JP4970832B2 - Elevator for reactor equipment - Google Patents

Description

  The present invention relates to an elevating device for in-reactor equipment for taking out and assembling an in-reactor structure in a reactor pressure vessel from a nuclear pressure vessel.

  A reactor pressure vessel is stored in the nuclear reactor building. The nuclear pressure vessel is equipped with a steam separator and a steam dryer from the position close to the core above the core as a reactor internal structure.

  Cooling water heated in the reactor core becomes a gas-liquid two-phase flow and flows into the steam-water separator, where it undergoes gas-liquid separation and the steam flows into the steam dryer. It is sent to an outdoor steam turbine generator and converted to electrical energy.

  In the periodic inspection of this nuclear power plant, when the fuel constituting the core in the reactor pressure vessel is replaced or the core is inspected, the steam dryer or steam separator located above the core is installed. Must be removed.

  Conventionally, the lifting and moving of the steam dryer and steam separator has been performed only on the crane hook of the overhead crane with the suspension wire and the cross beam beam suspension so that the crane hook of the overhead crane is not immersed in water. The water level of the reactor well was also raised and lowered as the crane hook of the overhead crane moved up and down.

  This is to prevent contamination of the crane hook with the reactor water. In order to improve these points, devices that can be used even when the reactor well is full have been made in recent years.However, when the reactor well is full, it is easily affected by the flow of water, and the steam separator and steam dryer are being lifted. Shaking occurred and the operator had to stop the lifting work while visually checking.

JP-A-9-304578

  While the crane hook of the overhead crane is stopped at a position where it is not immersed in water, the work of lifting and moving the steam dryer and the steam / water separator is performed with a chain block provided between the lifting tool and the crane hook.

  In this case, it is necessary for the worker to always have no visual confirmation, and the worker must recognize the abnormal state during the lifting and stop the lifting, which places a heavy burden on the worker and is liable to cause human error. .

  In view of the above problems, the present invention aims to provide an apparatus for raising and lowering equipment in a reactor that can safely suspend and move equipment such as a steam dryer and a steam separator even when the reactor well is full of water. To do.

  The present invention relates to a lifting device for an in-reactor device having an overhead crane, a crane hook hanging from the ceiling, and a hoisting machine suspended from the crane hook, wherein the hoisting machine includes a plurality of hoisting motors. And an encoder for detecting the rotation of the plurality of hoisting motors, and having a control means for measuring the detected value of the encoder and stopping or continuing the operation of the hoisting machine. And

  Further, the present invention provides an elevator apparatus for an in-reactor device having an overhead crane, a crane hook suspended from the ceiling, and a hoisting machine suspended from the crane hook, wherein the hoisting machine includes a plurality of hoisting machines. A plurality of hoisting wires such as wires and chains wound around a winding drum driven by each hoisting motor, and the plurality of hoisting motors balance the winding of the hoisting cords on the winding drums. The rotation is controlled so that the winding machine is kept, and a limit switch is provided to stop the operation of the hoisting machine when the balance between the windings is lost.

  According to the present invention, when the equipment is moved up and down, the operation is stopped by detecting the rotation of a plurality of hoisting motors with the encoder, or when the balance of the winding of the suspension rope is lost, the limit switch is operated to stop the operation. So it is safe.

  Thereby, it is possible to move the steam dryer and the steam / water separator without immersing the hook of the overhead crane in the water and without adjusting the water level of the reactor well, and it is possible to work without burdening the operator.

  Since such safety measures are established, human error prevention can be realized.

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

  In the reactor building in the nuclear power plant, a reactor well D, a dryer, and a separator pool B connected by a water channel A as shown in FIG.

  A weir F is provided at the bottom of the water channel A.

  Above the work floor E of the reactor building, an overhead crane 4 that is movable between the reactor well D and the dryer / separator pool B is installed, and the crane hook 5 of the overhead crane 4 extends to below the reactor well D. Accessible.

  The reactor pressure vessel C is located below the reactor well D.

  Inside the reactor pressure vessel C, a steam dryer 1 and a steam / water separator 2 are arranged from above.

  FIG. 2 shows the structure of the steam dryer 1, and a suspension fitting 3 is attached to the outer periphery of the steam dryer 1 at a position 90 ° above, and a hole 3 a is formed in the suspension fitting 3 in the radial direction. ing.

  The hole 3a of the hanging metal fitting 3 is used for lifting the steam dryer 1 itself.

