JPH0724541A - Shape memory alloy joint and its production - Google Patents

Abstract

PURPOSE:To eliminate welding for joining a wall and tube and to execute joining in short time and easily by arranging joining parts consisting of a joining part subjected to shape memorizing treatment to be deformed in the diameter shrinking direction and a joining part shape-memorized to be deformed in the diameter expanding direction at thermoelastic transforming. CONSTITUTION:A shape memory alloy joint 1 is so that a joining part at its one side is formed to a part 1a, which is subjected to a shape memorizing treatment so as to be deformed in the diameter shrinking direction (d) at thermoelastic transforming, also, a joining part at the other end is formed to a part 1b, which is shape-memorized so as to be deformed in the diameter expanding direction (f) at thermoelastic transforming. The part 1b to expand tube of the joint 1 is inserted into the tube hole arranged in a tube plate 40, a tube 41 is inserted in the part 1a to shrink tube. At this condition, the joint part is heated, the part 1b of tube plate side is expanded, the part 1a of tube side is shrunk, both are joined in tight adhesion.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shape memory alloy joint and a method for manufacturing the same, and more particularly to a shape memory alloy joint used for connecting pipes, rods or wires, and a method for manufacturing the same. is there.

[0002]

2. Description of the Related Art Joints made of shape memory alloys which have been generally adopted conventionally are made of Ni-Ti alloys or Cu alloys,
Shape memory processing is usually performed so as to deform in the diameter reducing direction during thermoelastic transformation.

When used as a pipe joint, for example, the end portion of the pipe to be connected is inserted into the joint connection port, heat is applied to the joint portion, and the joint portion is thermally shrunk, I try to make a close connection with.

Generally, this gives a sufficiently tight bond,
To improve the adhesion and airtightness, the inner wall surface of this joint may be undulated, a liner may be inserted between this inner wall surface and the pipe, or the inner wall surface of the joint may be thermoset. Coating and baking of mold resin is also performed.

In general, this type of shape memory alloy joint is very effective for joining pipe materials, that is, rod-shaped joints, in terms of adhesion and shortening of joining work time. It is often used to combine rod-shaped bodies.

Therefore, in the case of joining a pipe to a wall of a fluid container other than the pipe materials, first, a short-length pipe is welded to the wall of the container and the pipe to be connected is connected to the shape memory alloy. The connection is made with a joint made by the manufacturer.

Incidentally, Japanese Patent Application Laid-Open No. 3-51597 can be cited as one related to this type of shape memory alloy joint.

[0008]

As described above, this shape memory alloy joint is very effective in terms of workability for joining together pipe materials, but it cannot be used for pipes on walls such as container walls. When joining, it is necessary to perform welding work, for example, in the work inside the reactor, a lot of time is spent on this welding work, and it becomes a long time work in a bad environment, There was a dislike that the original goodness of the shape memory alloy joint was not exhibited.

The present invention has been made in view of the above, and an object thereof is to connect a wall and a pipe even if the connecting work does not involve welding work and the connecting work can be performed in a short time. And to provide this type of shape memory alloy joint which can be easily performed.

[0010]

That is, the present invention provides a shape memory alloy joint in which one side joint portion is a shape memory treated portion so as to be deformed in a diameter reducing direction during thermoelastic transformation, and the other side. The side-coupling portion is a portion subjected to shape memory processing so as to be deformed in the radial direction during thermoelastic transformation so as to achieve the intended purpose.

[0011]

Operation: That is, in the shape memory alloy joint formed in this way, the end on the side that is deformed in the radial expansion direction during thermoelastic transformation is inserted into the hole provided in the container wall, and heat is applied. By performing the expansion treatment, it is possible to easily connect the pipes, and in particular, welding work is not required, and the pipes can be easily connected to the container wall in a short time.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the illustrated embodiments. FIG. 2 shows a cross section of the shape memory alloy joint of the present invention.

The shape memory alloy joint 1 has a portion subjected to shape memory treatment so that one side joint portion (right side in the figure now) of the joint 1 is deformed in the diameter reduction direction d during thermoelastic transformation (joining assembly). 1a, and the other side coupling part (left side in the figure)
Is formed in the portion 1b that has undergone shape memory processing so as to be deformed in the radial expansion direction f during thermoelastic transformation.

Reference numeral 2 in the drawing denotes a filler layer applied to the joint surface of the joint. A liquid resin is generally used as the filler.

