JP6909768B2 - How to lift and hang heavy objects - Google Patents

Description

The present invention relates to a method for lifting and lowering a heavy object, particularly a method for lifting and lowering a heavy object using a hydraulic jack.

As an example of a method of lifting and suspending a heavy object with respect to a storage container, Patent Document 1 discloses a method of lifting and suspending a measurement plug as a heavy object with respect to a cask as a storage container in a nuclear facility. There is. Hereinafter, a method of lifting and lowering the measurement plug will be described with reference to FIG.

FIG. 3 is a partial schematic cross-sectional view showing a nuclear facility.

In FIG. 3, 21 is a measurement plug inserted into the shield floor 22 of the nuclear facility, 23 is a work floor installed above the shield floor 22, and 24 is a cask installed above the work floor 23. Is a hanging bracket installed on the measuring plug 21, 26 is a lifting pedestal installed above the cask 24, and 27 is a hydraulic jack similar to the hydraulic jack 1 in FIG. 1 installed on the lifting pedestal 26. It is a hoisting mechanism using 29. As the hoisting mechanism 27, for example, the one disclosed in Patent Document 2 is used.

In the nuclear facility configured as described above, the replacement of the measurement plug 21 is performed as follows after the output operation of the nuclear facility is completed.

Although two measuring plugs 21, a hanging metal fitting 25, and the like are shown in FIG. 3, they are described for explaining the lifting of the measuring plugs as described above, and usually one of them is measured. The plug exists.

First, in a state where the upper measurement plug 21 shown in FIG. 3 does not exist in the cask 24, the cask 24 on which the hoisting mechanism 27, the lifting stand 26, etc. are installed is lifted by the measuring plug 21 to be lifted, that is, FIG. The lower measurement plug 21 shown in the above is moved onto the work floor 23. Then, the rope 28 suspended from the hoisting mechanism 27 is connected to the hanging metal fitting 25. Next, the hoisting mechanism 27 is operated to wind up the rope 28, whereby the measuring plug 21 is lifted from the shield floor 22 in the direction indicated by the arrow in the drawing and stored in the cask 24. After that, the cask 24 is carried out of the nuclear facility building together with the measurement plug 21. Then, the cask 24 containing the new measurement plug 21 is carried into the nuclear facility building, and the operation opposite to the above-mentioned lifting operation is performed to suspend the measurement plug 21 from the inside of the cask 24 and inside the shield floor 22. Insert in.

As described above, the measurement plug 21 is replaced.

Japanese Unexamined Patent Publication No. 11-109071 Japanese Unexamined Patent Publication No. 2014-214025 Japanese Unexamined Patent Publication No. 10-59691

According to the method shown in FIG. 3, for example, when the deviation of the center of gravity of the measurement plug 21 is small, the measurement plug 21 can be easily lifted and lowered, but when the deviation of the center of gravity of the measurement plug 21 is large, the measurement can be performed. When the plug 21 is suspended from the inside of the cask 24 and inserted into the shielding floor 22, the measuring plug 21 may come into contact with at least one of the cask 24 and the shielding floor 22.

The cause of the measuring plug 21 coming into contact with at least one of the cask 24 and the shielding floor 22 is not only the deviation of the center of gravity of the measuring plug 21, but also the hoisting or lowering speed of the rope 28 by each hoisting mechanism 27, or the feeding or feeding speed. There is an inclination of the measuring plug 21 caused by the variation of the above. If the measuring plug 21 is tilted beyond the limit value, the measuring plug 21 may come into contact with at least one of the cask 24 and the shielding floor 22.

Even when the measurement plug 21 is lifted from the shield floor 22 and stored in the cask 24, the measurement plug 21 may come into contact with at least one of the cask 24 and the shield floor 22.

As described above, there has been a problem of preventing the measurement plug 21 from coming into contact with at least one of the cask 24 and the shielding floor 22 and applying a large load.

