JPS5952984B2 - Annular member fixed on piping - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to ultrasonic flaw detection of piping in nuclear power plants, etc.
In particular, it relates to annular guide rails for remote automatic ultrasonic flaw detection equipment.

In nuclear power plants, pressure vessels, coolant piping, etc. are periodically inspected for flaws, and ultrasonic flaw detection is the most suitable and widely used non-destructive testing method.

In this case, flaw detection was mainly carried out manually, but due to the harsh working environment such as radiation exposure and the dispersion of data among inspectors, a remote automatic ultrasonic flaw detection device became necessary. Currently, this development is progressing in various fields, but there are difficult functional aspects such as weight, size, scanning accuracy, and attachment/detachment time, as well as performance aspects such as flaw detection accuracy, and there has been no product that satisfies these requirements. For example, regarding the weight issue, when workers carry a remote automatic ultrasonic flaw detection device depending on the inspection location, they may have to climb up and down a ladder while holding the device, or pass through a group of pipes with narrow and poor footing. Because it is necessary to carry it, it is about 10 times that one person can carry it.
The weight must be less than kg. Furthermore, when the flaw detection device is run along the circumference or axial direction of the pipe, its height is limited due to the distance between the flaw detection device and adjacent devices. In addition, regarding the issue of scanning accuracy, by being able to smoothly move the contact to a desired position on the pipe or at a desired angle, the flaw detection performance for determining the position, size, depth, etc. of flaws is greatly improved. Furthermore, in order to minimize radiation exposure of workers, it is necessary to shorten the working time at the inspection site as much as possible. For this reason, it is desirable to have a one-touch mechanism that can shorten the time required to attach and detach the flaw detection device to and from the piping. When moving a flaw detection device along the circumference of a pipe, there are two main methods: (1) a method in which the device runs directly on the pipe, and (2) a method in which the device runs on a guide rail attached to the pipe. These methods have advantages and disadvantages; for example, in the case of (1), the size and weight can be reduced by the amount of the guide rail, but there is a problem with accuracy in terms of position detection, and in the case of (2), this Suddenly it becomes the opposite. Currently, development is progressing in various fields (2)
) method. The reason for this is that small size and light weight are important, but more importantly, the problem of position detection accuracy is directly linked to a fatal flaw in flaw detection performance. For this reason, considerable effort has been put into the development of guide rails, but at present there is no one that is superior in terms of size, weight reduction, attachment/detachment time, clamping method, etc. Generally used guide rail mounting methods include (a) placing an elastic body such as a rubber leaf spring between the piping and the guide rail, and (b) placing multiple screws, etc. between the piping and the guide rail. Typical methods include single-acting or interlocking and fixed systems. Method (a) has the advantage of being mechanically simple, but since the force in the axial center direction is obtained by the force in the circumferential direction when tightening,
Although it was inefficient and required a very large force, it had the disadvantage of a weak tightening force. In addition, although the method (b) provides a large tightening force, it has disadvantages such as requiring tools, requiring a long attachment/detachment time, and being mechanically complex, making it higher than the pipe surface. If you explain it in more detail with a drawing,
It consists of a guide rail 2 attached to the pipe 1, which is the object to be inspected in Fig. 1, and a rubber plate 9 in between to improve the contact between the two. By running the pinion] 1 on the rack 12 installed on the guide rail 2, the probe 4 installed at the tip of the drive device 3 moves along the circumference of the pipe 1 in the circumferential direction Y. Can move.

Here, the rollers 6 and the holding mechanism 7 are driven by attaching a drive device 3 to the guide rail 2. On the other hand, the axial movement of the pipe 1 is achieved by moving the probe 4 attached to the tip of the arm 5 (not shown), which has a drive mechanism built into the drive device 3 that is different from that in the circumferential direction. It can be moved in the axial direction X. Here, the support column 8 is provided to enable the probe 4 to run smoothly on the piping surface with a constant pressure. In this way, the probe 4 is generally moved in the circumferential direction and axial direction near the welded part 0 to detect flaws such as cracks. FIG. 2 is an enlarged view of the guide rail in FIG. 1, and the guide rail 2 is attached to the circumference of the pipe 1 via a rubber plate 9.
The guide rail 2 has a joint 21A for connecting the hinge 20 that serves as the base point of the open/closed state and the divided guide rail 2.
, 21B and a ring 22 are attached.