In order to manufacture such a joint, as shown in FIG. 3 showing the original material, the portion 1a which is processed so as to be deformed in the diameter reducing direction is the original joint material (joint material) 1A.
Has a small diameter in advance and is subjected to a pipe expanding process as indicated by an arrow g in the figure at the time of shape processing.

On the other hand, the portion 1b which is processed so as to be deformed in the radial direction is subjected to the reverse processing. That is, the diameter of the original shape of the joint is formed large in advance, and at the time of the shape processing, a contraction processing is performed as shown by an arrow h in the drawing.

The shape memory alloy joint thus formed is a joint in which the left side (1b) in the figure is deformed in the tube expanding direction and the right side (1a) is deformed in the tube contracting direction by thermoelastic transformation.

Contrary to this, on the other hand, first, a straight pipe type original joint is manufactured, and the portion to be deformed in the radial expansion direction by the thermoelastic transformation is subjected to a diameter reduction treatment, and the thermoelastic transformation is performed in the diameter reduction direction. The joint can also be obtained by expanding the diameter of the portion to be deformed.

FIGS. 4 and 5 show an example in which the original shape 1A of the shape memory alloy joint is subjected to the pipe expanding and contracting treatments, and 6 is the original shape 1A of the shape memory alloy joint. The jig 7 is a rod-shaped jig for performing the contraction, and 7 is a jig for performing a contraction process, which is formed in a half-ring body.

In the tube expanding process, a jig 6 for performing the tube expanding process is inserted into the original shape 1A of the memory alloy joint, and the tube expanding process is carried out for the portion which is contracted during the thermoelastic transformation.

Next, in the contracting process, a jig for contracting the original shape memory alloy joint 1A is inserted with a jig 6 for expanding the shape memory alloy joint being inserted. Push to 7. Accordingly, the original shape 1A of the shape memory alloy joint becomes the shape memory alloy joint 1 that is deformed in two directions, the expansion direction and the contraction direction, during the thermoelastic transformation.

FIG. 1 shows an example in which the memory alloy joint thus formed is used in a heat exchange device of a nuclear facility.

In the figure, 40 is a tube plate of the heat exchange device, and a tube 41 is connected to this tube plate.
It is performed by the shape memory alloy joint 1.

That is, the tube hole 4 provided in the tube sheet 40.
0a is inserted into one side of the shape memory alloy joint 1, that is, the side 1b that expands during thermoelastic transformation, and the other side of the shape memory alloy joint 1, that is, the side that contracts during thermoelastic transformation, heat exchange The tube 41 for insertion is inserted.

In this state, when heat is applied to the shape memory alloy joint portion, the portion of the shape memory alloy joint on the tube sheet side expands and the portion on the tube side contracts to tightly bond the two. .

At this time, the portion which is connected to the tube plate 40 of the heat exchanger and which deforms in the tube expanding direction during the thermoelastic transformation is set to be longer than the wall thickness of the tube plate 40 of the heat exchanger. That is, if the joint is formed so as to protrude (d) from the surface of the tube sheet 40,
Since the protruding portion does not exert a restraining force inside and outside the tube plate of the heat exchanger when deformed in the tube expanding direction during the thermoelastic transformation, the shape memory alloy joint 1 and the tube plate 40 of the heat exchanger are separated from each other. Expand the pipe larger than the connecting part.

As a result, the shape memory alloy joint 1 is
The tube plate 40 of the heat exchanger is caulked, and a strong connection that does not come out inside is possible. In addition, the heat generated by the curing reaction of the filler 2 causes the shape memory alloy joint 1
Is subjected to a thermoelastic transformation, and the main agent and the curing agent undergo a curing reaction to fill a minute gap with the tube sheet 40 of the heat exchanger.

At the same time, since the filler also exerts the effect of adhering, it is possible to make a connection that has high strength and high airtightness, and can prevent crevice corrosion caused by the potential difference due to the contact of dissimilar metals.

In the explanation of the abnormality, the connection between the tube sheet and the pipe has been explained, but it is possible to connect the pipes with each other by using this joint, and it is adopted not only as a two-way joint but also as a three-way joint. It will be possible.

FIG. 6 shows an example in which pipes are combined. That is, in the example in which the pipe 41 is joined to the mother pipe 41b, a hole H is provided in the connecting portion of the mother pipe 41b, and the side 1 that expands at the time of thermoelastic transformation of the shape memory alloy joint 1
Insert b.