Therefore, when the measuring plug 21 is lifted and lowered with respect to the cask 24, it is possible to prevent the measuring plug 21 from coming into contact with at least one of the cask 24 and the shielding floor 22 and applying a large load. It has been desired to develop a method for lifting and lowering an object.

As a method of achieving this, the jack pressure of the hydraulic jack 29 of the hoisting mechanism 27 is converted into the load of the measuring plug 21, and when this load exceeds the limit value, the hydraulic pump supplies the hydraulic jack 29 to the operation. The method of stopping the oil was taken.

However, even if the controller issues a command to stop the supply of hydraulic oil to the hydraulic jack 29 to the hydraulic pump, it takes time until the operation of the hydraulic jack is completely stopped due to the overshoot of the hydraulic pump. There was room for improvement. Overshoots of hydraulic pumps occur especially when hanging heavy objects.

These problems occur not only when the measuring plug 21 is lifted and hung with respect to the cask 24, but also when a heavy object is lifted and hung in a state where other members are present around the cask 24.

Therefore, an object of the present invention is to prevent a heavy object from coming into contact with other members and applying a large load when the heavy object is lifted and lowered by a hoisting mechanism provided with a hydraulic jack. It is an object of the present invention to provide a method for lifting and lowering a heavy object.

The present invention has been made to achieve the above object, and is characterized by the following.

The invention according to claim 1 is a method in which a plurality of hoisting mechanisms including a hydraulic jack operated by a hydraulic pump are controlled by a controller to lift and lower a heavy object, wherein the heavy object is used in a nuclear power plant. It is a structure inside the furnace, and the lifting load of the heavy object by the hydraulic jack is measured by a load meter, and when the heavy object is lifted, an abnormal value in which the lifting load of the heavy object exceeds a preset threshold value is set as the load. When the meter detects it, the controller issues a lifting stop command for the heavy object to the hydraulic pump, while the lifting load of the heavy object is less than a preset threshold when the heavy object is suspended. the outliers when the load meter is detected, the predetermined time a command to switch on the lifting side of the heavy hydraulic pump, and outgoing, the predetermined time is command issued to switch to the lifting side of the controller after it is, and it has the characteristics in the time der Rukoto until just before the heavy is lifted.

According to the second aspect of the present invention, the inclination angle of the heavy object is detected by an inclination meter, and when the inclination angle of the heavy object exceeds a preset limit value threshold, the operation of the hoisting mechanism is performed. It is characterized in that it is stopped once and the inclination angle of the heavy object is adjusted horizontally.

The invention according to claim 3 is characterized in that the load cell is a load cell.

The invention according to claim 4 is characterized in that three hoisting mechanisms are installed at 120 ° intervals in a plan view.

Invention of claim 5, before Symbol threshold, the a load value exceeding the limit value of the lifting load when lifting heavy objects, hanging load lower than the limit value of the hanging load during lowering It is a value, and the limit value is characterized in that it is a load value that damages the heavy object.

According to the present invention, when a hydraulic jack operated by a hydraulic pump is controlled by a controller to lift and lower a heavy object with respect to a storage container for the heavy object, the load of the heavy object by the hydraulic jack is measured. By reducing the overshoot of the hydraulic pump after detecting an abnormal value of the suspended load by the load gauge, it is possible to prevent heavy objects from coming into contact with other members and applying a large load. Can be done.

According to the present invention, the overshoot of the hydraulic pump can be reduced as follows.

When lifting a heavy object, if the load meter detects an abnormal value in which the lifting load of the heavy object exceeds a preset threshold value, the controller issues a command to stop the lifting of the heavy object to the hydraulic pump, while the heavy object is lifted. When the load meter detects an abnormal value in which the hanging load of a heavy object is less than a preset threshold value, the controller issues a command to the hydraulic pump to switch to the lifting side of the heavy object for a predetermined time. .. Thus, it is possible to reduce the overshoot of the hydraulic pump after the abnormal value of the suspended load is detected by the load meter, especially when the heavy object is suspended.