Usually, this joint is a type of joint that has both fixing and tightening functions, such as a snap lock, but since the distance to squeeze is long and a considerable amount of tightening force is required, special tools are sometimes used. Furthermore, the guide rail 2 is provided with a rack 12 for the driving device to run on, and the piping 1
When the guide rail 2 is attached to the rack 2, the screw threads of the rack 2 must match perfectly. For this reason, the joints 21A and 21B must not only have no looseness, but also have the elasticity to allow the guide rail 2 to be completely clamped to the pipe 1 while the rubber plate 9 is relatively easily contracted when tightened. Certain things are required. but,
In reality, it is difficult to completely eliminate play in the joints 21A, 21B of snap locks and the like. Furthermore, while it is necessary to be flexible when tightening to the rubber plate 9, this would require contradictory requirements such as increasing the elasticity when attached, which is actually impossible. moreover,
It is necessary for the rubber plate 9 to expand and contract to some extent when clamping, and for this reason the thickness of the rubber plate 9 must be increased, but as a result, the height of the guide rail 2 from the surface of the pipe gate 1 is It's going to be big. There are examples of using leaf springs instead of rubber plates, but they have the same drawbacks as rubber plates.

The purpose of the present invention is to provide a guide rail for running an ultrasonic flaw detection device that can be easily attached to and removed from piping, clamped and released with a simple operation, and further improved the running performance of piping. To provide a guide rail whose height from the surface can be made extremely low.

In the present invention, the attachment/detachment to the piping and the clamp are completely separated, and the attachment/detachment is performed by one-touch operation of a lever, and the clamping and release are performed using a rubber tube inserted between the guide rail and the piping and a metal fitting to prevent sideways shaking. The above problem was solved by introducing and removing air pressure into the rubber tube.

FIG. 3 is a perspective view showing an embodiment of the guide rail and its attached mechanism for causing the ultrasonic flaw detection device of the present invention to run along the circumference of the pipe, and shows the guide rail in an open state.

The guide rail 2 includes a rattle 12 for allowing the ultrasonic flaw detection device to run along the circumference of the pipe, and connecting portions 30A and 30.
B, and insert the deformable pin 27 into the pin hole 33, then operate the handle 28 to insert the deformable pin 27 into the pin hole 3.
The guide rail 2 is comprised of a mechanism for attaching the guide rail 2 to the piping in an annular manner so that the guide rail 2 does not come out from the pipe, and a hinge 20 that is the center of operation of the guide rail 2 in the opening and closing states. In addition, as a mechanism for clamping the guide rail 2 attached to the piping as described above, air pressure is applied to the rubber tube 24, the metal fitting 25 for preventing the piping from swinging in the axial direction, and the rubber tubes 24 arranged in multiple pieces. Branch pipes 23A and 23B for dispersion
and a manual air pump 3 to pump air into it.
Consists of 2. When air pressure is not being applied to the rubber tube 24, it is desirable to have 20 to 30% of the outer diameter of the rubber tube 24 crushed by the metal fitting 25, and in this position, connect the elongated hole 3 of the metal fitting 25 with the guide. It is necessary to set the bolts 26 of the rail 2 in advance. In this case, the dimensions of the circle inscribed in the metal fitting 25 are:
If the guide rail is the same as or larger than the pipe diameter, the guide rail can be easily attached to the pipe without requiring force. However, even if the rubber tube 24 is somewhat smaller than the pipe diameter, it can be attached with a small force because the rubber tube 24 has sufficient flexibility. After this, when clamping the guide rail to the pipe, operate the valve 35, which normally opens when pressed in the closed state, and open it, then squeeze the air pump 32 to supply air to the rubber pipe 24. Rubber tube 2 when pumped
4 expands and pushes the metal fitting 25, it moves toward the pipe along the elongated hole 31 of the metal fitting 25 and presses it strongly, so that the guide rail 2 can be completely clamped to the pipe. In this case, just squeezing the air pump 32 two or three times will provide enough force to clamp it to the pipe. The guide rail shown in FIG. 3 is of a balanced type drive system as shown in FIG. 4, unlike the guide rail of the enclosing type shown in FIG. 1. That is, the driving devices 3A and 3B are divided and arranged so as to face the center of the guide rail 2. These connections are made using the arm 50, and the driving device 3B moves the arm 5 in the circumferential direction, and the driving device 3A moves the arm 5 to travel in the axial direction. This allows the probe 4 to move freely in the circumferential direction and the axial direction. Joining part 30 in Fig. 3
In order to explain the parts A and 30B in more detail, FIG. 5 shows the parts A and 30B enlarged.

