JP5989860B2 - Vacuum container manufacturing method - Google Patents

Description

  The present invention relates to a general vacuum vessel and a method for manufacturing a vacuum vessel such as a waveguide used in an accelerator system.

  A waveguide used in an accelerator system or the like is a device for transmitting high-frequency power, and the inside thereof is kept in a vacuum, and is required to transmit high power without causing power loss or discharge.

  A conventional waveguide manufacturing method will be described with reference to FIGS. As a material of the waveguide, a material having high thermal conductivity and electrical conductivity such as copper is used. When manufacturing large-diameter waveguides using such materials, TIG (Tungsten Inert Gas) welding and MIG (Metal Inert Gas) welding are multilayer welding due to the plate thickness, resulting in a large heat input. Will increase the distortion. For this reason, for the reason that it is relatively inexpensive, has low distortion, and is of high quality, a method in which the upper and lower plates 1 and a pair of side plates 2 are combined and joined by electron beam welding as shown in FIG. It has been adopted.

  However, in this method, the spatter 15 is scattered and adhered to the inner surface side of the waveguide as shown in FIG. 10, the opening 16 is generated at the corner as shown in FIG. 11, or as shown in FIG. There were problems such as distortion of the entire waveguide. For this reason, it is necessary to correct the waveguide after electron beam welding, and work is done to improve the smoothness and shape accuracy of the inner surface by taking care of the inner surface with a file, etc., but in terms of quality and cost There was a problem.

On the other hand, various welding methods as shown in Patent Documents 1 to 3 have been proposed as methods other than electron beam welding.
For example, in Patent Document 1, friction stir welding is used, but this method has a disadvantage in that there is a limitation on the product shape because strong fixation is required at the time of joining. In addition, a backing is required for friction stir welding, but the possibility of damaging the inner surface of the waveguide is increased when the backing is installed on the inner surface side of the waveguide. Furthermore, since a backing that matches the shape is required, a highly accurate manufacturing process is required, and the cost is increased.

  Moreover, although the manufacturing method by plating is used in Patent Document 2, with such a structure, the plating cannot withstand a load caused by a long-time operation, and peeling occurs, which becomes a cause of discharge.

  Further, in Patent Document 3, a drawing method and a broaching method are used. However, in this method, since it is necessary to manufacture a blade used in broaching, it is expensive in a small amount of manufacturing, and only a linear shape can be used. Lack. Furthermore, the use of oil in vacuum equipment is a problem in quality, so the use of oil is not preferred. However, the machinability is greatly reduced, so that a smooth surface cannot be expected depending on the material of the work.

  Waveguides are also manufactured by other methods such as extrusion, but in this case, the range of use is limited, such as those with a small plate thickness, small diameter and linear shape, and high power that is required in high-frequency accelerating cavities etc. Not suitable for transmission.

  Further, in a general vacuum vessel manufacturing method, for example, when welding a thick plate (plate thickness of about 85 mm) invar material or the like to form a vessel shape, electron beam welding or laser welding is performed from the outside of the vessel as shown in FIG. In general, the inner surface of the container is sealed by TIG welding or the like.

  However, in this method, the inner surface side is welded and the cost is increased, and there is a risk of damaging the container when the inner surface side is welded. For this reason, it is desirable to weld from one direction on the outer surface side and form a smooth back surface without scattering due to sputtering. However, for metals with a high molten metal viscosity such as invar material, a groove shape or plate as shown in FIG. It was very difficult with the construction method using the assembly structure.

JP 2001-237621 A Japanese Patent Laid-Open No. 7-58527 JP-A-8-213812

  The problem in manufacturing a vacuum vessel such as a waveguide by welding using the above-described TIG welding, MIG welding, electron beam welding, etc. will be described in more detail.

When a waveguide is manufactured by melt bonding, there are three main reasons for the problems.
The first is distortion of the entire waveguide. The plate is distorted during heating and cooling due to heat input by melt bonding. Accordingly, there is a problem that high dimensional accuracy and shape accuracy required for the waveguide cannot be obtained. For this reason, when the completed waveguide is used as a combinational circuit, measures such as adjustment of the thickness of the gasket and correction of the waveguide are taken and time is used for alignment.

  Secondly, the spatter generated by melt bonding adheres to the inner surface side of the waveguide, thereby causing an abrupt shape change and causing discharge. In addition, when a back wave with many discontinuities or shape changes appears on the inner surface of the waveguide, it also causes discharge. In the waveguide, the problem of the smoothness of the inner surface is a very important problem.

  The third is the opening on the inner surface of the waveguide, which occurs due to insufficient welding fusion or defective shape of the groove. This not only causes discharge but also causes stress concentration due to the presence of notches, which causes a decrease in strength. In general, when such a notch is present, the strength is reduced as compared with a case where the shape change is continuous and smooth as in the case where there is a fillet.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a high-quality and low-cost manufacturing method of a vacuum vessel that solves the three main problems described above.

