width d2 of the weld is understood to be the length of the weld in the axial direction of the parent pipe 10. The width d2 of the weld is measured according to the early welding test, for example, a large number of early welding tests can be selected to measure the average value of the width of the weld. In this way, the compensating ring 20 can cover the welding seam in the axial direction of the base pipe fitting 10, further ensuring that the compensating ring 20 can compensate the welding seam, and reducing the risk of the welding seam not being full.

It should be noted that, the dimensional parameters of the compensating ring 20 in the embodiment of the present application are all measured according to the base pipe fitting 10 and the welding test. In practical application, the device can be flexibly adjusted according to practical requirements, and has good flexibility.

Referring to fig. 8, fig. 8 is a flow chart illustrating an embodiment of a pipe welding method according to the present application. The pipe welding method described in this embodiment is based on the compensating ring described in the above embodiment, and will not be described herein.

S101: and butt-jointing the base metal pipe fittings to be welded end to end, wherein a compensating ring is arranged on the periphery of the butt joint part of the base metal pipe fittings.

In this embodiment, the base material pipe members to be welded are butted end to end, so that the butted base material pipe members are welded and fixed by vacuum electron beam welding. The peripheral ring of butt joint department of parent metal pipe fitting is equipped with the compensation ring, and the compensation ring is used for compensating the welding seam to reduce the risk that the welding seam is not welded fully.

S102: and performing vacuum electron beam welding at the butt joint of the base metal pipe fittings, and melting the compensation ring together to form a welding seam at the butt joint of the base metal pipe fittings, wherein the compensation ring is used for enabling the lowest position of the outer surface of the welding seam to be higher than or flush with the outer peripheral surface of the base metal pipe fittings.

In this embodiment, after the compensation ring is mounted to the butt joint of the base metal pipe members, vacuum electron beam welding is performed at the butt joint of the base metal pipe members, and the compensation ring is melted together to form a weld at the butt joint of the base metal pipe members. The lowest part of the outer surface of the welding seam is higher than or is flush with the outer peripheral surface of the base metal pipe fitting, namely the compensation ring can effectively solve the problem that the welding seam is not fully welded, so that the risk of the welding seam being not fully welded can be reduced. And the compensation ring is melted together in the welding process, namely the welding line is formed by one-step welding, which is beneficial to ensuring the quality of the welding line.

Referring to fig. 9, fig. 9 is a flow chart illustrating another embodiment of the pipe welding method of the present application. The pipe welding method described in this embodiment is based on the compensating ring described in the above embodiment, and will not be described herein.

S201: and cleaning the parent metal pipe fitting.

In this embodiment, the parent metal tube is a nickel-based alloy tube, and the specific brand combinations may be NS1402/NS1402, NS3105/NS3105, NS1402/NS3105, or other similar material brand combinations. And processing grooves at the end parts of the parent metal pipe fittings so as to enable the grooves of the adjacent parent metal pipe fittings to be matched to form limit grooves after the parent metal pipe fittings are in butt joint. The compensation ring comprises a ring main body and a clamping part, wherein the clamping part is convexly arranged on the inner side of the ring main body and is used for being clamped in the limiting groove after the ring main body is annularly arranged on the periphery of the butt joint part of the base metal pipe fitting. In this embodiment, acetone or the like may be used to clean the base material pipe, specifically, acetone or the like is used to wipe and clean the base material pipe and the groove thereon, and then the base material pipe and the groove are dried.

S202: and butt-jointing the base metal pipe fittings to be welded end to end.

In this embodiment, the base pipe members are butted end to end, and spot welding assembly is performed at the butted portions of the base pipe members. Wherein, the assembly clearance between the adjacent parent metal pipe fittings is less than or equal to 0.05mm. Specifically, the base pipe fitting can be assembled by spot welding through argon arc welding, and after the spot welding is finished, the welding spots can be polished to be smooth.

S203: and installing the compensation ring at the butt joint of the base metal pipe fittings.

In this embodiment, after the base material pipe member to be welded is spot-welded, the compensation ring is mounted to the butt joint of the base material pipe member. The compensation ring comprises at least two compensation bodies, each compensation body is sequentially arranged on the periphery of the butt joint position of the base metal pipe fitting in the embodiment, and then spot welding is performed on the butt joint position of the adjacent compensation bodies.

