JPH085501A - Burst test pipe material end plugging method - Google Patents

Abstract

(57) [Summary] [Purpose] In a method of plugging the end of a burst test pipe material, a machine that can easily and quickly withstand high test pressure without using special processing such as welding. Solidly plug. [Structure] A tapered ring body 1, a plug body 5 having a throttle hole 3 into which a small-diameter portion side of the ring body 1 is inserted, and the ring body 1 is screwed into the plug body 5 to constrict the ring body 1 into the throttle hole 3. Nut member 9
And a spacer pipe 10 fitted onto the pipe material P, the ring body 1 is fitted onto the spacer pipe 10 fitted to the end portion of the pipe material P such that the small-diameter portion side is the pipe end side. By inserting the small diameter side of the ring body 1 into the throttle hole 3 of the plug body 5 and tightening the nut member 9, the ring body 1 is installed in the throttle hole 3 and a pipe material is inserted via a spacer pipe. Narrow P.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a burst test for confirming the strength of a metal tube such as a control rod guide tube of a PWR fuel assembly, and more particularly to the end of pipe material used in this burst test. The present invention relates to a closed end method for closing in a closed state.

[0002]

2. Description of the Related Art A closed end burst test is one end of a pipe material which is sealed by end plug welding or rubber packing.
Water is poured from the opposite end and a constant water pressure is applied to rupture the tube. The rupture pressure at that time is measured and it is confirmed whether the standard is satisfied.

However, in the above-described end plug welding, the pipe cannot be plugged suddenly, and the process such as vacuuming of the welding takes time, which cannot be dealt with in an emergency.

In addition, the above-mentioned plug with the rubber packing has a problem that the test condition is limited because the plug does not have a predetermined pressure when the test pressure is high.

[0005]

DISCLOSURE OF THE INVENTION The present invention addresses the above-mentioned situation, and by finding a new method for plugging a pipe material, the end of the pipe material can be easily and quickly subjected to a high test pressure. The purpose is to firmly seal the container so that it can withstand.

[0006]

That is, the method of plugging the end portion of the pipe material for burst test according to the present invention, which is suitable for the above object, is as follows.
A tapered ring body into which a pipe material is inserted and a bottomed throttle hole into which a small diameter side of the ring body is inserted, and an outer surface having a male screw portion coaxial with the throttle hole. A nut member having a bag-shaped female thread portion that is screwed into the male thread portion of the stopper and having a hole portion into which the pipe material is inserted at the center of the bag-shaped portion; Using a spacer pipe that fits and is inserted into the ring body together with the pipe material,
While fitting the spacer pipe on the end of the pipe material,
The ring body is externally fitted to the spacer pipe so that the small diameter portion side is the pipe end side, and further, the small diameter portion side of the ring body is inserted into the throttle hole of the plug body and the nut member is fastened. Thus, the ring body is installed in the throttle hole to squeeze the spacer pipe, and the spacer pipe is pressed against the peripheral surface of the pipe material.

[0007]

According to the above method of the present invention, the end portion of the pipe material is mechanically simply and quickly mechanically sealed without using any means such as welding, and the pipe material is firmly sealed so as to be able to cope with a high test pressure. It is possible to

Even if it is difficult to cause the ring body to bite into the pipe material due to a large gap between the inner diameter of the ring body and the outer diameter of the pipe material, the wall thickness of the spacer pipe may be changed. It is possible to make the gap small by adjusting and allow the ring body to bite into the pipe material through the spacer pipe.

[0009]

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

FIG. 1 is a cross-sectional view showing an embodiment of a method for plugging an end portion of a pipe material according to an embodiment of the present invention, FIG. 2 is a cross-sectional view showing a state after the method is carried out, and FIG. 3 is various members used in the method. FIG.

That is, in the method of the above embodiment, as shown in each of the above figures, the pipe material P is fitted in the center and
A ring body 1 having a truncated cone shape with a tapered outer peripheral surface, a washer member 2 which is superposed by fitting the step portions 1a and 2a to the ring body 1, and a small diameter of the ring body 1. A plug body 5 having a bottomed tapered throttle hole 3 into which the part side is inserted and having an external thread portion 4 coaxial with the throttle hole 3 on the outer surface.
And a nut member having a bag-shaped female thread portion 6 to be screwed with the male thread portion 4 of the plug body 5 and having a hole portion 8 formed at the center of the bag portion 7 for inserting the pipe material P therein. 9 and a spacer pipe 10 which is fitted over the pipe member P with some play or with a gap for sliding and is inserted into the ring body 1 together with the pipe member P. The ring body 1 is usually made of metal such as stainless steel.

