JP5851694B2 - Cylindrical weld forming method and welding apparatus - Google Patents

Description

  The present invention relates to a cylindrical part welding forming method and welding apparatus for forming a cylindrical part protruding from a welding surface by overlay welding.

  2. Description of the Related Art Conventionally, a build-up welding method is known in which build-up welding is performed on a nozzle by controlling a turning table that holds and rotates and tilts a nozzle to be welded and a welding head that performs welding on the nozzle. (For example, refer to Patent Document 1).

JP-A-1-178371

  However, in the conventional overlay welding method, the welding object must be rotated (turned). For this reason, when a welding target object is a big structure which is hard to move, for example, it is difficult to perform predetermined welding to a welding target object. In particular, when a cylindrical portion having a predetermined thickness is formed on the welding surface of the welding object by overlay welding, it is difficult to perform efficient welding when the welding object is rotated.

  Then, this invention makes it a subject to provide the cylindrical part welding formation method and welding apparatus which can perform overlay welding efficiently, when forming a cylindrical part in a welding surface.

  The cylindrical part weld formation method of the present invention is a cylindrical part weld formation method in which a cylindrical part protruding from a welding surface is formed by overlay welding, and the axial direction of the formed cylindrical part is the protruding direction of the cylindrical part. It is a spiral buildup that performs overlay welding in a spiral shape on the welding surface by moving in the radial direction of the cylindrical portion while rotating around the cylindrical portion around the axis of the formed cylindrical portion A welding process is provided.

  According to this configuration, when forming a cylindrical portion having a predetermined thickness by overlay welding in the spiral overlay welding process, overlay welding can be performed in a spiral shape. For this reason, in the spiral overlay welding process, overlay welding can be performed without moving the welding surface, and overlay welding can be performed without interruption. Thereby, a cylindrical part can be efficiently formed with respect to a welding surface.

  In this case, before the spiral overlay welding process, flat welding is performed on the welding surface so that the welding surface becomes flat while rotating around the cylindrical portion in the circumferential direction around the axis of the cylindrical portion to be formed. It is preferable to further include an overlay welding process.

  According to this structure, when a welding surface is not flat, a welding surface can be made flat in a flat overlay welding process. Thereby, in the spiral overlay welding process, spiral overlay welding can be suitably performed on a flat weld surface.

  In this case, the welding surface is the outer peripheral surface of a cylindrical container that is point-symmetrical about the axis of the cylindrical portion, and in the flat overlay welding process, welding is performed so that it is point-symmetrical about the axis of the cylindrical portion. It is preferable to perform overlay welding on the surface.

  According to this configuration, in the flat overlay welding process, the outer peripheral surface is easily flattened by performing overlay welding so that the cylindrical outer peripheral surface is point-symmetrical about the axis of the cylindrical portion. be able to.

  In this case, a cylindrical tube welding step for welding the cylindrical tube is further provided before the spiral overlay welding step, and in the cylindrical tube welding step, the axial center of the cylindrical tube to be welded is coaxial with the axial center of the formed cylindrical portion. It is preferable to weld the cylindrical tube to the welding surface so as to be on top.

  According to this configuration, the spiral overlay welding process can be performed in a state where the cylindrical tube is welded on the same axis of the formed cylindrical portion. That is, in the spiral build-up welding process, build-up welding is performed in a spiral shape with the cylindrical tube serving as the inner wall of the cylindrical portion. For this reason, in the spiral build-up welding process, it is not necessary to perform build-up welding at the axial center of the cylindrical portion, so that build-up welding can be performed efficiently. Moreover, the cylindrical tube can suppress welding sag toward the axial center of the cylindrical portion.

  The welding apparatus of the present invention is a welding apparatus for forming a cylindrical portion protruding from a welding surface by overlay welding, and the axial direction of the formed cylindrical portion is a protruding direction of the cylindrical portion, and the welding surface A welding head that performs welding toward the welding head, a filler material supply part that supplies a filler material toward the welding head, and a moving mechanism that can move the welding head in the circumferential direction and the radial direction of the formed cylindrical part, A control unit capable of controlling the moving mechanism, and the control unit moves in the radial direction of the cylindrical portion while rotating the welding head around the axis of the formed cylindrical portion in the circumferential direction of the cylindrical portion. By doing so, it is possible to execute spiral build-up welding control in which weld welding is performed in a spiral shape on the welding surface.