Specifically, the material grade of the compensation ring is kept as consistent as possible with that of the parent pipe fitting. The compensation ring of the embodiment is divided into two compensation bodies, each compensation body is of a semi-ring structure, the inner wall of each compensation body is convexly provided with a clamping part, and the compensation ring structure of the embodiment is easy to process and realize. One of the compensation bodies is embedded into the limit groove from outside to inside along the radial direction of the base metal pipe fitting, and the other compensation body is embedded into the limit groove from outside to inside along the radial direction of the base metal pipe fitting, so that the compensation body installed later and the compensation body installed earlier form a complete compensation ring. The argon arc welding spot welding locking compensation body is adopted, specifically 1 to 2 welding spots are respectively welded at two butt joint positions of the two compensation bodies, and the locking is realized. After the spot welding is completed, the welding spots can be ground to a smooth finish.

S204: and (3) sending the parent metal pipe fitting with the compensation ring into a welding chamber, and vacuumizing the welding chamber.

In this embodiment, after the compensation ring is mounted to the butt joint of the base material pipe members, the base material pipe members to which the compensation ring is mounted are sent into the welding chamber, and the welding chamber is evacuated to perform the subsequent vacuum electron beam welding operation.

S205: and positioning the electron beam gun head.

In this embodiment, the positioning of the electron beam gun head is specifically: the electron beam gun head is controlled to uniformly spot-weld the compensating ring along the circumferential direction of the compensating ring, and the relative position of the electron beam gun head and the base metal pipe fitting is calibrated through a spot welding track, so that the electron beam gun head is aligned with the center of the compensating ring, and the electron beam gun head is positioned and centered; and then, controlling the electron beam gun head to continuously weld the compensating ring along the circumferential direction of the compensating ring, and calibrating the relative position of the electron beam gun head and the base metal pipe fitting through the continuous welding track, so that the electron beam gun head is aligned with the center of the compensating ring, namely, the electron beam gun head walks through the welding track for one time in advance, and the correct centering of the electron beam gun head is ensured.

S206: and performing vacuum electron beam welding at the butt joint of the base metal pipe fittings.

In this embodiment, vacuum electron beam welding is performed at the butt joint of the base material pipe members, and the compensation ring is melted together to form a weld at the butt joint of the base material pipe members. The lowest part of the outer surface of the welding seam is higher than or is flush with the outer peripheral surface of the base metal pipe fitting, namely the compensation ring can effectively solve the problem that the welding seam is not fully welded, so that the risk of the welding seam being not fully welded can be reduced. And the compensation ring is melted together in the welding process, namely the welding line is formed by one-step welding, which is beneficial to ensuring the quality of the welding line.

Specifically, vacuum electron beam welding is performed at the butt joint of the base metal pipe fittings by adopting preset welding parameters. The preset welding parameters are matched with the sum of the thickness of the pipe wall of the base metal pipe and the ring thickness of the compensation ring so as to ensure that the base metal pipe and the compensation ring are thoroughly welded. The preset welding parameters are obtained according to the measurement of the early welding test, for example, the average value of the welding parameters obtained by measuring a large number of early welding tests can be selected. The welding parameters depend on the welding equipment, the brand of the parent metal pipe fitting, the size of the parent metal pipe fitting and other factors. The welding parameters may include, in particular, electron beam current, electron beam gun head voltage, welding speed, focus current, etc.

After the vacuum electron beam welding is completed, whether or not finish welding is performed is selected according to the weld surface forming condition. If the weld is well formed, no finish welding may be performed.

S207: and (5) after the welding is finished, exhausting the welding chamber, and taking out the welded parent metal pipe fitting.

In this embodiment, the welding is completed, the welding chamber is exhausted, and the welded base metal pipe is taken out. The surplus height of the welding seam on the base metal pipe fitting can be polished or processed according to actual requirements.

The technical scheme provided by the embodiment of the application is explained below in combination with a specific application scene.