According to the present invention, when the load meter detects an abnormal value in which the lifting load exceeds a preset threshold value when lifting a heavy object, the controller issues a lifting stop command to the hydraulic pump, while lifting the heavy object. When the load meter detects an abnormal value in which the lifting load of the heavy object is less than the preset threshold when suspending the heavy object, the controller issues a command to the hydraulic pump to switch to the lifting side of the heavy object for a predetermined time. By emitting, a large braking effect can be obtained, and as a result, the overshoot of the hydraulic pump can be dramatically reduced.

Further, the inclination angle of the heavy object is detected by, for example, an inclinometer, and when the inclination angle of the heavy object exceeds a threshold value less than the limit value, the operation of the hoisting mechanism is temporarily stopped, and then the hoisting is performed. By adjusting the suspension height of the heavy object by the mechanism, the heavy object can be maintained horizontally, and the heavy object can be prevented from tilting and coming into contact with the storage container to apply a large load. be able to.

It is explanatory drawing of the method of lifting and lowering a heavy object of this invention. It is a block diagram which shows one Embodiment of the method of lifting and lowering a heavy object of this invention. It is a partial schematic sectional view showing a nuclear facility.

An embodiment of the method for lifting and lowering a heavy object according to the present invention will be described with reference to the drawings.

Here, a measurement plug of a nuclear facility will be described as an example of a heavy object, and a cask accommodating the measurement plug as a storage container will be described as an example. The same applies even when it is lowered.

FIG. 1 is an explanatory diagram of a method for lifting and lowering a heavy object according to the present invention, and FIG. 2 is a configuration diagram showing an embodiment of the method for lifting and lowering a heavy object according to the present invention. In FIG. 2, those having the same number as in FIG. 3 indicate the same thing.

In FIG. 1, reference numeral 1 denotes a hydraulic jack of a hoisting mechanism 27 (see FIG. 3) for lifting and lowering a measurement plug 21 (see FIG. 3) as a heavy object with respect to a cask 24 (see FIG. 3). In 1, it is described as a hydraulic jack 1. The hydraulic jack 1 is, for example, the hydraulic jack disclosed in Patent Document 3. 2 is a hydraulic pump that supplies hydraulic oil to the hydraulic jack 1, 3 is a controller that controls the operation of the hydraulic pump 2, 4 is an operation panel of the controller 3, and 5 is a continuous suspension load of the measuring plug 21. It is arranged at the lower part of the hydraulic jack 1 with a load meter (see FIG. 1) for measuring the purpose, and in this embodiment, it is composed of a load cell.

The operation panel 4, the controller 3, the hydraulic pump 2, the load meter 5, and the hydraulic jack 1 are each connected by a signal line (indicated by a dotted line in FIG. 1), and the hydraulic pump 2 and the hydraulic jack 1 are connected to each other. , The hydraulic hose 8 is arranged, and the hydraulic oil moves in and out of the hydraulic jack 1 by driving the hydraulic pump 2, and the hydraulic cylinder 9 of the hydraulic jack 1 moves up and down in FIG.

Here, the structure of the hydraulic jack 1 will be described with reference to FIG.

In FIG. 1, 6 is an upper gripping mechanism, 7 is a lower gripping mechanism, and the controller 3 is operated by the operation of the operation panel 4, and the rope 28 is connected to a heavy object (FIG. 3). (See) can be gripped and opened. The rope 28 is gripped and opened by opening and closing the grip 12 arranged in the upper gripping mechanism 6 and the grip 13 arranged in the lower gripping mechanism 7. The upper gripping mechanism 6 is configured to be able to move up and down with respect to the lower gripping mechanism 7 by using a hydraulic cylinder 9.