  According to this configuration, when the cylindrical portion having a predetermined thickness is formed by overlay welding, the overlay welding can be performed in a spiral shape by the spiral overlay welding control. For this reason, by performing spiral build-up welding control, build-up welding can be performed without moving the welding surface, and build-up welding can be performed without interruption. Thereby, a cylindrical part can be efficiently formed with respect to a welding surface.

  In this case, the control unit is formed on the welding surface so as to be point-symmetric about the axis of the cylindrical portion while rotating the welding head in the circumferential direction of the cylindrical portion around the axis of the formed cylindrical portion. It is preferable that point symmetric overlay welding control for performing overlay welding can be executed.

  According to this configuration, build-up welding can be performed on a welding surface that is point-symmetric about the axis of the cylindrical portion by point-symmetric build-up welding control. For this reason, for example, when flattening a cylindrical outer peripheral surface that is point-symmetrical about the axis of the cylindrical portion, by performing point-symmetric overlay welding control, By performing overlay welding so as to be point-symmetric about the axis, the outer peripheral surface can be easily flattened.

  According to the cylindrical part welding formation method and welding apparatus of the present invention, when forming a cylindrical part on the welding surface, overlay welding can be performed in a spiral shape, so that overlay welding can be performed efficiently.

FIG. 1 is a front view of a pressure vessel to be welded by the welding apparatus according to the present embodiment. FIG. 2 is a cross-sectional view of the pressure vessel cut along a plane orthogonal to the axial direction. FIG. 3 is a partial cross-sectional view of a cylindrical portion serving as a basis of the cylindrical window, cut by a plane orthogonal to the axial direction of the pressure vessel. FIG. 4 is a front view of the welding apparatus according to the present embodiment. FIG. 5 is an explanatory diagram when the welding operation of the welding apparatus by flat overlay welding control is viewed in plan. FIG. 6 is an explanatory diagram when the welding operation of the welding apparatus by the spiral overlay welding control is viewed in plan. FIG. 7 is an explanatory diagram illustrating a first pipe welding process and a flat overlay welding process of the cylindrical part welding forming method according to the present embodiment. FIG. 8 is an explanatory diagram when the welding operation of the welding apparatus in the flat overlay welding process is viewed from the cross-sectional side. FIG. 9 is an explanatory diagram showing a spiral overlay welding process of the cylindrical part welding forming method according to the present embodiment. FIG. 10 is an explanatory diagram when the welding operation of the welding apparatus in the spiral overlay welding process is viewed from the cross-sectional side. FIG. 11 is an explanatory diagram illustrating a build-up process of the cylindrical part weld forming method according to the present embodiment. FIG. 12 is an explanatory diagram illustrating a second pipe welding process of the cylindrical part welding forming method according to the present embodiment. FIG. 13 is an explanatory diagram illustrating a cladding welding process of the cylindrical part welding forming method according to the present embodiment.

  Hereinafter, with reference to the attached drawings, a cylindrical part welding forming method and a welding apparatus according to the present invention will be described. The present invention is not limited to the following examples. In addition, constituent elements in the following embodiments include those that can be easily replaced by those skilled in the art or those that are substantially the same.

  The cylindrical part welding formation method according to the present embodiment is a method of forming a cylindrical part by performing overlay welding on the welding surface of the container. This cylindrical part welding forming method is performed using a welding apparatus, and a vessel to be welded is, for example, a pressure vessel of a steam generator used in a pressurized water nuclear reactor. In addition, although the cylindrical part welding formation method and welding apparatus of a present Example are applied and demonstrated to a pressure vessel as a container, you may apply not only to a pressure vessel but to any container. Hereinafter, the pressure vessel to be welded will be described with reference to FIGS. 1 to 3.