Further, FIG. 7 shows an example in which the pipes are connected by a straight pipe. In this case, in the shape memory alloy joint 1, the side 1a that expands during the thermoelastic transformation is inserted inside the tube 42a, and the side 1b that contracts during the thermoelastic transformation forms the tube 4a.
It is applied so as to be outside of 2b.

Further, FIGS. 8 and 9 show an example in which it is adopted as a reactor pressure vessel in a boiling water nuclear power plant.

FIG. 8 is a diagram showing a schematic structure of the reactor containment vessel 49 and the reactor pressure vessel 50. At the bottom of the reactor pressure vessel 50, as indicated by the circle Q in the figure, I
There is a penetrating portion of the pipe 51 called a CM housing.

FIG. 9 is an enlarged and cross-sectional view of this portion, which will be described below with reference to this drawing. The shape memory alloy joint 1 is manufactured from a shape memory alloy of a type that undergoes thermoelastic transformation by heat treatment, and an example in which a two-component resin is used as the filler 2 will be described.

In the figure, 50 is a reactor pressure vessel lower mirror, and 51 is I.
A CM housing, 52 is a spacer, and 1 is a shape memory alloy joint.

In this case, the shape of the shape memory alloy joint 1 is somewhat different from that described above because it is a connection between the wall and a pipe penetrating the wall. That is, in order to manufacture the shape memory alloy joint in this case, as shown in FIG. 10, the portion 1a processed to be deformed in the diameter reducing direction on both end sides has a diameter of the original joint 1A. , Which has been formed small in advance, is subjected to a pipe expanding process as indicated by an arrow g in the drawing at the time of shape processing.

On the other hand, the central portion 1b which is processed so as to be deformed in the radial direction is subjected to the opposite processing. That is, the diameter of the original shape of the joint is formed large in advance, and at the time of the shape processing, a contraction processing is performed as shown by an arrow h in the drawing.

The shape memory alloy joint thus formed is a joint in which the central portion 1b is deformed in the tube expanding direction and both end sides 1a are deformed in the tube contracting direction by thermoelastic transformation.

Then, the central portion of the alloy joint 1 which is deformed in the expanding direction during the thermoelastic transformation is connected to the reactor pressure vessel lower mirror 50, and the ICM housing 51 is connected to both ends of the alloy joint 1 where it is deformed in the contracting direction during the thermoelastic transformation. Connect with.

At this time, the reactor pressure vessel lower mirror 50 is processed into a conical shape so that the inside of the reactor becomes larger, and the spacer 52 is used to connect the shape memory alloy joint 1 and the reactor pressure vessel lower mirror 50. Connecting.

In this case, as described above, the portion which deforms in the tube expanding direction during the thermoelastic transformation is set to be longer than the spacer 52 so that the spacer 52 does not fit when deformed in the tube expanding direction during the thermoelastic transformation. Since the restraining force does not work in the portion, the pipe is expanded larger than the joint portion between the shape memory alloy joint 1 and the spacer 52. As a result, the shape memory alloy joint 1 is effective because the spacer 52 is caulked.

Since the pressure inside the reactor is high, a force acts in a direction to push the shape memory alloy joint 1 and the spacer 52 out of the reactor. However, the reactor pressure vessel lower mirror 50 is processed into a cone shape having a larger inside of the reactor, and the spacer 52 is used to form the shape memory alloy joint 1 and the reactor pressure vessel lower mirror 50.
With the structure in which the joint between the shape memory alloy joint 1 and the spacer 52 is pushed to the outside of the reactor, the joint force between the reactor pressure vessel lower mirror 50 and the spacer 52 is increased. Strengthen.

As described above, according to the joint of the present invention, it is not necessary to weld the wall and the pipe, and therefore the work in the reactor facility can be shortened.

[0044]

As described above, according to the present invention, the shape memory alloy joint is subjected to shape memory treatment so that the one side connecting portion is deformed in the diameter reducing direction during thermoelastic transformation, and the other side connecting portion. Since it is formed so as to be shape-memory processed so as to be deformed in the radial expansion direction during thermoelastic transformation, the shape memory processing is performed in the wall hole of the pipe connection portion so as to be deformed in the radial expansion direction during the thermoelastic transformation. It is possible to connect the pipe to the wall simply by inserting the section and expanding the diameter.Therefore, even when connecting the wall and the pipe, there is no welding work in the connection work, and the connection work can be done in a short time. And it can be done easily.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing an embodiment using a shape memory alloy joint of the present invention.