In the hydraulic jack 1 configured in this way, when lifting a heavy object, the hydraulic cylinder 9 is in the lower state (the upper gripping mechanism 6 is in the lower state) and the rope 28 is gripped by both gripping mechanisms 6 and 7. In this state (both grips 12 and 13 are closed), the rope 28 is opened (grips 12 are closed and 13 are open) in the lower grip mechanism 7, and the upper grip mechanism 6 is raised by the hydraulic cylinder 9. , It is lifted by one stroke of the hydraulic cylinder 9. After that, the lower gripping mechanism 7 grips the rope 28 (both grips 12 and 13 are closed), the upper gripping mechanism 6 opens the rope 28 (grips 12 open and 13 closed), and then the upper gripping mechanism 6 is returned to the original position. Lower to position. Then, the upper gripping mechanism 6 grips the rope 28 (both grips 12 and 13 are closed) to prepare for the next lifting. By repeating this operation, a heavy object can be lifted intermittently.

On the other hand, when suspending a heavy object, the hydraulic cylinder 9 is in the lower state (the upper grip mechanism 6 is in the lower state) and the rope 28 is gripped by both gripping mechanisms 6 and 7 (both grips 12 and 13 are closed). ), In the upper gripping mechanism 6, the rope 28 is opened (grips 12 are opened and 13 are closed), and the upper gripping mechanism 6 is raised by the hydraulic cylinder 9. After that, the upper gripping mechanism 6 is raised by one stroke, the rope 28 is gripped by the upper gripping mechanism 6 (both grips 12 and 13 are closed), and then the rope 28 is released by the lower gripping mechanism 7 (grip). 12 closed, 13 open). Then, if the upper gripping mechanism 6 is lowered, the heavy object is suspended by one stroke of the hydraulic cylinder 9. Then, the lower gripping mechanism 6 grips the rope 28 (both grips 12 and 13 are closed) to prepare for the next suspension. By repeating this operation, a heavy object can be suspended intermittently.

The grips 12 and 13 in the upper gripping mechanism 6 and the lower gripping mechanism 7 are opened and closed by a control signal from the controller 3. Further, the raising and lowering of the upper gripping mechanism 6 by the hydraulic cylinder 9 is performed by driving the hydraulic pump 2 and moving the hydraulic oil into and out of the hydraulic cylinder 9, and these are also executed by the control signal from the controller 3.

According to this one embodiment, it is possible to prevent the measuring plug 21 as a heavy object from coming into contact with the cask 24 and applying a large load as follows.

When the measurement plug 21 is lifted from the cask 24 by the hydraulic jack 1, the lifting load of the measuring plug 21 by the hydraulic jack 1 is measured by the load meter 5, and the lifting load of the measuring plug 21 exceeds a preset threshold value. When the load meter 5 detects the value, it is determined that the measuring plug 21 has contacted the cask 24, for example, and the load of the measuring plug has increased, and the controller 3 issues a command to stop lifting a heavy object to the hydraulic pump 2. Emit. That is, in order to stop the ascending of the hydraulic cylinder 9 of the hydraulic jack 1 to the hydraulic pump 2, an operation stop command is issued. Here, the stop command at the time of lifting means a command for stopping the drive motor (not shown) of the hydraulic pump.

On the other hand, when the measurement plug 21 is suspended from the cask 24 by the hydraulic jack 1, if the load meter 5 detects an abnormal value in which the suspension load of the measurement plug 21 is less than a preset threshold value, the measurement plug 21 is used. For example, it is determined that the load of the measuring plug has decreased due to contact with the cask 24, and the control 3 stops the lowering of the hydraulic cylinder 9 of the hydraulic jack 1, so that the operation of the hydraulic cylinder 9 is increased to the hydraulic pump 2. A command to switch to the lifting side of a heavy object is issued for a predetermined time so as to operate.

The predetermined time for suspending is immediately before the measuring plug 21 is lifted after the command to switch to the lifting side is issued (when the load returns to the threshold range and does not exceed the threshold value). It is time to.