  FIG. 1 is a front view of a pressure vessel to be welded by the welding apparatus according to the present embodiment, FIG. 2 is a cross-sectional view of the pressure vessel taken along a plane orthogonal to the axial direction, and FIG. It is sectional drawing which cut the cylindrical part used as the foundation of a window with the surface orthogonal to the axial direction of a pressure vessel. In the pressure vessel 1, the upper portion in the vertical direction is a thick upper shell, and the lower portion in the vertical direction is a thin lower shell. The middle part between the upper part and the lower part of the pressure vessel 1 is formed in a tapered shape that tapers from the upper side toward the lower side.

  The upper shell of the pressure vessel 1 has a cylindrical window 5 used for monitoring the inside of the pressure vessel 1, inspecting the inside of the pressure vessel 1, and detecting the state of the inside of the pressure vessel 1. A plurality of pressure vessels 1 are provided in the circumferential direction. In the present embodiment, four cylindrical windows 5 are provided. The four cylindrical windows 5 are provided at equal intervals by shifting the phase by 90 ° in the circumferential direction. The cylindrical window 5 is provided so as to protrude from the outer peripheral surface 1 a of the pressure vessel 1, and the protruding direction of the cylindrical window 5 is the axial direction of the cylindrical window 5.

  The cylindrical window 5 is formed by a welding device 20 and a cylindrical part welding forming method, which will be described later, with the cylindrical part 5a serving as a foundation. And the cylindrical window 5 is comprised by attaching a window material etc. to the formed cylindrical part 5a. As shown in FIG. 3, the cylindrical portion 5 a includes a first build-up portion 10 that is build-up welded to the outer peripheral surface 1 a of the pressure vessel 1, and a second build-up weld that is build-up welded to the first build-up portion 10. And a through-hole 12 that penetrates the pressure vessel 1, the first build-up part 10, and the second build-up part 11.

  The first build-up portion 10 is formed in a cylindrical shape, and the outer peripheral surface 10a on the axial pressure vessel side (the lower side in the drawing) is formed into a curved surface that is convex toward the through-hole 12 side. The second build-up part 11 is formed in a cylindrical shape, and is provided coaxially with the first build-up part 10. The diameter of the second build-up part 11 is smaller than the diameter of the first build-up part 10. The first build-up part 10 is made of the same material as the pressure vessel 1, and the second build-up part 11 is made of a material different from the first build-up part 10. The through-hole 12 has a circular cross section, and penetrates the pressure vessel 1 while passing through the axial center of the cylindrical portion 5a, that is, the axial centers of the first and second built-up portions 10 and 11. It is formed. The through-hole 12 has a chamfered inner edge of the pressure vessel 1.

  Next, with reference to FIG. 4, the welding apparatus 20 used in order to form the cylindrical part 5a is demonstrated. FIG. 4 is a front view of the welding apparatus according to the present embodiment. The welding apparatus 20 is configured to be able to perform submerged arc welding. The welding device 20 is attached to a frame (not shown), and includes a welding head 21 that performs welding, a wire reel (a filler material supply unit) 22 that supplies a welding wire (a filler material) toward the welding head 21, and A hopper 23 that supplies flux toward the welding head 21, a moving mechanism 24 that moves the welding head 21, and a control unit 25 that controls them are provided. In addition, although a present Example demonstrates and applies to submerged arc welding, it is not limited to this, It can apply also to automatic welding, such as automatic TIG welding, automatic MIG welding, and automatic MAG welding.

  The welding head 21 feeds the supplied welding wire from the tip, and generates an arc between the welding wire fed from the tip and the welding surface. The welding head 21 is provided with a head angle adjustment mechanism 28 that adjusts the welding angle with respect to the welding surface of the welding head 21, and the welding angle of the welding head 21 with respect to the welding surface is appropriately set by the head angle adjustment mechanism 28. Adjusted.

  The wire reel 22 appropriately supplies a welding wire according to welding by the welding head 21. The hopper 23 stores the flux therein and supplies the flux in advance of the welded portion of the welding head 21.

