JPH07174253A - Radiographing method for ball valve - Google Patents

Abstract

PURPOSE:To facilitate radiographing of a welded portion of a all-weld type ball valve, where it is imposible to prepare for photographing by, e.g. extending a hand, by providing a jug having an arm member connected at the center thereof to the tip of a rod member by a pin, and rotating the rod member together with a radiation source mounted on the rod member. CONSTITUTION:A film 14 is disposed around the whole or required part of a welded portion A for connecting a body 2 to a body cap 3 of an all-weld type ball valve 1 for radiographing. A jig 8, where the centeer of an arm member 10 is oscillatably conncted to the tip of a rod member 9 by a pin 10, is fitted to the valve 1, and then, the arm member 10 is fixed to a ball 6. Thereafter, an operating rod 15 is operated so that the arm member 10 is oscillated to incline the ball 6. In this state, the rod member 9 is rotated, a radation source 13 is rotated integrally with the rod member 9, and the ball 6 is rotated together with the arm member 10. With part of the ball 6 not interposed between the radiation source 13 and the welded portion A, the whole or necessary part of the welded portion A is subjected to radiographing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiographing method for radiographing a welded portion of a fully welded ball valve in which a body and a body cap are welded and connected.

[0002]

2. Description of the Related Art A welded portion between a body and a body cap of an all-welded ball valve may cause a serious accident such as leakage of internal fluid if it is defective. Therefore, it is necessary to strictly inspect this weld. Particularly in high pressure or nuclear ball valves, it is required to inspect the entire weld line for radiation. However, the radiation inspection of the welded portion between the body and the body cap of the all-welded ball valve must be carried out with the ball installed in the body, and this ball becomes an obstacle and is extremely difficult. It was almost impossible to completely inspect the entire weld line.

By the way, as a conventional example, Japanese Examined Patent Publication No. 59-11.
No. 792 can be mentioned, which relates to the structure of an all-welded ball valve capable of completely performing a radiation inspection on the entire line of a welded portion connecting a body and a body cap. The ball can be tilted in any direction so as not to get in the way. However, even if the valve has such a structure, the radiation tube or film for radiography cannot be mounted at a required position inside the valve due to the long or thin sleeve tube, and therefore, the radiation inspection is performed. There were things I couldn't do. Further, in order to inspect the entire line of the welded part for radiation inspection, the inclination direction of the ball must be changed many times so as not to interfere with the photographing, and it is very troublesome work each time. .

[0004]

SUMMARY OF THE INVENTION According to the present invention, as described above, the ball valve is structured so that the ball can be freely tilted, and the whole line of the welding line connecting the body and the body cap is radiographed. Even if you can
A ball to solve the trouble that the sleeve tube is connected to this valve and the sleeve tube is long or thin and can not be prepared for radiography, or that the setup change is required during the radiography and it is a troublesome work. A method for radiography of a bulb is provided.

[0005]

In order to achieve the above object, the present invention is an all-welded ball valve in which a body and a body cap are welded and connected to each other. A jig formed by connecting pins so that it could be swung on the same plane as the rod member was fixed to a radiation source for radiography at a fixed position of the rod member, and the arm member was attached to the rod member. The arm member is inserted into the central portion of the ball in an open state from one flow path opening of the ball valve at a substantially right angle with respect to the ball valve, and the upper and lower stems are removed and provided at the bottom of the stem hole of the ball. In addition, a bolt passed through both holes or one of the holes is screwed into the arm member to fix the arm member to the ball, and the arm member is swung by a certain angle, and the welded portion connecting the body and the body cap and the above Part of the ball is interposed between the The odd, mounting the film on the outside of the weld, by rotating the rod member all or part of the weld was as radiography.

This method is extremely effective when the ball valve is a valve with a sleeve tube and when the ball tube is a valve in which a person cannot enter the sleeve tube or reach for the hand to prepare for photographing. . Further, it is preferable that the rod member of the jig is supported at an intermediate position, and the arm member is swung by using a dedicated operating rod.

[0007]

Since the present invention is constructed as described above, first of all, a film is formed on the entire or a necessary portion of the welded portion connecting the body and the body cap of the all-welded ball valve for radiography. Deploy. Next, insert the jig with the arm member at a right angle to the rod member, and insert it from one flow path opening of the ball valve, or from the mouth of the sleeve tube if equipped with a sleeve tube, and place the arm member in the central portion of the ball with the valve open. Located in.
In this case, the arm member is made to have a length matching the inner diameter of the flow path of the ball, and the radiation source is fixed at a predetermined fixed position of the rod member.

Remove the upper stem and the lower stem,
The ball is supported by the seat assembly member, and the bolt is inserted into the arm member by passing a bolt through one or both holes provided in the bottom of the stem hole to fix the arm member to the ball.

In this state, a dedicated actuating rod is used to tilt the ball by swinging the arm member at a certain angle with respect to the rod member so that the ball portion does not intervene between the radiation source and the welded portion. When the rod member is rotated in this state, the radiation source fixed to the rod member is also rotated, the ball is also rotated together with the arm member, and the ball portion is not always interposed between the radiation source and the welded portion. Therefore, by rotating the rod member, the entire line of the welded portion or a necessary portion can be easily radiographed.