The threshold value is a load value that exceeds the limit value of the lifting load when the measurement plug 21 is lifted, and is a load value that is less than the limit value of the hanging load when the measurement plug 21 is lifted. The limit value is a load value that damages the measuring plug 21. As a result, the overshoot of the hydraulic pump 2 after the detection of the abnormal value by the load meter 5 can be reduced, so that it is possible to prevent the measurement plug 21 from coming into contact with the cask 24 and applying a large load. Can be done.

When the lifting and hanging of a heavy object is stopped as described above, after the stop, the hoisting mechanism 27 is operated to correct the posture of the heavy object, the rope tension adjustment, and the hanging condition of the hanging bracket, and then again. , Lifting and hanging heavy objects.

In this embodiment, the case where the measurement plug 21 comes into contact with the cask 24 is mainly described, but the same applies to the case where the measurement plug 21 comes into contact with the shielding floor 22 (see FIG. 3).

Another embodiment of the method for lifting and lowering a heavy object of the present invention will be described with reference to FIG.

In FIG. 2, reference numeral 10 denotes an inclinometer installed on the hanging metal fitting 25 of the measuring plug 21, and the inclination angle of the hanging metal fitting 25 is the same as the inclination angle of the measuring plug 21. The inclinometer 10 detects the inclination of the measuring plug 21 in two directions (see FIG. 2) of XY. In FIG. 2, the X direction is the so-called horizontal direction in the left-right direction of the paper surface, and the Y direction is the vertical direction of the paper surface in the vertical direction with respect to the horizontal direction.

11 is different from the above-mentioned controller 3 which controls the hoisting mechanism 27 based on the inclination angle data of the measurement plug 21 detected by the inclinometer 10 to adjust the inclination angle of the measurement plug 21 horizontally. It is a controller of. Although the controller 11 and the controller 3 are not shown, they are connected to each other and can transmit data to each other. The tilt angle data of the tilt meter 10 is also transmitted to the controller 3.

In the above-described embodiment, when an abnormal value is detected, for this correction, for example, a worker operates the hoisting mechanism 27 to correct the posture of a heavy object, the rope tension adjustment, and the hanging condition of the hanging metal fitting. However, heavy objects are being lifted and hung again.

In this embodiment, when the lifting operation is stopped when the heavy object is lifted, the controller 11 raises the hoisting mechanism 27 based on the tilt angle data of the measurement plug 21 by the inclinometer 10 after the stop. By controlling, the inclination angle of the measuring plug 21 is adjusted horizontally. Then, after this, the lifting of the measuring plug 21 is continued.

When the hanging operation is stopped when the heavy object is hung, the controller 11 controls the hoisting mechanism 27 based on the tilt angle data of the measurement plug 21 by the inclinometer 10 after the stop. Then, the posture of the inclination angle of the measurement plug 21 is adjusted horizontally. Then, after this, the hanging of the measuring plug 21 is continued.

Yet another embodiment of the method for lifting and lowering heavy objects of the present invention will be described.

As a method of horizontally adjusting the posture of the measuring plug 21, in addition to the method using the inclinometer 10 described above, the distance from each hoisting mechanism 27 to the core upper mechanism 21 is measured by a wire encoder, and the distance between the hoisting mechanisms 27 is measured. When the deviation of the distance exceeds the threshold value less than the limit value, the hoisting mechanism 27 is temporarily stopped, and the suspension height of the core upper mechanism 21 by the hoisting mechanism 27 is adjusted so that the core upper mechanism 21 becomes horizontal. It may be a method of adjustment.

Further, these embodiments can be implemented in various other forms, in the case where the load meter detects an abnormal value in which the lifting load of the heavy object exceeds a preset threshold value when the heavy object is lifted. , The controller may issue a command to the hydraulic pump for a predetermined time to switch the operation of the hydraulic cylinder 9 to the hanging side of a heavy object.