  The moving mechanism 24 moves the welding head 21 in the θ direction, the Y direction, and the Z direction, and includes a θ axis moving mechanism 31, a Y axis moving mechanism 32, and a Z axis moving mechanism 33. The θ-axis moving mechanism 31 is attached to the frame and can rotate the welding head 21 in the θ direction. When the cylindrical portion 5a is formed, the welding head 21 is rotated in the circumferential direction of the cylindrical portion 5a. Can do. The Y-axis moving mechanism 32 is attached to the θ-axis moving mechanism 31 and can move the welding head 21 in the Y direction. When forming the cylindrical portion 5a, the welding head 21 is moved in the radial direction of the cylindrical portion 5a. Can be moved to. The Z-axis moving mechanism 33 is attached to the Y-axis moving mechanism 32 and can move the welding head 21 in the Z direction. When forming the cylindrical portion 5a, the welding head 21 is moved in the axial direction of the cylindrical portion 5a. Can be moved to.

  The controller 25 adjusts the supply amount of the welding wire supplied toward the welding head 21 and controls the movement of the welding head 21 by the moving mechanism 24. The control unit 25 includes a θ-axis sensor 35 that detects a rotation angle in the θ direction, a Y-axis sensor 36 that detects a movement amount in the Y direction, and a Z-axis sensor 37 that detects a movement amount in the Z direction. Is connected. Then, the control unit 25 controls the θ-axis moving mechanism 31, the Y-axis moving mechanism 32, and the Z-axis moving mechanism 33 based on detection by the θ-axis sensor 35, the Y-axis sensor 36, and the Z-axis sensor 37, respectively. .

  Accordingly, the welding apparatus 20 appropriately controls the movement of the welding head 21 by the moving mechanism 24 while adjusting the supply amount of the welding wire supplied to the welding head 21 by controlling each part by the control unit 25. Thus, predetermined welding can be performed on the welding surface. Here, the control part 25 is comprised so that execution of point symmetrical overlay welding control and spiral overlay welding control is possible. Hereinafter, with reference to FIG. 5 and FIG. 6, the point-symmetric overlay welding control and the spiral overlay welding control will be described.

  FIG. 5 is an explanatory diagram when the welding operation of the welding apparatus by flat overlay welding control is viewed from the plane side, and FIG. 6 is when the welding operation of the welding apparatus by spiral overlay welding control is viewed from the plane side. It is explanatory drawing of. As shown in FIG. 5, the point-symmetric overlay welding control is performed by rotating (moving) the welding head 21 in the circumferential direction (θ direction) of the cylindrical portion 5a with respect to the formed cylindrical portion 5a. In this control, overlay welding is performed so as to be point-symmetric about the axis.

  Here, the outer peripheral surface 1a of the pressure vessel 1 to be welded is 180 ° symmetrical with respect to the axis of the formed cylindrical portion 5a. That is, on the circumferential center line L1 of the pressure vessel 1 that passes through the axial center P of the cylindrical portion 5a, the outer peripheral surface 1a of the pressure vessel 1 becomes farther away from the axial center P of the cylindrical portion 5a. Side). Further, on the axial center line L2 of the pressure vessel 1 passing through the axial center P of the cylindrical portion 5a, the outer peripheral surface 1a of the pressure vessel 1 has the same height as the surface at the axial center P of the cylindrical portion 5a. At this time, in order to flatten the outer peripheral surface 1a of the pressure vessel 1, build-up welding is performed on a pair of flat build-up regions E1 that are symmetric with respect to 180 ° about the axis of the cylindrical portion 5a. The flat overlay region E1 is an arc-shaped region centered on the center line L1.