FIGS. 5A and 5B are a plan view and a side view of the guide rail. When the guide rail is attached to the pipe, the rack 12 attached to the outer circumferential surface of the guide rail 2 is connected to the coupling part 41 and the other coupling part 42. , 43 are combined to form a ring. In this case, in order for the pinion of the drive to run on the rack 12, it is necessary to ensure that the tooth profiles perfectly match. Further, the running rollers of the drive device run on running surfaces 40A and 40B provided on both sides of the rack 12''.Guide rail 2
When the deformable pin 27 is inserted into the pin hole 44 and the handle 28 is rotated, the deformable pin 27 that is coaxial with the deformable pin 27 rotates and can be fixed in the pin hole 33. To explain this principle in detail, it is as shown in FIG. 6, and in the state before the guide rail 2 is connected, the deformed pin 27 whose part that enters the pin hole 33 has a semicircular cross section is a pin with an open end. It can be inserted into the hole 33. In this case, the angle of the deforming pin 27 is set by the handle 28. FIG. 7 shows the connected state, and if the handle 28 is rotated when the deformable pin 27 enters the pin hole 33, the deformable pin 27 connected thereto will rotate and will not come out from the opening of the pin hole 33. The guide rails 2 can be completely connected. On the other hand, the configuration of the hinge portion that serves as the axis for opening and closing the guide rail 2 is as shown in FIG. FIG. 8 shows a side view of the same part as the plan view. The divided guide rails 2A and 2B are connected by a hinge pin 45, and the guide rails are opened and closed by rotating around this as an axis. I can do j. In this case, in order to rotate the hinge pin 45 as an axis, it is necessary to provide reliefs 46, 48, and 49 at the joint portions of the guide rails 2A and 2B.
Therefore, when the pinion runs on the rack 12, the reliefs 46, 49, etc. of the rack 12 become obstacles. Therefore, by separating the connecting part of the rack 12 into two positions and making it possible for the pinion to run on the other rack 12 even if it falls off due to escape from one, the pinion can rotate smoothly on the rack 12 at the joint part. You can drive while In addition, the running surfaces 40A and 40B on which the rollers of the drive device run also have escape points 4.
8, etc., by dividing the running surfaces 40A, 40B near the center and allowing the rollers to run through the concave portion created by the relief 48, thereby allowing smooth running. To explain the principle of fixing the guide rail after attaching it to the piping, FIG. Piping] and guide rail 2 to transform into
The positional relationship between the guide rails 2 and 2 is in a changing state, that is, the guide rail 2 is not fixed. However, for this reason, when attaching the divided guide rail 2 to the piping 1, it is possible to form a circular guide rail without applying much force. Thereafter, when air pressure is applied to the rubber tube 24, the result becomes as shown in FIG. 10, and the expansion of the rubber tube 24 pushes the metal fitting 25 in the direction of the pipe 1, and the guide rail 2 receives the reaction force.
Therefore, the guide rail 2 can be fixed to the pipe 1. Here, the metal fitting 25 is pressed against the piping 1 by the force of the rubber tube 24, and by suppressing both sides of the guide rail 2, the movement of the piping 1 in the axial direction is eliminated, and the metal fitting 25 is simply applied to the pressing force against the piping surface. It's meant to be done. When removing the guide rail from the piping, open the valve 35 between the air pump 32 and the branch pipe 23A shown in FIG. If you rotate the pin hole 33
The deformable pin 27 can be easily taken out.

According to the present invention, the present invention has the following features compared to conventional guide rails, and is significantly improved in terms of operability, weight reduction, economical efficiency, workability, reliability, etc.

(1) Since the installation of the guide rail to the piping and the clamp operation are separated, installation can be done with just a simple handle operation.

The subsequent clamping operation can be done reliably on the piping by simply operating a manual air pump. (2) The vibration after clamping, which is a drawback of flexible materials such as rubber, can be reliably clamped by the combination of a vibration stopper and air pressure.

