JPS61115307A - Thermal radiation shield plate for superconducting magnet - Google Patents

Abstract

PURPOSE:To keep uniform a shielding effect as a whole by a structure wherein shield plates on inner-tube and outer-tube sides are fixed to the inner and outer tubes of a cryostat respectively at a plurality of points in the axial and circumferential directions and the thermal shrinkage in the circumferential direction is absorbed by a change in the shape of the shield plates between supporting points. CONSTITUTION:Radiation shield plates 6a and 6b are provided between a coil and a cryostat in order to shield a radiant heat so that a heat from the outer tube 5a of the cryostat, which is an atmospheric temperature, and a heat from the inner tube side 5b may not be transmitted to a superconducting coil 1, and liquid nitrogen pipings are wound round thereon respectively so as to keep them at the temperature of liquid nitrogen. Moreover, a heat insulating material 7 is provided on the cryostat side, and it is supported by the cryostat. The shield plates are fixed by bolts 9 to the cryostat through the intermediary of distant pieces 8 fixed to the cryostat in all the four places in the circumferential direction at supporting points in the center in the axial direction. At other supporting points fixing bolts 10 and the distant pieces 8 are fixed with a gap between them, and therefore the move of the shield plates in the axial direction is made free.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a superconducting magnet, and particularly to a thermal radiation shield plate for a solenoid-type superconducting electromagnet used in the field of high-energy materials.

[Background of the invention]

Conventionally, the radiation shield plate of a superconducting electromagnet has been divided into five parts and attached to the cryo to prevent thermal stress from occurring due to the temperature difference between the cryo and the cryo at atmospheric temperature, and the method has been used to absorb the difference in thermal shrinkage (Utility Model Publication No. 57-134809). For those with vertical lunoid shafts, there is a method of absorbing the lunoid by hanging it from the upper end (Special Publication No.
797 Kei6ru has large movement at the split and seam, and the insulation layer attached to the shield plate is easily damaged.If the hanging method is applied to a case where the laid shaft is horizontal, the entire shield plate becomes smaller due to heat shrinkage. The disadvantage is that the lower end rises by the amount of contraction, causing the center of the shield plate cylinder to shift.

[Purpose of the invention]

SUMMARY OF THE INVENTION The object of the present invention is to provide a 7-fold plate which compensates for the drawbacks of the prior art.

[Summary of the invention]

The gist of the present invention is to fix the inner and outer shield plates to the inner and outer cylinders of the cryo at multiple points in the axial and circumferential directions, and to provide support at these support points in the axial direction of the solenoid shaft. It is movable in the radial direction and fixed in the radial direction, and thermal contraction in the circumferential direction is absorbed by the deformation of the seven-fold plate between the supporting points. However, in order to clarify the reference of the position in the axial direction, all the support points of one section in the axial direction may be fixed in the axial direction.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 1 shows the structure of an indirectly cooled solenoid type superconducting electromagnet, and FIG. 2 shows its cross section.

1 is a superconducting coil in the form of a superconductor, which is supported by a support cylinder 2 around which a liquid helium cooling tube is wound, and is supported by an axial support 3 and a radial length bow 4.4' of a vacuum vessel (hereinafter referred to as cryo) and an outer cylinder 5aiC. be done.

The radiation shield plates 5a and 5b prevent the heat from the cryo outer cylinder 5a and the inner cylinder 5b, which are heated at atmospheric temperature, from reaching the superconducting coil 1.
In order to shield the radiant heat from being transmitted to the cryo, it is installed between the coil handle 2 and the cryo. A liquid nitrogen pipe is wound around the cryo to maintain the liquid nitrogen temperature, and a heat insulating material 7 is provided on the cryo side. Supported by Ri2io.

Both the outer cylinder side and the inner cylinder side are supported at five support points in the axial direction, and at four points in one cross section in the radial direction.

As shown in FIG. 3, the central support point in the axial direction is fixed to the cryo using bolts 9 at all four locations in the circumferential direction via distance pieces 8 fixed to the cryo.

At other supporting points, the fixing bolt 1 and the distance piece 8 are fixed with a gap as shown in FIG. 4, so that the shield plate can move freely in the axial direction. Figures 3 and 4
As you can see, it cannot move in the radial direction.

Further, as shown in FIG. 5, movement in the circumferential direction is also prevented.

〔Effect of the invention〕

According to the present invention, when the radiation shield plate is cooled and thermally contracted, the radiation shield plate is contracted in the axial direction toward the central fixed point, and in the radial direction, between the supporting points and the outer cylinder side, it is Although the shield plate deforms in the direction away from the cylinder and in the direction towards the cryo-inner cylinder on the inner cylinder side, the entire shield plate does not become eccentric with respect to the axial center of the cryo, and the overall shielding effect is uniform, and There is a gap in the split part like the split type,
It does not reduce shield effectiveness.

[Brief explanation of the drawing]

Fig. 1 is a side view of only the upper half of the solenoid type superconducting electromagnet according to the present invention in section, Fig. 2 is a cross-sectional view taken along the ■-■ arrow in Fig. 1, and Fig. 3 is a detailed view of the section ■ in Fig. 1. , Figure 4 is the first
5 is a sectional view taken along the line v--■ in FIG. 4. 1... superconducting coil, 2... support cylinder,
5... Vacuum container (RI2IO), 6... Radiation shield plate, 7... Insulating material.

Claims (1)

[Claims] 1. A solenoid-shaped superconducting coil, this superconducting coil is surrounded by a heat radiation shield plate, and its outer periphery is formed by cryo consisting of an inner and outer cylinder and an end plate, and the solenoid shaft is In the superconducting electromagnet whose surface is horizontal, the heat radiation shield plate is formed of cylinders on the inner cylinder side and the outer cylinder side separately, and has a structure in which each of the plates is supported at a plurality of points on the inner and outer cylinders of the cryo, and these support points 1. A thermal radiation shield plate for a superconducting magnet, characterized in that it is fixed in the radial direction and movably supported in the axial direction. 2. In claim 1, the supporting points are fixed in the axial direction - only the supporting points in the cross section are fixed in both the radial direction and the axial direction, and the others are fixed in the radial direction and movable in the axial direction. A thermal radiation shield plate for a superconducting magnet characterized by being supported by.