  Thus, the outer peripheral surface 1a of the pressure vessel 1 to be welded is not flat, and the point-symmetric build-up welding control is executed to make the outer peripheral surface 1a of the pressure vessel 1 flat. When the point-symmetric overlay welding control is executed, the welding apparatus 20 moves the welding head 21 by a predetermined angle θ with respect to the outer peripheral surface 1a sandwiching the center line L2 to overlay the flat overlay region E1. Welding is performed, and thereafter, the welding head 21 is circulated, and the welding head 21 is moved by a predetermined angle θ to the other outer peripheral surface 1a sandwiching the center line L2, and overlay welding is performed in the flat overlay region E1. . In other words, the welding start position S1 of the welding head 21 on the outer peripheral surface 1a on one side and the welding start position S2 of the welding head 21 on the outer peripheral surface 1a on the other side are symmetric with respect to 180 °. The welding end position T1 of the welding head 21 on the outer peripheral surface 1a on one side and the welding end position T2 of the welding head 21 on the outer peripheral surface 1a on the other side are symmetrical by 180 °.

  As shown in FIG. 6, the spiral build-up welding control is performed by rotating (moving) the welding head 21 in the circumferential direction (θ direction) of the cylindrical portion 5a with respect to the formed cylindrical portion 5a. It is control which moves in the direction (Y direction) and performs overlay welding in a spiral shape. The spiral build-up welding control is executed to form the first build-up portion 10 of the cylindrical portion 5 a with respect to the pressure vessel 1. In the spiral build-up welding control, build-up welding is performed on the spiral build-up region E <b> 2 that is substantially flat and necessary for forming the first build-up portion 10. The spiral build-up area E2 is a circular area centered on the axis of the cylindrical portion 5a.

  When the spiral build-up welding control is executed, the welding apparatus 20 causes the welding head 21 to make one round in the circumferential direction on the radially inner side of the cylindrical portion 5a to be formed. After welding, the welding head 21 is moved to the outer peripheral side in the radial direction of the cylindrical portion 5a, so that the welding head 21 makes one round in the circumferential direction and is welded all around. When performing all-around welding, the welding head 21 forms an overlap portion 40 where the start end side and the rear end side of overlay welding overlap, and after the formation of the overlap portion 40, the welding head 21 is formed on the radially outer side of the cylindrical portion 5 a. Moving. And the welding apparatus 20 performs build-up welding in a spiral shape until the entire region of the spiral build-up region E2 is build-up welded.

  Next, with reference to FIG. 7 thru | or FIG. 13, the cylindrical part welding formation method using the welding apparatus 20 is demonstrated. In the cylindrical part welding forming method, a first pipe welding process (cylindrical pipe welding process), a flat overlay welding process, a spiral overlay welding process, an overlaying process, a second pipe welding process, and a cladding welding process. And the cylindrical portion processing step are sequentially performed.

  FIG. 7 is an explanatory diagram illustrating a first pipe welding process and a flat overlay welding process of the cylindrical part welding forming method according to the present embodiment. As shown in FIG. 7, the first pipe welding step is a step of welding a first pipe (cylindrical tube) 50 to the outer peripheral surface 1 a of the pressure vessel 1. In the first pipe welding step, the first pipe 50 is welded to the outer peripheral surface 1a so that the axial direction of the first pipe 50 is the protruding direction of the cylindrical portion 5a that protrudes with respect to the outer peripheral surface 1a. At this time, welding is performed such that the axial center of the first pipe 50 is coaxial with the axial center of the formed cylindrical portion 5a.

  The flat build-up welding process is a process of executing point-symmetric build-up welding control and flattening the outer peripheral surface 1 a of the pressure vessel 1 by the welding device 20. The outer peripheral surface 1a of the pressure vessel 1 is a curved surface that curves in the circumferential direction of the pressure vessel 1 with the center line L2 interposed therebetween. For this reason, in the flat overlay welding process, the outer peripheral surface 1a curved in the circumferential direction of the pressure vessel 1 is flattened across the center line L2. At this time, in the flat overlay welding process, overlay welding is performed while the welding head 21 of the welding apparatus 20 is rotated in the circumferential direction of the cylindrical portion 5a.

