JPS5924312B2 - double piping - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a double piping system consisting of an inner pipe through which a high-temperature fluid flows, for example, and an outer pipe through which a low-temperature fluid flows through a gap between the inner pipe and the inner pipe. This invention relates to the structure of a spacer that holds both inner and outer tubes at a predetermined distance.

FIGS. 1 and 2 are cross-sectional views showing the structure of conventional double piping.

The double piping is composed of an outer pipe 1, an inner pipe 2, and a plurality of plate-shaped spacers 3 arranged at appropriate intervals in the circumferential direction and the axial direction to maintain an appropriate distance between these two pipes. Each plate-shaped spacer 3 has a base portion fixed to the outer surface of the inner tube 2 by welding, and a radial tip portion thereof is arranged so as to be in contact with the inner surface of the outer tube 1.

However, in such a configuration, the inner diameter of the outer tube 1 and the inner diameter of the inner tube 2 are
Since there are manufacturing tolerances in the outer diameters of the outer tubes, a gap is created between the tip of the spacer 3 and the inner surface of the outer tube 1.

Therefore, during an earthquake, the inner tube 2 vibrates, and violent collisions occur repeatedly in the gap between the spacer 3 and the outer tube 1.
Not only does the outer tube 1 have the disadvantage of being subjected to impact loads, but when manufacturing this double tube, when fitting the inner tube to which the plate-shaped spacer is welded and fixed into the outer tube, the inner surface of the outer tube and the tip of the spacer are damaged. Another drawback was that the frictional resistance was large, making the fitting process difficult.

SUMMARY OF THE INVENTION An object of the present invention is to provide a double piping system that eliminates the drawbacks of the prior art described above, eliminates the gap between the spacer and the outer pipe, and reduces the impact load that occurs during earthquakes. .

In order to achieve this object, the present invention comprises a spacer including a spacer body made of a rigid rotating body and an elastic body made of a spring, and the spacer body made of the rotating body is moved by the spring to the inner surface of the outer tube. It is characterized by being supported in a rotatable and resilient manner.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 3 shows a first embodiment of the invention.

In the case of this embodiment, the spacer interposed between the outer tube 1 and the inner tube 2 consists of a sphere 4 constituting a spacer body and a spring 5 that brings the sphere 4 into elastic contact with the inner surface of the outer tube 1.

The spheres 4 are welded and fixed to the outer surface of the inner tube 2 at intervals approximately equal to the diameter of the spheres in both the axial and circumferential directions, and the tips are bent inward to prevent the spheres from flying out. It is surrounded and held by a guide 6.

In the figure, reference numeral 7 indicates a spring stand interposed between the spring 5, the sphere 4, and the inner tube 2, respectively.

According to this embodiment, the sphere 4 is pressed outward (upward in the figure) via the spring base I by the elastic force of the spring 5, and the outer tube 1
adheres to the inner surface of the

Therefore, the outer tube 1 and the inner tube 2 maintain an appropriate distance equal to the length corresponding to the diameter of the sphere 4 plus the length of the spring.On the other hand, in the event of an earthquake, etc. Coupled with the fact that the spacer body is in close contact with the inner surface of the outer tube, the spring acts as a shock absorber, eliminating the possibility of impact force acting on the outer tube as in the conventional case.

In addition, since the sphere 4 is a rigid body and also acts as a stopper, the distance between the outer tube 1 and the inner tube 2 will never become smaller than the diameter of the sphere 4 even if a very large shake occurs, and will always remain constant. A value greater than or equal to the value is guaranteed.

On the other hand, when manufacturing a double tube, when fitting the inner tube with the spacer attached to the outer tube, it is held by the guide 6 welded to the outer surface of the inner tube 2, and the bent part of the tip of the guide is held outward by the spring 5. The sphere 4, which is prevented from jumping out,
First, the spring 5 hits the inner surface of the outer tube 1 and is forced against it.
It is fitted into the outer tube in a state where it is pushed inward against the force, and thereafter it enters in the axial direction while rolling on the inner surface of the outer tube, making it easy to fit the outer tube.

At this time, even when it is necessary to adjust the circumferential position of the inner tube with respect to the outer tube, since the sphere 4 freely rolls in any direction, it is possible to adjust the circumferential position of the inner tube by rotating the inner tube in the circumferential direction. Another advantage is that it can be easily operated.

4 and 5 show a second embodiment of the invention.

In the case of this embodiment, compared to the case of the first embodiment, the spacer body has a predetermined thickness for strength and is positioned (orientated) so that it can roll on the inner surface of the outer tube 1 in the axial direction of the tube. The difference is that it is constituted by a disk 8 arranged at.

With this configuration, even if the thickness of the disk 8 is reduced within the allowable range for strength, it is possible to achieve almost the same effect as the spacer as in the case of the sphere of the first embodiment.
The cost of materials is reduced accordingly, and the weight of the device can be reduced.

As explained above, the present invention is configured such that the spacer body is elastically mounted on the inner surface of the outer tube using an elastic body, so that the distance between the inner and outer tubes can always be maintained at an appropriate value above a certain value. Not only that, during use, the gap between the outer tube and the spacer, which was a problem with the conventional technology, is eliminated, and the elastic and buffering effects of the elastic body act on the outer tube through the spacer in the event of an earthquake. Impact force can be reduced.

Furthermore, since the spacer is rotatable, fitting the outer tube into the inner tube is easy.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view taken perpendicular to the axial direction of a conventional double pipe, Fig. 2 is a cross-sectional view taken along line A-A in Fig. 1, and Fig. 3 is a cross-sectional view of a conventional double pipe according to the first embodiment of the present invention. FIG. 4 is an enlarged cross-sectional view of the main part cut along the axial direction of the spacer part of the double pipe according to the second embodiment of the present invention, and is a cross-sectional view taken in a direction perpendicular to the axial direction of the spacer part of the double pipe according to the second embodiment of the present invention. FIG. 5 is an enlarged cross-sectional view of the main part taken along line BB in FIG. 4. 1... Outer pipe, 2... Inner pipe, 4...
... Sphere, 5 ... Spring, 6 ... Guide, 8 ... Disk.

Claims (1)

[Scope of Claims] 1. In a double piping in which an inner pipe and an outer pipe are arranged to maintain a predetermined distance via a spacer, the spacer is a spacer body made of a rigid rotating body and an elastic body made of a spring. 1. A double pipe, characterized in that the spacer main body, which is made of the rotating body, is supported by the spring so as to be rotatably in elastic contact with the inner surface of the outer tube. 2. According to claim 1, the rotating body constituting the spacer body is constituted by a sphere held so as to be movable only in the radial direction by a guide fixed to the inner tube. Heavy piping. 3. In claim 1, the rotating body constituting the spacer body is held by a guide fixed to the inner tube so as to be movable only in the radial direction, and is positioned so as to roll in the tube axis direction. Double piping characterized by being composed of plates.