JPH02165600A - Manufacture of superconductive high frequency accelerating cavity - Google Patents

Abstract

PURPOSE:To simplify the forms of parts for easy processing and improve the utilizing efficiency of an electron beam welder and the quality of a product by setting disks on a jig at determined intervals, inserting the disks into a cylinder, and welding the cylinder and the disks by the radiation of electron beams from the outside of the cylinder. CONSTITUTION:To dispose disks (irises) 9 consisting of perforated superconductors in a cylinder 14 consisting of a superconductor at determined intervals, the disks 9 are set on a jig 12 at the determined intervals and then inserted into the cylinder 14, and electron beams are radiated from the outside of the cylinder 14 to weld the disks 9 to the cylinder 14. Hence, the processing of the parts easy with the simple forms of the parts such as the perforated discs 9 and the cylinder 14, the electron beam welding is also easily conducted, and thus the reliability can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a superconducting high frequency acceleration cavity using Nb or the like for a charged particle accelerator.

[Conventional technology]

The principle of an accelerator is to adjust the phase velocity of a traveling wave that has an electric field component in the direction in which the charged particles travel so that the charged particles are always in the acceleration phase and are affected by the accelerating electric field. This is to accelerate the In an accelerator that uses a high-frequency electric field, an acceleration cavity is used as a device to generate the high-frequency electric field.

In a superconducting acceleration cavity, a disk (iris) made of a superconductor with a hole is installed inside the cavity made of a superconductor in order to improve the accelerating electric field. That is, for example, the fifth
As shown in the figure, irises (2) made of Nb are installed at regular intervals on the Nb cylinder (+). This superconducting acceleration cavity is manufactured by the following method. That is, a) As shown in Fig. 3, a plurality of integrated iris (3) and cylindrical half cells (4) on both sides are made of Nb
It is carved from a block of metal such as
4) A method of welding and connecting the peripheral end portion (5) with an electron beam to form a cavity.

Alternatively, as shown in Fig. 4, a half cell (6) with one end squeezed is formed by pressing and squeezing from a metal plate made of Nb, and the half cell (6) is squeezed. There is a method of welding the peripheral end (7) and the other peripheral end (8) to each other using an electron beam to form a cavity.

Superconducting radio frequency acceleration cavities require very low surface resistance, so there should be no contact resistance.

Therefore, they must be reliably joined by electron beam welding or the like.

[Problem to be solved by the invention]

However, with conventional manufacturing methods, many processes are required for processing, and each time each part is welded, the vacuum of electron beam welding must be broken to create a cent amplifier for the part, and then the vacuum must be drawn again. However, there is a problem in that the wasted time of the work increases. In addition, in method (a), there is a problem in that a large amount of material is wasted because machining is performed.

The present invention has been made in view of the above points.
The purpose is to provide a method for manufacturing a superconducting high-frequency acceleration cavity that makes the parts simple in shape, facilitates processing, and improves the efficiency of use of an electron beam welding machine and the quality of the product.

[Means and actions to solve the problem]

In order to achieve the above object, the present invention provides a method for manufacturing a superconducting high-frequency acceleration cavity, in which disks (iris) made of a superconductor with holes are installed at desired intervals in a cylinder made of a superconductor. , the discs are set on a jig at desired intervals, then the discs are inserted into the cylinder, and then an electron beam is irradiated from the outside of the cylinder to separate the cylinder and the disc. Provided is a method for manufacturing a superconducting high frequency acceleration cavity, which comprises welding.

In the above manufacturing method, it is sufficient to form a cylinder and a disk with holes, and the forming process can be easily performed. In addition, in electron beam welding, a cylinder with a disc inserted is set in a vacuum, and while rotating the cylinder, an electron beam is irradiated from the outside of the cylinder to the part where the disc is installed. - After welding one disc, move the cylinder and weld another disc, and repeat this process one after another to weld multiple discs into the cylinder. . Therefore, with this manufacturing method, if the cylinder is set in a vacuum, all the disks can be welded without breaking the vacuum by simply rotating the cylinder and moving it in the axial direction, and electron beam welding. Improves workability and quality.