  In the flat overlay welding process, welding is performed by moving the welding head 21 of the welding device 20 to the outer peripheral surface 1a on one side across the center line L2 by a predetermined angle θ, and thereafter the welding head 21 is turned around. Then, welding is performed by moving the other side outer peripheral surface 1a across the center line L2 by a predetermined angle θ. That is, in the flat build-up welding process, the welding head 21 is moved from the welding start position S1 to the welding end position T1 on the outer peripheral surface 1a on one side, and then the welding head 21 is circulated and the other side is turned. Overlay welding is performed by moving the welding head 21 from the welding start position S2 to the welding end position T2 of the outer peripheral surface 1a. In the flat build-up welding process, point-symmetric build-up welding control is executed a plurality of times on the flat build-up region E1 until the outer peripheral surface 1a of the pressure vessel 1 becomes flat.

  FIG. 8 is an explanatory diagram when the welding operation of the welding apparatus in the flat overlay welding process is viewed from the cross-sectional side. As shown in FIG. 8, in the flat build-up welding process, for example, the build-up welding is performed on the flat build-up region E <b> 1 by performing point-symmetric build-up welding control five times. In the first point-symmetric overlay welding control, overlay welding is performed at the first position I1, which is the outermost peripheral side of the flat overlay region E1, and in the second point-symmetric overlay welding control, the inner circumference of the first position I1 is achieved. Overlay welding is performed at the second position I2 on the side. In the third point symmetric build-up welding control, build-up welding is performed at the third position I3 that is axially outside the first position I1, and in the fourth point symmetric build-up welding control, the inner peripheral side of the third position I3. Overlay welding is performed at the fourth position I4. In the fifth point-symmetric overlay welding control, overlay welding is performed at the fifth position I5 which is the inner peripheral side of the fourth position I4.

  FIG. 9 is an explanatory diagram showing a spiral overlay welding process of the cylindrical part welding forming method according to the present embodiment. As shown in FIG. 9, in the spiral build-up welding process, the spiral build-up welding control is executed, and the welding device 20 forms the first build-up portion 10 of the cylindrical portion 5 a on the outer peripheral surface 1 a of the pressure vessel 1. It is a process. In the spiral build-up welding process, the outer circumference of the pressure vessel 1 is moved by moving the welding head 21 of the welding device 20 from the inner side to the outer side in the radial direction of the cylindrical portion 5a while rotating in the circumferential direction of the cylindrical portion 5a. Overlay welding is performed on the surface 1a in a spiral shape. That is, in the spiral build-up welding process, on the outer peripheral side of the welded first pipe 50, the welding head 21 is made to make one turn in the circumferential direction, and then the entire circumference is welded. By moving to the outside in the radial direction and repeating this, build-up welding is performed on the spiral build-up region E2. In the spiral build-up welding process, the spiral build-up welding control is executed a plurality of times until the height of the cylindrical portion 5a in the axial direction (Z direction) reaches a predetermined height.

  FIG. 10 is an explanatory diagram when the welding operation of the welding apparatus in the spiral overlay welding process is viewed from the cross-sectional side. As shown in FIG. 10, in the spiral build-up welding process, the first layer build-up welding is performed by spirally welding the spiral build-up region E2 from the inside to the outside of the cylindrical portion 5a. Form. In the spiral build-up welding process, build-up welding is formed over a plurality of layers until the height of the cylindrical portion 5a reaches a predetermined height.

  FIG. 11 is an explanatory diagram illustrating a build-up process of the cylindrical part weld forming method according to the present embodiment. As shown in FIG. 11, the build-up process is a process of forming a circular groove 52 by machining on the end surface on the outer side in the axial direction of the first build-up portion 10 formed by the spiral build-up welding process. Here, the formed circular groove 52 has a diameter that is approximately half the diameter of the first build-up portion 10, and the first pipe 50 and the first build-up are centered on the axis of the cylindrical portion 5a. A part of the part 10 is formed in a circular shape.

  FIG. 12 is an explanatory diagram illustrating a second pipe welding process of the cylindrical part welding forming method according to the present embodiment. As shown in FIG. 12, the second pipe welding step is a step of welding the second pipe 54 surrounding the circular groove 52 formed by the build-up processing step to the end surface on the outer side in the axial direction of the first build-up portion 10. is there. In the second pipe welding step, the second pipe 54 is connected to the axially outer end surface of the first build-up portion 10 so that the axial center of the second pipe 54 is coaxial with the axial center of the formed cylindrical portion 5a. Weld to. In the second pipe welding process, a circular lid 56 is attached to the opening on the outer side in the axial direction of the first pipe 50.