  In order to solve the above-described problems, a vacuum container manufacturing method according to the present invention is a vacuum container manufacturing method including a pair of side plates having stepped portions at upper and lower ends, and upper and lower plates fitted to the stepped portions. In the method, a molten material is disposed inside a recess provided in a horizontal joint surface between the side plate and the upper and lower plates, and a vertical groove surface formed on the joint surface between the side plate and the upper and lower plates is joined by welding, and A fillet portion is formed on the horizontal joint surface.

  According to the present invention, by joining the upper and lower plates and the side plates with the stepped portion, a low-cost vacuum vessel such as a waveguide having a low distortion and a high shape accuracy can be manufactured only by fusion bonding from the outside. Can do.

(A) is a figure which shows the manufacturing method which concerns on 1st Embodiment, (b) is an enlarged view of a welding part. The figure which shows the modification of the manufacturing method which concerns on 1st Embodiment. The figure which shows the manufacturing method which concerns on 2nd Embodiment. The figure which shows the modification of the manufacturing method which concerns on 2nd Embodiment. The figure which shows the manufacturing method which concerns on 3rd Embodiment. The figure which shows the manufacturing method which concerns on 4th Embodiment. (A), (b) is a figure which shows the manufacturing method which concerns on 5th Embodiment. The figure which shows the manufacturing method which concerns on 6th Embodiment. The figure which shows the conventional manufacturing method. It is a figure which shows the conventional manufacturing method, and is a figure which shows the example which sputter | spatter adhered to the container inner surface. It is a figure which shows the conventional manufacturing method, and is a figure which shows the example in which the opening part was formed in the container inner surface. It is a figure which shows the conventional manufacturing method, and is a figure which shows the example which distortion generate | occur | produced in the container. It is a figure which shows the conventional manufacturing method, and is a figure which shows the example which carried out the seal welding of the container inner surface.

  Hereinafter, an embodiment of a manufacturing method of a vacuum container according to the present invention will be described with reference to the drawings. In the following embodiments, a method of manufacturing a waveguide as a vacuum vessel will be described, but it is needless to say that the method can be applied to a general vacuum vessel.

(First embodiment)
A method of manufacturing a waveguide according to the first embodiment will be described with reference to FIG.
As shown in FIGS. 1A and 1B, the waveguide according to the first embodiment includes an upper and lower plate 1 and a pair of side plates 2, and a step portion having a predetermined width on the inner upper and lower sides of the pair of side plates 2. And the upper and lower plates 1 are configured to be fitted into the stepped portion. Thereby, a groove surface is formed in the vertical part (vertical groove surface a) and the horizontal part (horizontal groove surface b) of a joint surface.

  As a specific example, the thickness of the upper and lower plates 1 and the side plates 2 is about 10 mm, and the base material is made of oxygen-free copper CLASS 1 or the like and has high conductivity and low gas generation. The distance from the inner surface of the waveguide to the inner surface of the waveguide was about 3 mm. This structure was used for fusion bonding or soldering / brazing. 3 is a melting part.

  In addition, the joining was performed so as to include a part of the vertical groove surface a and the horizontal groove surface b from both end surfaces of the upper and lower plates 1, respectively. Thereby, since it joins so that both the vertical groove surface a and the horizontal groove surface b may be included, while being able to suppress the whole deformation | transformation, the waveguide of a firm structure can be obtained. The same effect can be obtained by joining only the portion of the horizontal groove surface a.

  As a result, the conventional example shown in FIGS. 10 to 13 does not have a function of suppressing deformation with respect to the stress at the time of joining and has a shape that is easily distorted, or spatter, opening portions, etc. are generated. In the embodiment, since the side plate 2 can receive a part of the stress at the time of joining, the entire deformation can be suppressed.

  Further, the upper and lower plates 1 have a structure in which the side plate 2 suppresses deformation at the time of welding, and it is easy to maintain a right-angle shape particularly at the inner side corners, so that opening and distortion of the corners can be prevented. At the same time, it is possible to prevent spatter from adhering to the inner surface of the container.

  Moreover, in the modification of 1st Embodiment, as shown in FIG. 2, the uneven | corrugated | grooved part 4 is provided in the junction part of the upper-and-lower board 1 and the side board 2. As shown in FIG. As a result, the corners on the inner surface side can be more firmly adhered to each other to prevent the mouth from opening, and the rectangular shape of the waveguide can be easily maintained.

  As described above, according to the first embodiment, the joint surfaces of the upper and lower plates and the side plates are welded and joined as a fitting structure using stepped portions, so that the overall surface is compared with the conventional one. A waveguide having a small distortion and capable of maintaining the shape of the inner side corner portion can be manufactured.

(Second Embodiment)
A method of manufacturing a waveguide according to the second embodiment will be described with reference to FIGS.
In the second embodiment, as shown in FIG. 3, by forming inclined stepped portions at the upper and lower end portions of the pair of side plates 2, and by forming inclined stepped portions at the left and right end portions of the upper and lower plates 1, The joining surface of the upper and lower plates 1 and the pair of side plates 2 has an inclined step structure. The groove surface is formed in an inclined portion (inclined groove surface c) and a vertical portion (vertical groove surface a).