Example 1:

taking vacuum electron beam welding of a feed pipe head in a ceramic electric melting furnace project as an example, the brand of a parent metal pipe is NS3105/NS3105, the groove specification of the parent metal pipe is phi 26.9mm phi 3.2 mm/phi 26.9mm phi 3.2mm, and the welding process is as follows:

and firstly, wiping and cleaning the bevel of the base metal pipe fitting by using acetone, and drying.

And secondly, assembling the base metal pipe fitting by using argon arc welding, wherein the assembly gap is less than or equal to 0.05mm.

And thirdly, installing the compensation ring to the assembled parent metal pipe fitting. The dimensions of the compensating ring are as follows: the external diameter d1=29.9 mm of the compensation ring, the internal diameter d2=26.9 (0-0.1) mm of the compensation ring, the width d1=5 mm of the compensation ring, the clamping part of the compensation ring is isosceles right triangle with the hypotenuse length of 2mm (matched with a limit groove formed after the base metal pipe fitting is assembled).

Fourth, the parent metal pipe fitting with the compensation ring is sent into a welding chamber, and the welding chamber is vacuumized until the air pressure of the welding chamber is less than or equal to 5 x 10 ^-4 Mpa。

And fifthly, the electron beam gun head is subjected to spot welding positioning, and 3 welding spots are uniformly spot welded so as to position the electron beam gun head. The electron beam current of the electron beam gun head is 10mA, the voltage of the electron beam gun head is 45KV, and the focusing current is 1.70A.

And sixthly, performing vacuum electron beam welding at the butt joint position of the base metal pipe fittings. And carrying out vacuum electron beam welding by adopting preset welding parameters according to the result of the early welding test. The preset welding parameters specifically comprise 45mA of electron beam current, 45KV of electron beam gun head voltage, 65cm/min of welding speed and 1.70A of focusing current.

And seventh, the welding is completed, the welding chamber is exhausted, and the welded parent metal pipe fitting is taken out.

Eighth, the excess weld seam height is ground or machined.

And ninth, performing liquid penetration inspection on the surface of the welding seam, wherein the inspection is qualified according to the standard NB47013.5-15 and the inspection and acceptance is according to the grade 1 welding seam standard.

And tenth, detecting the welding line rays, wherein the inspection is qualified according to the 1-grade welding line standard according to the standard NB 47013.5-15.

Example 1 remarks:

in the third step, the compensating ring dimensions are determined as follows: the inner diameter D2 of the compensating ring is determined according to the outer diameter D3 of the actual parent metal pipe fitting, and the inner diameter d2=d3=26.9 (0-0.1) mm of the compensating ring; the outer diameter D1 of the compensating ring is calculated according to the deepest Tmax of the unwelded defect, and D1 is equal to or larger than D2+2Tmax=26.9+2 x 1.5=29.9 mm, and the Tmax=1.5 mm is obtained by a pre-welding test; the width d1 of the compensating ring is determined according to the weld width d2 of the early welding test, d1 is larger than or equal to d2, d2=5mm, and d2=5mm is obtained by the early welding test. And fifth and sixth steps, the welding parameters are different for different vacuum electron beam welding devices.

Example 1 summaries:

the pipe fitting welding method provided in embodiment 1 has the following advantages: 1. the welding line of the feed pipe head is full, so that the problem that the welding line is not full is solved, and a machining allowance suitable for a process is reserved after welding; 2. qualified weld joint liquid penetration test and ray detection, good weld joint forming, no defects such as thermal cracks and the like; 3. the external compensating ring releases welding stress, reduces welding deformation, and the welded parent metal pipe fitting does not need to be straightened.

In summary, the present application provides a pipe welding method and a compensating ring applied to pipe welding. And butt-jointing the base metal pipe fittings to be welded end to end, wherein a compensating ring is arranged on the periphery of the butt joint part of the base metal pipe fittings. And performing vacuum electron beam welding at the butt joint of the base metal pipe fittings, and melting the compensation ring together to form a welding line at the butt joint of the base metal pipe fittings. The lowest part of the outer surface of the welding seam is higher than or flush with the outer peripheral surface of the base metal pipe fitting, namely the compensation ring can effectively solve the problem that the welding seam is not fully welded, so that the risk of the welding seam being not fully welded can be reduced. And the compensation ring is melted together in the welding process, namely the welding line is formed by one-step welding, which is beneficial to ensuring the quality of the welding line.