  FIG. 13 is an explanatory diagram illustrating a cladding welding process of the cylindrical part welding forming method according to the present embodiment. As shown in FIG. 13, the clad welding process is a process of forming the second built-up portion 11 on the end surface on the axially outer side of the first built-up portion 10. That is, in the clad welding process, the second built-up portion 11 is formed by performing build-up welding on the circular groove 52 inside the second pipe 54. In the cladding welding process, build-up welding is performed until the height of the second build-up portion 11 in the axial direction reaches a predetermined height. The clad welding process may be performed using the welding apparatus 20 or may be performed manually without using the welding apparatus 20.

  In the cylindrical portion processing step, the first built-up portion 10 and the second built-up portion 11 formed by the above steps are processed into a predetermined shape to form a cylindrical portion 5a shown in FIG. Specifically, in the cylindrical part machining step, the through-hole 12 that communicates the outside and the inside of the pressure vessel 1 is formed at the axial center of the cylindrical part 5a, and the first and second build-up parts 10 and 2 are built up. The part 11 is formed into a predetermined shape by gouging. The diameter of the formed through-hole 12 is larger than the diameter of the first pipe 50 and smaller than the diameter of the second built-up portion 11. Further, the second built-up portion 11, the first built-up portion 10, the first pipe 50, and the pressure vessel 1 are machined so that the axial center of the through-hole 12 is coaxial with the axial center of the cylindrical portion 5a. To form through. Further, the edge of the through-hole 12 on the pressure vessel side is chamfered. The outer peripheral surface 10a of the first build-up portion 10 is formed in a curved surface in which the axial pressure vessel side is convex toward the through-hole side, and the second second build-up portion side (upper side in the drawing) is formed in a cylindrical shape. Is done. The outer peripheral surface 11 a of the second build-up portion 11 is formed in a cylindrical shape so as to remove the second pipe 54.

  By performing each process in order as described above, the cylindrical portion 5a serving as the basis of the cylindrical window 5 can be formed on the outer peripheral surface 1a of the pressure vessel 1. And the cylindrical window 5 is comprised by attaching window material etc. to the formed cylindrical part 5a.

  As described above, according to the cylindrical part welding forming method and the welding apparatus 20 of the present embodiment, in the spiral build-up welding process, the spiral build-up welding control is executed, and the overlay welding is performed in a spiral shape. The first build-up portion 10 of the cylindrical portion 5a can be formed. For this reason, in a spiral build-up welding process, build-up welding can be performed without moving the outer peripheral surface 1a of the pressure vessel 1, and build-up welding can be performed without interruption. Thereby, in the spiral build-up welding process, the first build-up portion 10 of the cylindrical portion 5a can be efficiently formed on the outer peripheral surface 1a of the pressure vessel 1.

  Further, before the spiral build-up welding process, the point-symmetric welding control is executed in the flat build-up welding process so that the outer peripheral surface 1a of the pressure vessel 1 is point-symmetric about the axis of the cylindrical portion 5a. By performing overlay welding, the outer peripheral surface 1a of the pressure vessel 1 can be easily flattened. Further, in the spiral build-up welding process, spiral build-up welding can be suitably performed on the outer peripheral surface 1a that has become flat.

  In addition, the first pipe 50 is welded to the outer peripheral surface 1a of the pressure vessel 1 in the first pipe welding process before the spiral build-up welding process, so that the shaft of the cylindrical portion 5a is formed in the spiral build-up welding process. Since it is not necessary to perform overlay welding at the center, overlay welding can be performed efficiently. Moreover, the 1st pipe 50 can suppress the welding sag which goes to the axial center of the cylindrical part 5a by the build-up welding of a spiral build-up welding process.

  As described above, the cylindrical part welding forming method and welding apparatus according to the present invention are useful in the case of forming a cylindrical part by overlay welding, and are particularly suitable for welding a pressure vessel of a steam generator. .