  FIG. 3 shows the structure of the steam / water separator 2, and a suspension fitting 6 is attached to the outer periphery of the steam / water separator at a position 90 ° above, and a hole 6 a is formed in the suspension fitting 6 in the radial direction. It has been.

  The hole 6a of the hanging metal fitting 6 is used for lifting the steam / water separator 2 itself.

  As shown in FIG. 4, the lifting device for the in-reactor equipment is arranged such that the upper block 8 of the hoisting machine 7 that engages with the crane hook 5 and the hook pin 9 for connecting the upper block 8 and the crane hook at the top. Has been.

  The upper block 8 includes a winding drum 21 that winds / feeds the chain (suspending rope) 20, four winding motors 22 that rotationally drive the four winding drums 21, and each winding motor 22. An encoder 23 for detecting rotation is directly connected. The chain (suspending rope) 20 is wound around the left and right winding drums 21 through an upper sheave 24 (upper pulley) and a lower sheave 25 (lower pulley).

  In other words, the chain (suspending rope) 20 is stretched over a plurality of upper sheaves 24 (upper pulleys) and a plurality of lower sheaves 25 (lower pulleys), and both ends are wound around the right and left winding drums 21. is there.

  Plural (three) upper sheaves 24 (upper pulleys) are attached to the lower side of the upper block 8, and plural (four) lower sheaves 25 (lower pulleys) are attached to the lower block 26. In conjunction with the winding / winding of the chain (suspending cord) 20, the upper sheave 24 (upper pulley) and the lower sheave 25 (lower pulley) rotate, and the lower block 26 also moves up and down.

  FIG. 5 and FIG. 7 show the state where the chain (hanging rope) 20 is wound up / down.

  A striker 27 that is thicker than the chain is attached to the left and right chains 20 that pass through the upper sheave 24 at the center of the upper block 8. The striker (striking body) 27 has a structure capable of hitting a limit switch 28 attached to the lower end of the upper block 8.

  An upper balance 40 is provided below the lower block 26, and these are coupled by a connecting pin 41, and the connecting pin 41 can be removed to be separated from the upper balance 40.

  The upper balance 40 has a cross beam structure. A suspension wire 42 is attached to the tip of each beam of the upper balance 40, and a suspension base 43 having a cross beam structure larger than that of the upper balance 40 is connected to the lower end of the suspension wire 42.

  The suspension wire 42 and the upper balance 40 and the suspension wire 42 and the suspension base 43 are connected by wire pins.

  An air cylinder 45 and a pin 46 that is driven by the air cylinder 45 are attached to the beam 44 extending in all directions of the suspension base 43, and a pin box 47 that supports driving of the pin 46 is attached. Since the pin 46 is slidably supported by the pin box 47, the pin 46 is smoothly driven by the air cylinder 45.

  As described above, the suspension fitting 3 is attached to the outer periphery of the steam dryer 1 at a position 90 ° above, and the suspension fitting 3 is provided with a hole 3a in the radial direction.

  The hole 3a of the hanging metal fitting 3 is used for lifting the steam dryer 1 itself.

  FIG. 3 shows the structure of the steam / water separator 2, and a suspension fitting 6 is attached to the outer periphery of the steam / water separator at a position 90 ° above, and a hole 6 a is formed in the suspension fitting 6 in the radial direction. It has been.

  The hole 6a of the hanging metal fitting 6 is used for lifting the steam / water separator 2 itself.

  This pin 46 is smaller than the hole diameter of the suspension fitting 3 of the steam dryer 1 shown in FIG. 2 or the suspension fitting 6 of the steam / water separator 2 shown in FIG. 3, and the insertion and withdrawal of the pin 46 is possible in both holes 3a and 6a. It has a structure that can be done.

  The pin box 47 has a hole that matches the diameter of the pin 46 and has a box-type structure so that a vertical load applied to the pin 46 can be received.

  The air cylinder 45 for driving the pin 46 is constituted by a system of an air operating device as shown in FIG. 6, and by operating the switching valve 49 of the operation box 48, the pin 46 is inserted (a) and pulled out (b). Is done.

  The operation box 48 and the air cylinder 45 are connected by using a hose 60 and a connection joint 61 so that air can be supplied to the air cylinder 45 even remotely.

  The structure of the lifting device is as described above. However, when the lifting device is moved in a state where the nuclear reactor is full, the lifting device is easily affected by water, and the chain (suspending rope) 20 is being wound / winded up. In addition, due to the large shaking of the device itself, the winding (winding) of the chain 20 may not be successful.