〔Example〕

The present invention will be described below based on embodiments shown in the drawings.

The manufacturing method according to this example is as follows. That is, b) In Figure 1(a), the thickness is 5cm and the inner diameter is 12m.

An iris (9) made of Nb with an outer diameter of 84w was fabricated, and then a support rod (12a) having 40 grooves of 116 mm (01) formed by two convex portions 0ω at a pitch of 35cm was fabricated.
, (12b) Insert two into the holes of 40 iris (9) to make the dotted line state, and place an iris (9) on each groove 01).
be installed.

C) Next, lift the support rod (12a) from the dotted line position to the solid line position, fit the iris (9) into the groove 00, lower the support rod (12b) from the dotted line position to the solid line position, and place the iris (9) into the groove 00. Insert the iris (9) into the.

2) Next, as shown in Figure 1(b), two support rods (
An insertion rod θ with an elliptical cross section is inserted between 12a) and (12b).
Insert the rod, with the long diameter of the insertion rod side facing vertically,
The support rods (12a) and (12b) are supported at intervals in the vertical direction, and the iris (9) is fixed in the groove (10, '<-
4,.

e) Next, as shown in FIG.
) is inserted into the Nb cylinder 04 with an inner diameter of 84 m.

Next, set the cylinder 04) into which the iris (9) has been inserted in a vacuum, and while rotating the cylinder 0411, attach the cylinder to the welder 0!9 on the outer periphery of the cylinder 041 where the iris (9) is located. The inner surface of the cylinder 04 and the peripheral end of the iris (9) are welded by irradiating a day focus electron beam with sufficient intensity to pass through the iris (9). After welding one iris (9),
By moving the cylinder to move the electron beam irradiation position to the adjacent iris (9) and repeating this process,
Weld 40 irises (9). In this way,
All the irises (9) can be welded by setting the welding device in a - degree vacuum, and the work time for electron beam welding can be shortened.

g) Next, after welding is completed, take out the cylinder (b) from the vacuum, rotate the insertion rod so that the longer diameter direction is horizontal, and pull it out.6 Next, remove the two support rods (12a)
), (12b), are moved to the dotted line position in Fig. 1(a),
Remove Iris (9) from medium heat.

As mentioned above, according to this example, the parts have a simple shape of a perforated disk and a cylinder, and are easy to process, and electron beam welding is also easy to perform, so the reliability is improved. .

〔Effect of the invention〕

As explained above, according to the present invention, a disk made of a superconductor with holes is set on a jig at desired intervals, and then the disk is inserted into a cylinder made of a superconductor. Since the cylinder and the disk are welded by irradiating an electron beam from the outside of the cylinder, there are excellent effects of improving welding efficiency and quality reliability.

[Brief explanation of the drawing]

FIG. 1(a) is an explanatory diagram of the assembly process of an embodiment according to the present invention, FIG. FIG. 3 is an explanatory diagram of one conventional example during welding, FIG. 4 is an explanatory diagram of another conventional example during welding, and FIG. 5 is a longitudinal cross-sectional view of a superconducting high-frequency cavity. 1.14...Cylinder, 2.3.9...Iris,
4.6...half cell, 5,7.8...peripheral end,
IO...Protrusion, 11...Groove, 12a, 12
b... Support rod, 13... Insert rod, 15...
·welded part. Patent Dekojin D Kawa 11ki Kogyo Co., Ltd. Figure 1 (a) Figure 1 (b) Figures 2 to 4

Claims (1)

[Claims] In a method for manufacturing a superconducting high frequency acceleration cavity, in which disks (iris) made of a superconductor with holes are installed at desired intervals in a cylinder made of a superconductor, the disks are placed on a jig at desired intervals. of the superconducting high frequency acceleration cavity, the disc is then inserted into the cylinder, and then an electron beam is irradiated from the outside of the cylinder to weld the cylinder and the disc. Production method.