DESCRIPTION OF SYMBOLS 1 Pressure vessel 5 Cylindrical window 5a Cylindrical part 10 1st build-up part 11 2nd build-up part 12 Through-hole 20 Welding device 21 Welding head 22 Wire reel 23 Hopper 24 Moving mechanism 25 Control part 40 Overlap part 50 1st pipe 52 Circular groove 54 Second pipe 56 Lid E1 Flat overlay area E2 Spiral overlay area

Claims (8)

A cylindrical part welding forming method for forming a cylindrical part protruding from a welding surface by overlay welding,
The axial direction of the formed cylindrical part is the protruding direction of the cylindrical part,
A spiral overlay that performs overlay welding in a spiral manner on the welding surface by moving in the radial direction of the cylindrical portion while rotating in the circumferential direction of the cylindrical portion around the axis of the cylindrical portion to be formed With a welding process ,
In the spiral build-up welding process, the radially inner side of the cylindrical portion is made to make one round in the circumferential direction, and the radially inner peripheral side of the cylindrical portion is welded all around, and then moved to the outer peripheral side in the direction of the cylindrical portion. A cylindrical part welding forming method characterized in that the radially outer side of the cylindrical part is made to make one round in the circumferential direction and the radially outer peripheral side of the cylindrical part is welded all around .   2. The cylindrical part welding formation according to claim 1, wherein in the spiral build-up welding process, an overlap part is formed in which the start end side and the rear end side of the build-up welding overlap during the entire circumference welding. Method. Prior to the spiral overlay welding process, overlay welding is performed on the welding surface so that the welding surface becomes flat while rotating around the axis of the cylindrical portion to be formed in the circumferential direction of the cylindrical portion. cylindrical portion welded forming method according to claim 1 or 2, further comprising a flat overlay welding step of performing. The weld surface is an outer peripheral surface of a cylindrical container that is point-symmetric about the axis of the cylindrical portion,
4. The cylindrical part welding forming method according to claim 3 , wherein, in the flat overlay welding process, overlay welding is performed on the welding surface so as to be point-symmetric about the axis of the cylindrical part. Before the spiral overlay welding process, further comprising a cylindrical pipe welding process of welding the cylindrical pipe,
In the cylindrical tube welding step, the cylindrical tube is welded to the welding surface so that an axial center of the cylindrical tube to be welded is coaxial with an axial center of the formed cylindrical portion. The cylindrical part welding formation method of any one of Claims 1 thru | or 4 . A welding device for forming a cylindrical portion protruding from a welding surface by overlay welding,
The axial direction of the formed cylindrical part is the protruding direction of the cylindrical part,
A welding head for performing welding toward the welding surface;
A filler material supply section for supplying a filler material toward the welding head;
A moving mechanism capable of moving the welding head in a circumferential direction and a radial direction of the cylindrical portion to be formed;
A control unit capable of controlling the moving mechanism,
The control unit swirls around the welding surface by moving the welding head in the radial direction of the cylindrical part while rotating the welding head around the axis of the cylindrical part to be formed. Jo to run the spiral overlay welding control for overlay welding,
In the spiral build-up welding control, the radially inner side of the cylindrical portion is made to make one round in the circumferential direction, and the radially inner peripheral side of the cylindrical portion is welded all around, and then moved to the outer peripheral side in the direction of the cylindrical portion. A welding apparatus characterized in that the radially outer side of the cylindrical part is made to make one round in the circumferential direction and the radially outer peripheral side of the cylindrical part is welded all around .   The welding apparatus according to claim 6, wherein, in the spiral build-up welding control, an overlap portion is formed in which the start end side and the rear end side of the build-up welding overlap during the entire circumference welding. The control unit is configured so that the welding head is symmetric about the axis of the cylindrical part while rotating the welding head in the circumferential direction of the cylindrical part about the axis of the cylindrical part to be formed. The welding apparatus according to claim 6 or 7 , wherein point-symmetric build-up welding control for performing build-up welding on a surface is executable.

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