FIG. 2 is a vertical sectional side view showing an embodiment of the shape memory alloy joint of the present invention.

FIG. 3 is a vertical cross-sectional side view showing an example of an original material for a shape memory alloy joint of the present invention.

FIG. 4 is a vertical cross-sectional side view showing a processing state of an original material of the shape memory alloy joint of the present invention.

FIG. 5 is a vertical cross-sectional side view showing a processing state of an original material of the shape memory alloy joint of the present invention.

FIG. 6 is a vertical sectional side view showing another embodiment using the shape memory alloy joint of the present invention.

FIG. 7 is a vertical sectional side view showing another embodiment using the shape memory alloy joint of the present invention.

FIG. 8 is a schematic view of a boiling water nuclear power generation facility in which the shape memory alloy joint of the present invention is used.

FIG. 9 is a vertical sectional side view showing another embodiment using the shape memory alloy joint of the present invention.

FIG. 10 is a vertical cross-sectional side view showing a processing state of the original material of the shape memory alloy joint of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Shape memory alloy joint, 1a ... the part processed so that it may deform | transform in a diameter reduction direction, 1b ... the part processed so that it may expand / contract in a diameter direction, 2 ... filler.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takahiko Kato 3-1-1, Saiwaicho, Hitachi, Ibaraki Hitachi Ltd. Hitachi factory (72) Inventor Masato Koshiishi 3-chome, Saiwaicho, Hitachi, Ibaraki No. 1 No. 1 Stock Company Hitachi Ltd. Hitachi factory

Claims (8)

[Claims] 1. A connecting portion that is shape-memory processed so as to be deformed in a diameter-reducing direction during thermoelastic transformation, and a connecting portion that is shape-memory processed so as to be deformed in a diameter-expanding direction during thermoelastic transformation. A shape memory alloy joint characterized by the above. 2. One of the coupling ends is subjected to shape memory processing so as to be deformed in a radial direction during thermoelastic transformation, and the other coupling end is subjected to shape memory processing so as to be deformed in a radial direction during thermoelastic transformation. Shape memory alloy joint characterized by 3. A first bonding portion that has undergone shape memory processing so as to deform in the diameter-reducing direction during thermoelastic transformation, and a second bonding portion that has undergone shape memory processing so as to deform in the diameter-expanding direction during thermoelastic transformation. A shape memory alloy joint, wherein a filler layer is provided on each of the inner wall surface of the first joint portion and the outer wall surface of the second joint portion. 4. The shape memory alloy joint according to claim 3, wherein a spiral groove is provided on a part or the whole of the inner wall surface of the first joint portion and the outer wall surface of the second joint portion. . 5. One of the coupling ends is subjected to shape memory processing so as to be deformed in a radial contraction direction during thermoelastic transformation, and the other coupling end is subjected to shape memory processing so as to be deformed in a radial expansion direction during thermoelastic transformation. At the same time, the coupling end that deforms in the diameter-reducing direction during the thermoelastic transformation is coupled to the pipe, and the coupling end that deforms in the diameter-expanding direction during the thermoelastic transformation is coupled to the hole in the container wall. Shape memory alloy joint. 6. One end is insert-coupled into a hole in the wall of the container,
And, in the joint having the other end coupled to the pipe, the joint end coupled to the wall is formed so as to be deformed in the radial expansion direction during thermoelastic transformation, and the joint end coupled to the pipe is A shape memory alloy joint characterized by being formed so as to be deformed in a diameter reducing direction during thermoelastic transformation. 7. The shape memory alloy joint according to claim 5, wherein the tip of the joint portion that deforms in the radial expansion direction during the thermoelastic transformation is formed so as to protrude from the container wall. 8. A first bonding portion that has undergone shape memory processing so as to deform in a diameter reducing direction during thermoelastic transformation, and a second bonding portion that has undergone shape memory processing so as to deform in a diameter expanding direction during thermoelastic transformation. In a method for manufacturing a shape memory alloy joint including a portion, a rod-shaped jig for performing a pipe expanding process is inserted inside the shape memory alloy joint material on the side to be the first joint portion, and the pipe expanding operation is performed. Step, in a state where the rod-shaped jig is inserted, a step of inserting the side to be the second coupling portion into a jig for performing a tube-reducing process and performing a tube-reducing operation. A method for manufacturing a shape memory alloy joint, which comprises a step of removing a jig.