The application has the following advantages:

1. the welding method of the external compensation ring matched with vacuum electron beam welding is adopted for the first time, and is used for solving the problem that the butt welding of nickel-based alloy (such as NS1402, NS3105 and the like) pipe fittings is easy to cause incomplete welding of welding seams. For the problem that the welding seam is not fully welded easily in the butt welding of nickel-based alloy pipe fittings, the quality of the welding seam cannot be ensured due to the adoption of an argon arc welding repair method at present.

2. The welding method of the external compensation ring matched with vacuum electron beam welding is adopted for the first time, so that the butt joint of nickel-based alloy (such as NS1402, NS3105 and the like) pipe fittings is successfully realized, and the butt joint weld has the defects of good formation, no thermal crack and the like. For nickel-based alloy materials, welding is carried out by adopting a fusion welding method such as argon arc welding and the like, and the defects of easiness in occurrence of hot cracks and the like of welding seams are caused by poor welding property, so that the vacuum band electron beam welding is adopted to help avoid the occurrence of the hot cracks.

3. The form of the complete compensation ring is formed by adopting two semi-ring form compensation bodies in vacuum electron beam welding for the first time, the compensation bodies are assembled into the complete compensation ring in a spot welding mode, the compensation ring is conveniently locked at the butt joint of the base metal pipe fitting, straight pipe butt joint, bent pipe butt joint and the like can be realized, and compared with the integral compensation ring, the application range of the compensation ring is wide.

4. A compensation ring with a clamping part of a V-shaped structure is adopted in vacuum electron beam welding for the first time.

5. The originality of the compensation ring installation, the clamping part of the V-shaped structure is matched with the limit groove reserved by the base metal pipe fitting, and the purposes of limiting and centering are achieved.

6. The originality of the compensation ring structure, the cross section shape of the compensation ring is the combination of a rectangle and an isosceles right triangle with the hypotenuse length of 2mm, and the compensation ring has simple structure and is easy to process.

7. The originality of the function of the compensating ring not only has the advantage of leaving suitable process allowance after welding, but also is beneficial to releasing stress in the welding process, reducing welding deformation, and the pipe fitting does not need to be straightened after welding.

8. The originality of the size determining method of the compensating ring, the outer diameter D1, the inner diameter D2 and the width D1 of the compensating ring are obtained according to the size of the base metal pipe fitting and the measurement of a welding test, and the compensating ring has certain flexibility in practical application.

9. The pipe fitting welding method provided by the application is innovative.

10. The application provides a compensating ring compares in built-in liner welded mode, and the problem that built-in liner is difficult to take out after welding can not appear, and the surplus height of compensating ring melting after welding can be got rid of through polishing or machining.

The pipe welding method and the compensating ring applied to pipe welding provided by the application are described in detail, and specific examples are applied to the description of the principles and the implementation modes of the application, and the description of the examples is only used for helping to understand the method and the core idea of the application; meanwhile, as those skilled in the art will have modifications in the specific embodiments and application scope in accordance with the ideas of the present application, the present description should not be construed as limiting the present application in view of the above.

Claims (10)

1. A method of welding a pipe, comprising:

butt-jointing the base metal pipe fittings to be welded end to end, wherein a compensating ring is arranged on the periphery of the butt joint part of the base metal pipe fittings;

and performing vacuum electron beam welding at the butt joint of the base metal pipe fittings, and melting the compensation ring together to form a welding seam at the butt joint of the base metal pipe fittings, wherein the compensation ring is used for enabling the lowest position of the outer surface of the welding seam to be higher than or flush with the outer peripheral surface of the base metal pipe fittings.

2. A pipe welding method according to claim 1, wherein,

the compensation ring includes:

a ring body; and

a clamping part arranged on the ring main body;

the ring main body is used for being annularly arranged on the periphery of the butt joint position of the base metal pipe fitting after the base metal pipe fitting to be welded is subjected to end-to-end butt joint, and the clamping part is used for being clamped at the butt joint position of the base metal pipe fitting; the outer diameter of the ring main body is D1, the inner diameter of the ring main body is D2, and the maximum compensation amount of the welding line is Tmax, wherein D1 is more than or equal to D2+2Tmax.