(3) Since the structure of the clamp mechanism is extremely simple, the thickness of the guide rail can be made thinner and the space required for it can be reduced, so the height of the guide rail from the piping surface can be made extremely low. .

Since the movable part has a simple structure, it is easy to manufacture, and commercially available products such as rubber tubes can be used, making it economically advantageous. The simple structure of the moving parts reduces the failure rate and improves reliability. (4) Installation;
In the case of clamping, no tools are required, and one worker can clamp the pipe to the pipe in just a few tens of seconds.

(5) Being able to completely clamp the guide rail to the piping can improve the running accuracy of the ultrasonic flaw detector that runs on it.

(6) Since the deformable pin or the like is used, the thickness of the guide rail can be reduced, and when the guide rail is formed into a ring shape, there is no protrusion on the running surface of the joint, making it smooth and simple.

(7) The problem was solved by making the joint part uneven so that the pinion could run smoothly over the hinge part of the rack.

Although the guide rail of a balanced type drive device has been described as an embodiment of the present invention, the present invention is not limited to this, and can be applied without any problems to the enclosing type drive device described in the conventional example. However, it is not limited by the type of these guide rails. In the present invention, a rubber tube is used as the deformable material, but any material that can be deformed by external pressure, such as a rubber bag, metal or non-metallic bellows, etc., can be used without any problems. Further, the metal fittings that slide according to the deformation of the rubber tube of the deformable material are not limited to the shape and method described above, and it is effective to change them depending on the purpose. Although deformable pins are used to attach the guide rail to the piping, the present invention is not limited to this, and there is no problem in using other coupling means.

In this explanation, we have described how to pressurize the rubber tube from atmospheric pressure, but for example, if you release the air in the rubber tube in advance to create a light vacuum, the rubber tube will become plate-shaped and will be easier to install. This makes it possible to largely absorb dimensional errors in piping.

Furthermore, since the space of the rubber tube portion of the guide rail can be reduced, the height of the guide rail can be further reduced. Although air pressure is used in this description, other gases, liquids, etc. can also be used.

For example, it is also possible to pressurize using a small Freon cylinder. In the present description, a case has been described in which the guide rail is divided into two semicircular parts, but it is also effective to increase this number depending on the purpose, and the guide rail is not limited to two parts.

The material of the guide rail is usually a lightweight metal such as aluminum, but since the structure is simple, a non-metallic material such as synthetic resin can also be used.

The guide rail of the present invention is not limited to ultrasonic flaw detection equipment, but can also be fully utilized in automatic welding machines, etc., for example.

Although it is said that it is best to collapse the rubber tube by 20 to 30%, this is not unambiguous because it is related to the flexibility and expansibility of the deformable material such as the rubber tube, as well as the structure and method.

Although the case where a rack is used as the guide rail has been described, it is needless to say that the present invention is not limited to this, and for example, a chain or the like can be used without any problem.

[Brief explanation of the drawing]

Figure 1 is a diagram for explaining the configuration of an ultrasonic flaw detection device, Figure 2 is a diagram for explaining the configuration and operation of a conventionally commonly used guide rail, and Figure 3 is a diagram for explaining the configuration and operation of a conventionally commonly used guide rail. FIG. 4 is a perspective view illustrating an embodiment of the present invention, and FIG. 4 is a diagram illustrating a balanced ultrasonic flaw detection device.
Figure 5 is a diagram for explaining the opening of the guide rail, Figures 6 and 7 are diagrams for explaining the attachment state of the deformable pin, and Figure 8 is a diagram for explaining the hinge part of the guide rail. FIG. 9 and FIG. 10 are diagrams for explaining the functions of the clamp. 2... Guide rail, 12... Rack, 20... Hinge, 23A, 23B... Branch pipe, 24... Rubber tube, 25... ...Metal fittings,
26... Bolt, 27... Deformed pin,
28...Handle, 30A, 30B...
・Joining part, 31...Elongated hole, 32...Air pump, 33...Pin hole, 35...
·valve.

Claims (1)

[Claims] 1. In an annular member that is configured so that a part of the annular member can be separated and connected and fixed on the piping, a contracting member disposed between the separating and connecting ends of the inner circumferential surface of the annular member, and a contracting member at several places on the annular member A piping system comprising: a holding member that holds a member and can move only toward the center of the annular member; and a pressure feeding member that introduces air or liquid from a part of the contracting member to expand the contracting member. An annular member fixed on top.