Since this jig can be made in accordance with the size of the ball valve and the length of the sleeve tube, it is suitable for ball valves that cannot be prepared for shooting by people entering or reaching. It is extremely effective to apply the radiation imaging method of the invention.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a ball valve radiation imaging method according to the present invention will be described below. 1 is a sectional view, and FIG. 2 is a partial sectional view showing a state in which the ball is tilted from the state of FIG. In the drawings, 1 is a fully welded ball valve, 2 is a body, 3 is a body cap, 4 and 5 are sleeve tubes, 6 is a ball, 7 is a seat assembly member, 8 is a jig, and 9
Is a bar member, 10 is an arm member, 11 is a pin, 12 is a bolt,
13 is a radiation source, 14 is a film, 15 is an actuating rod,
16 is an intermediate support. A is a welded portion connecting the body 2 and the body cap 3, and B and C are welded portions connecting the body 2 and the sleeve pipe 4 and between the body cap 3 and the sleeve pipe 5.

The jig 8 has an arm member 10 at the tip of the rod member 9.
The central part of the pin is pin-connected by the pin 11 so that it can swing on the same plane as the rod member 9. The radiation source 13 for radiography is fixed at a fixed position suitable for imaging as shown in the drawing of the rod member 9, and the arm member 10 is perpendicular to the rod member 9 as shown in FIG. Then, the jig 8 is inserted from one flow path opening of the ball valve 1, in this case, the opening 5a of the sleeve tube 5 so that the arm member 10 is located at the center of the ball 6. In this case, the intermediate support 16 is also inserted if necessary.

The upper and lower stems are removed and the stem holes 6a, 6 of the ball 6 supported by the seat assembly member 7 are removed.
The bolt 12 passing through the holes 6c and 6d provided at the bottom of b is screwed into the arm member 10 to fix the arm member 10 to the ball 6.
In this case, the arm member 10 may be fixed by screwing the bolt 12 into both or one of the holes 6c and 6d. It should be noted that the holes are included even when they are formed in both or one of them. Next, press the operating rod 15 to press the arm member 1.
0 is swung by a certain angle as shown in FIG. Therefore, the ball 6 tilts as shown in FIG.
The part of the ball 6 is not interposed between the part 3 and the part 3. The film 14 is attached to the outside of the welded portion A. After doing so, the rod member 9 is rotated to radiograph the whole or part of the welded portion A.

Next, the operation of the above embodiment will be described. First, the film 14 is attached to the whole or a required portion of the welded portion A connecting the body 2 and the body cap 3 of the all-welded ball valve 1 to be subjected to radiography. Next, as described above, the jig 8 is inserted into the valve 1, the arm member 10 is fixed to the ball 6, and then the arm member 1
0 is rocked and the ball 6 is tilted.

When the rod member 9 is rotated in this state, the radiation source 13 fixed to the rod member 9 is also rotated together, the ball 6 is also rotated together with the arm member 10, and the space between the radiation source 13 and the welded portion A. The portion of the ball 6 does not always intervene. Therefore, by rotating the rod member 9, the entire welded portion A is
Alternatively, a necessary part can be easily radiographed.

This jig 8 has the same size as the ball valve 1,
Since it can be created according to the length of the sleeve tubes 4 and 5,
It is extremely effective when applied to a radiation imaging method of a ball valve in which a person cannot enter or reach out and prepare for imaging.

[0017]

As described above, according to the method for radiography of a ball valve of the present invention, a sleeve tube is attached to the all-welded ball valve, and the sleeve tube is long or thin, so that it is ready for radiography. Even with a valve that cannot be used, radiography can be easily performed simply by rotating the rod member without setting up the whole or a required part of the welded portion connecting the body and the body cap. A convenient method can be provided.

[Brief description of drawings]

FIG. 1 is a sectional view for explaining an embodiment of the present invention.

FIG. 2 is a partial cross-sectional view showing a state in which the ball is tilted from the state shown in FIG.

[Explanation of symbols]

 1 Ball valve 2 Body 3 Body cap 4, 5 Sleeve tube 6 Ball 6a, 6b Stem hole 6c, 6d Hole provided in the bottom of the stem hole 8 Jig 9 Bar member 10 Arm member 12 Bolt 13 Radiation source 14 Film 15 Operating rod 16 Intermediate support A Welding part that connects the body and the body cap

Claims (4)

[Claims] 1. A fully welded ball valve in which a body and a body cap are welded and connected to each other so that a central portion of an arm member can be swung on the same plane as the rod member at a tip end portion of the rod member. A jig formed by pin connection to the rod member was fixed to the radiation source for radiation imaging at a fixed position of the rod member, and its arm member was made substantially perpendicular to the rod member, and one of the flow passage ports of the ball valve was formed. This arm member is inserted into the center of the ball in the valve-opened state, and bolts passed through both or one of the holes provided at the bottom of the stem hole of the ball from which the upper and lower stems have been removed are attached to the arm member. The arm member is fixed to the ball by screwing it in, and the arm member is swung by a certain angle so that the ball portion does not intervene between the welded portion connecting the body and the body cap and the radiation source. And attach the film to the outside of this weld, A radiographic imaging method for a ball valve, characterized in that the rod member is rotated to perform radiographic imaging of all or part of the welded portion. 2. The method of radiographic imaging of a ball valve according to claim 1, wherein the ball valve is a valve with a sleeve tube. 3. The radiographic imaging method for a ball valve according to claim 1, wherein the rod member of the jig is appropriately supported in the middle. 4. The radiation imaging method for a ball valve according to claim 1, wherein the arm member is swung by using a dedicated actuating rod.