3. A pipe welding method according to claim 1, wherein,

the compensation ring includes:

a ring body; and

a clamping part arranged on the ring main body;

the ring main body is used for being annularly arranged on the periphery of the butt joint position of the base metal pipe fitting after the base metal pipe fitting to be welded is subjected to end-to-end butt joint, and the clamping part is used for being clamped at the butt joint position of the base metal pipe fitting; the inner diameter of the ring main body is D2, the outer diameter of the parent metal pipe fitting is D3, and D2 is more than or equal to D3.

4. A pipe welding method according to claim 1, wherein,

the width of the compensation ring is d1, and the width of the welding line is d2;

wherein d1 is greater than or equal to d2.

5. A pipe welding method according to any one of claims 1 to 4, wherein,

the compensating ring comprises at least two compensating bodies, and the compensating bodies are sequentially distributed along the circumferential direction of the compensating ring;

the step of butt-jointing the base metal pipe fittings to be welded end to end comprises the following steps:

sequentially mounting the compensation bodies on the periphery of the butt joint part of the base metal pipe fitting;

and performing spot welding fixation at the butt joint of the adjacent compensation bodies.

6. A pipe welding method according to any one of claims 1 to 4, wherein,

the step of vacuum electron beam welding at the butt joint of the base metal pipe fittings comprises the following steps:

controlling an electron beam gun head to uniformly spot-weld the compensation ring along the circumferential direction of the compensation ring;

calibrating the relative positions of the electron beam gun head and the parent metal pipe fitting through a spot welding track, so that the electron beam gun head is aligned to the center of the compensation ring;

controlling the electron beam gun head to continuously weld the compensation ring along the circumferential direction of the compensation ring;

and calibrating the relative positions of the electron beam gun head and the base metal pipe fitting through continuous welding tracks, so that the electron beam gun head is aligned to the center of the compensation ring.

7. A pipe welding method according to any one of claims 1 to 4, wherein,

the step of vacuum electron beam welding at the butt joint of the base metal pipe fitting comprises the following steps:

and carrying out vacuum electron beam welding on the butt joint of the base metal pipe fitting by adopting preset welding parameters, wherein the preset welding parameters are matched with the sum of the thickness of the pipe wall of the base metal pipe fitting and the ring thickness of the compensation ring.

8. A pipe welding method according to claim 1, wherein,

the step of butt-jointing the base metal pipe fittings to be welded end to end comprises the following steps:

a groove is processed at the end part of the parent metal pipe fitting, so that the grooves of the adjacent parent metal pipe fittings are matched to form a limit groove after the parent metal pipe fittings are in butt joint;

the compensation ring comprises a ring main body and a clamping part, wherein the clamping part is convexly arranged on the inner side of the ring main body, and the clamping part is used for being clamped in the limiting groove after the ring main body is annularly arranged on the periphery of the butt joint part of the base metal pipe fitting.

9. A pipe welding method according to any one of claims 1 to 4, wherein,

the step of butt-jointing the base metal pipe fittings to be welded end to end comprises the following steps:

butt-jointing the base metal pipe fittings end to end, and spot-welding and assembling the butt-jointed parts of the base metal pipe fittings; wherein the assembly gap between adjacent parent metal pipe fittings is less than or equal to 0.05mm.

10. A compensating ring for pipe fitting welding, the compensating ring comprising:

a ring body; and

a clamping part arranged on the ring main body;

the ring main body is used for being annularly arranged on the periphery of the butt joint position of the base metal pipe fitting after the base metal pipe fitting to be welded is subjected to end-to-end butt joint, and the clamping part is used for being clamped at the butt joint position of the base metal pipe fitting; and the compensation ring is melted together when the butt joint of the base metal pipe fittings is subjected to vacuum electron beam welding so as to form a welding line at the butt joint of the base metal pipe fittings, wherein the compensation ring is used for enabling the lowest position of the outer surface of the welding line to be higher than or flush with the outer peripheral surface of the base metal pipe fittings.

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