Further, three hoisting mechanisms 27 are installed at intervals of 120 ° in a plane viewed from the upper part of FIG. 3 downward, that is, in a plan view (viewed from the upper part in a plane). When hung with, stable support is possible, and there is an advantage that the variation in load is reduced. Further, since the tilt control of the three hoisting mechanisms 27 is performed, the linear tilt control is possible and the level of the heavy object can be maintained.

Further, the controller 11 may be configured to have an interlock that calculates the tilt angle based on the tilt of the inclinometer 10 in two directions of XY and prohibits the operation of the hoisting mechanism 27 in the direction in which the tilt increases. It is possible.

Although some embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. Of course, these embodiments can be implemented in various other forms, and various omissions, replacements, modifications, and changes can be made without departing from the gist of the invention.

For example, in the embodiment of FIG. 2, the inclination is detected in two directions of XY, but the inclination may be detected in three directions by using the Z direction perpendicular to the X direction and the Y direction, respectively. Then, the inclination may be measured using two of these three directions other than the XY direction already described.

Further, although the controller 11 is arranged separately from the controller 3 in some embodiments, it is needless to say that the controller 11 may be integrally configured in the controller 3.

In addition, not only when the heavy object is stored separately in the storage container, but also when the heavy object is lifted and hung in a space that obstructs the surroundings, the point is that the heavy object does not come into contact with other members. In other words, it relates to a method of suspending and suspending the surrounding environment so as not to interfere with or interfere with the surrounding environment.

As described above, these embodiments and modifications thereof are included in the scope of the invention described in the claims and the equivalent scope thereof, as are included in the scope and gist of the invention.

1: Hydraulic jack 2: Hydraulic pump 3: Controller 4: Operation panel 5: Load meter 6: Upper grip mechanism 7: Lower grip mechanism 8: Rope 9: Hydraulic cylinder 10: Incline meter 11: Controller 12, 13: Grip 21: Measurement plug 22: Shielding floor 23: Work floor 24: Cask 25: Hanging bracket 26: Lifting stand 27: Hoisting mechanism 28: Rope 29: Hydraulic jack

Claims (5)

In a method of lifting and lowering a heavy object by controlling a plurality of hoisting mechanisms equipped with a hydraulic jack operated by a hydraulic pump by a controller.
The heavy object is an internal structure in a nuclear power plant.
When the lifting load of the heavy object by the hydraulic jack is measured by a load meter and the load meter detects an abnormal value in which the lifting load of the heavy object exceeds a preset threshold value when the heavy object is lifted. , The controller issues a command to stop lifting the heavy object to the hydraulic pump, and on the other hand, when the heavy object is suspended, an abnormal value in which the suspension load of the heavy object is less than a preset threshold value is measured by the load meter. There when detecting a predetermined time an instruction to switch to the lifting side of the heavy to the hydraulic pump from the controller, and outgoing, the predetermined time after the command to switch on the lifting side is issued, the heavy wherein the time der Rukoto until just before the lifted, lifting heavy and hanging down method. The tilt angle of the heavy object is detected by an inclinometer, and when the tilt angle of the heavy object exceeds a preset limit value threshold value, the operation of the hoisting mechanism is temporarily stopped to temporarily stop the operation of the heavy object. The method for lifting and lowering a heavy object according to claim 1, wherein the inclination angle of the above is adjusted horizontally. The method for lifting and lowering a heavy object according to claim 1 or 2, wherein the load cell is a load cell. The method for lifting and lowering a heavy object according to any one of claims 1 to 3, wherein three hoisting mechanisms are installed at intervals of 120 ° in a plan view. The threshold value is a load value that exceeds the limit value of the lifting load when the heavy object is lifted, and is a load value that is less than the limit value of the hanging load when the heavy object is lifted. The method for lifting and lowering a heavy object according to any one of claims 1 to 4 , wherein the load value is such that the heavy object is damaged.

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