  As a result, it is possible to suppress distortion at the time of joining and to apply stress in a direction in which the inner side corners are more closely adhered. In addition, since the corners on the inner surface side firmly adhere to each other, it is possible to prevent opening of the mouth and to make it easy to maintain the rectangular shape of the tube.

As a modification of the second embodiment, as shown in FIG. 4, welding is performed by combining welding of the inclined groove surface c and welding including the vertical groove surface a that crosses the inclined groove surface c. It is possible to further suppress the distortion at the time of joining, and to apply stress in a direction in which the inner side corners are more closely attached.
As a result, the corners on the inner surface side can be firmly adhered to each other to prevent the mouth from opening, and the rectangular shape of the waveguide can be easily maintained.

(Third embodiment)
A method of manufacturing a waveguide according to the third embodiment will be described with reference to FIG.
In the third embodiment, as shown in FIG. 5, the groove portion 5 is provided in the vicinity of both ends of the melting portion 3, and a portion weak in strength is intentionally formed, so that distortion is absorbed at that portion at the time of welding joining. Prevent distortion.
Thereby, it can be set as the structure which is easy to maintain the rectangular shape of a waveguide.

(Fourth embodiment)
A method of manufacturing a waveguide according to the fourth embodiment will be described with reference to FIG.
In the fourth embodiment, as shown in FIG. 6, a recess 6 is provided on the joint surface between the side plate 2 and the upper and lower plates 1, and the inner surface joint portion between the upper and lower plates 1 and the side plate 2 can be more firmly adhered to each other at the time of joining. And
As a result, the rectangular shape of the waveguide can be easily maintained, and the opening of the inner side corner can be prevented.

(Fifth embodiment)
A method for manufacturing a waveguide according to the fifth embodiment will be described with reference to FIGS.
In the fifth embodiment, as shown in FIGS. 7A and 7B, a recess 7 is provided on either the side plate 2 or the upper and lower plates 1 on the joint surface between the side plate 2 and the upper and lower plates 1. After the molten material 8 made of a solder material, a brazing material, or the like is disposed in the portion, the waveguide is assembled and welded.

  Due to the heat input during welding at this time, the molten material 8 disposed in the recess 7 is melted, and the gaps in the joint surface are filled as shown in FIG. At that time, the fillet portion 9 can be formed by selecting the molten material 8 and adjusting the joining conditions.

  As a result, the inner surface side of the container is securely sealed, and, for example, the inner surface side seal welding required for a vacuum container or the like is unnecessary, which can greatly reduce the cost and eliminate the work on the inner surface side. It is possible to avoid the quality risk of damaging the side.

  Further, since there is no air pool due to the absence of the gaps in the joint surfaces, there are effects of shortening the time for evacuation and preventing impurities from being mixed into the waveguide. Moreover, the risk that the intensity | strength of a joint surface falls by forming the fillet part 9 can be avoided.

  In general, such a joining method is conventionally performed in separate steps, but according to the fifth embodiment, welding of the vertical groove surface a and the horizontal groove surface b and sealing of the joint surface are performed. Since the process is performed simultaneously, the process can be shortened and the cost can be reduced. In addition, the lead time can be shortened.

  For example, in the conventional method, if the internal vacuum brazing is performed before and after welding, the time required for evacuation, temperature rise, brazing, cooling, and vacuum heating furnace is long. In particular, the larger the object is, the longer the restraint time becomes, and a separate vacuum heating furnace in which a large object enters is necessary. However, according to the fifth embodiment, these problems can be avoided.

(Sixth embodiment)
A method of manufacturing a waveguide according to the sixth embodiment will be described with reference to FIG.
In the sixth embodiment, as shown in FIG. 8, the cooling structure 10 such as a cooling pipe is disposed in the groove portion 11 near both ends of the melting portion 3, and the solder material, the brazing material, etc. are melted in the groove portion. A material (not shown) is arranged.
Thereby, the cooling structure 10 can be fixed in the groove 11 by utilizing heat input when welding the waveguide. The cooling structure 10 is installed to cool the waveguide.

  As mentioned above, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, combinations, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1 ... Up-and-down board, 2 ... Side plate, 3 ... Melting part, 4 ... Uneven part, 5 ... Groove part, 6 ... Recessed part, 7 ... Recessed part, 8 ... Molten material, 9 ... Fillet part, 10 ... Cooling structure, 11 ... Groove part , 15: Spatter, 16: Opening part

Claims (2)

In a manufacturing method of a vacuum vessel comprising a pair of side plates in which step portions are formed at upper and lower ends, and upper and lower plates fitted to the step portions,
A molten material is disposed inside a recess provided in a horizontal joint surface between the side plate and the upper and lower plates, and a vertical groove surface formed on the joint surface between the side plate and the upper and lower plates is joined by welding, and the horizontal joint surface A method of manufacturing a vacuum vessel, wherein a fillet portion is formed in the vacuum vessel. 2. The method of manufacturing a vacuum vessel according to claim 1, wherein the vertical groove surface and the horizontal groove surface formed on the bonding surface are bonded by welding.

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