Hexagon nuts are integrally formed on the plug body 5 and the nut member 9, and the bag-shaped portion 7 of the nut member 9 is formed by fastening the plug body 5 and the nut member 9 to each other. The lower surface of the ring body 1 presses the ring body 1 toward the throttle hole 3 via the washer member 2. And this aperture 3
A part of the ring body 1 pushed in is narrowed by the throttle hole 3, and the spacer pipe 10 and the pipe material are radially narrowed.

Further, in this embodiment, a control rod guide tube having an outer diameter of about 10 to 15 mm and made of Zircaloy 4 is used as the pipe material P, and the spacer pipe 10 is made of the same metal as that of the pipe material P or Stronger metal than this, thinner than this, length 20-30mm
I used the one.

On the other hand, in the plugging method for the burst test pipe material P according to the embodiment of the present invention, the ring body 1, the washer member 2, the plug body 5, the nut member 9 and the spacer pipe 10 are used.
As shown in FIG. 1, the spacer pipe 10 is fitted onto the end of the pipe material P, and the spacer pipe 10 is
2, the ring body 1 is externally fitted so that the small diameter portion side is the end portion side of the pipe P, and the narrow diameter portion side of the ring body 1 is inserted into the throttle hole 3 of the plug body 5, and then, as shown in FIG. As shown in FIG. 3, by tightening the nut member 9, the ring body 1 is installed in the throttle hole 3 to squeeze the spacer pipe 10, and the spacer pipe 10 is pressed against the peripheral surface of the pipe material P.

That is, the end portion of the pipe material P is shown in FIG.
As shown in FIG. 5, the ring body 1 whose periphery is pressed against the throttle hole 3 of the stopper body 5 is sealed by being bitten into the peripheral surface of the pipe material P via the spacer pipe 10. And
The above-mentioned burst test is performed by applying pressure water from the end portion of the pipe material P on the unsealed side.

However, according to the method of the above-mentioned embodiment of the present invention, the pipe material P can be obtained without using special processing such as welding.
It is possible to mechanically simply and quickly seal the end of the plug and firmly seal it so as to withstand a high test pressure.

Even if it is difficult to make the ring body 1 bite into the pipe material P due to a large gap between the inner diameter of the ring body 1 and the outer diameter of the pipe material P, the thickness of the spacer pipe 10 By adjusting the thickness by exchange or the like, the above gap can be reduced, and the spacer pipe 10
It is possible to cause the ring body 1 to bite into the pipe material via the.

Although the embodiment of the present invention has been described above, the washer member 2 does not necessarily have to be interposed, and the ring body 1 can be directly pressed by the lower surface of the bag-shaped portion 7 of the nut member 9.

[0019]

As described above, the plugging method for the burst test pipe material according to the present invention comprises a tapered ring body,
A plug body having a throttle hole for inserting the small diameter side of the ring body,
A nut member that is screwed into the plug body and narrows the ring body into the throttle hole, and a spacer pipe that is externally fitted to the pipe material are used. By fitting the ring body to the pipe end side, further inserting the narrow diameter side of the ring body into the throttle hole of the plug body and tightening the nut member, the ring body is installed in the throttle hole and the spacer pipe is installed. The pipe material is narrowed through the plug, and the end portion of the pipe material is mechanically easily and quickly sealed without using any processing such as welding, and it is firmly sealed so that it can withstand high test pressure. Further, even if it is difficult to make the ring body bite into the pipe material because there is a gap between the ring body and the pipe material, it is possible to reduce the gap by changing the wall thickness of the spacer pipe. , In which a marked effect that it is possible to bite into the ring body to the pipe member through the spacer pipe.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an implementation state of a method for plugging an end portion of a pipe material according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a state after performing the same method.

FIG. 3 is an exploded perspective view of various members used in the method.

[Explanation of symbols]

 1 Ring body 2 Washer member 3 Drawing hole 4 Male screw part 5 Plug body 6 Female screw part 7 Bag-shaped part 8 Hole part 9 Nut member 10 Spacer pipe P Pipe material

Claims (1)

[Claims] 1. A tapered ring body into which a pipe material is inserted and a bottomed throttle hole into which a small-diameter portion side of the ring body is inserted, and an external thread portion coaxial with the throttle hole on the outer surface. A plug member having, and a nut member having a bag-shaped female thread portion that is screwed with the male thread portion of the plug body, and having a hole portion into which the pipe material is inserted and inserted at the center of the bag-shaped portion, A spacer pipe externally fitted to the pipe material and inserted into the ring body together with the pipe material is used, and the spacer pipe is externally fitted to the end portion of the pipe material, and the ring body is fitted to the spacer pipe at the small diameter portion side. By fitting the ring body to the pipe end side, further inserting the narrow diameter side of the ring body into the throttle hole of the plug body and tightening the nut member, so that the ring body is installed in the throttle hole. Squeeze the spacer pipe, and use this spacer pipe to A method for plugging an end portion of a pipe material for burst test, which comprises press-contacting a surface.