  The water in the reactor well D, the dryer, and the separator pool B is always circulated by a pump. This water circulation also affects the winding / winding of the chain (suspending rope) 20.

  These situations can lead to major accidents if they occur when a steam separator or steam dryer is suspended. Accordingly, it is necessary to always monitor whether the chain (suspending cord) 20 is normally wound / wound, and if it is not normal, it is necessary to stop the apparatus.

  For this purpose, in this apparatus, the number of rotations of the hoisting motor 22 is detected by the four encoders 23, the winding / winding amount is calculated from the detected value, and whether the calculated value is always the same value. Monitoring.

  For example, when the difference between the maximum value and the minimum value of the four calculated values becomes larger than a specified value, the winding / feeding of the chain (hanging rope) 20 is stopped. In addition to using the difference between the maximum value and the minimum value described here as the determination value, the variation of the four calculated values can also be used for the determination.

  Control based on the detection value data of the encoder 23 is provided with control means for stopping and continuing the operation of the hoisting motor 22 and adjusting the speed.

  Furthermore, when the encoder 23 breaks down or when the winding (winding rope) 20 of the chain (suspending rope) 20 on the winding drum 21 is disturbed, monitoring by the encoder 62 is not sufficient, so that further safety is achieved. As a countermeasure backup function, a striker (striking body) 27 of the left and right chain (suspension rope) 20 passing through the upper sheave 24 (upper pulley) in the center of the upper block 8 and a limit switch 28 attached to the lower end of the upper block 8 are provided. Use.

  The striker (striking body) 27 is at a certain height when the winding (winding) of the chain (suspending rope) 20 is normal. That is, when normal, the winding (winding) of the chain (suspending rope) 20 is balanced. For this reason, the upper sheave 24 (upper pulley) at the center is in a stopped state.

  However, when an abnormality occurs in winding / feeding of the chain (suspending rope) 20 and the balance is lost, the upper sheave 24 (upper pulley) at the center rotates in one direction. That is, as shown in FIG. 7, unevenness occurs in the winding / winding speed of the left and right chains, and the height of the striker (striking body) 27 is different.

  At this time, one striker (striking body) 27 moves upward and hits the limit switch 28 to stop winding / unwinding of the chain (striking body) 27.

  FIG. 8 shows a flow of operation logic of the lifting device using the encoder 23 and the limit switch 28.

  A method of removing and attaching the steam dryer 1 and the steam / water separator 2 using the lifting device having the above-described operation logic will be described.

  A procedure for removing the steam dryer 1 by the lifting device will be described with reference to FIG.

  As shown in Step 1 of FIG. 9, the water in the reactor well D is full, and the dryer, separator pool B, and water channel A are at the same water level as in the reactor well D.

  The upper block 8 to the lower block 26 of the lifting device are already assembled and temporarily placed on the mount 7 on the work floor E. The suspension wire 42 and the suspension base 43 are temporarily placed on the work floor E.

  Next, as shown in Step 2 of FIG. 9, after connecting the crane hook 5 and the upper block 8, the crane hook 5 is raised and the upper balance 40 is suspended from the lower block 26. Further, by attaching the suspension wire 42 and the suspension base 43 under the upper balance 40 and further configuring the air operating device of the lifting device shown in FIG. 6, the assembly of the lifting device shown in FIG. 4 is completed.

  Next, as shown in Step 3 of FIG. 9, the crane hook 5 is moved into the reactor well D and stopped at a position above the center of the reactor pressure vessel C.

  Next, as shown in Step 4 of FIG. 9, by lowering the crane hook 5 from this position, the lower part including the lower block 26 is immersed in the water in the reactor well D, and the lower end of the crane hook 5 is the water surface. The crane hook 5 stops descending when it reaches a position of about 2 to 3 m from the distance.

  In this state, the upper block 8 and the crane hook 5 are in the air. That is, the reactor well D is not immersed in water.

  With the crane hook 5 stopped at this position, the chain (suspension cable) to a level at which the pin box 47 of the suspension base 43 engages with the suspension fitting 3 of the steam dryer 1, that is, the level at which the suspension base 43 sits on the suspension fitting 3. 20 rolls down.

  After the seating, the steam dryer 1 is gripped by remote control using the air operating device shown in FIG.

  The water level in the reactor well D is not adjusted while the reactor well D is fully filled between the time when the descending of the crane hook 5 is stopped and the time when the steam dryer 1 is gripped. Do not immerse 5 in contaminated water.

  Next, as shown in Step 5 of FIG. 9, the chain (suspending rope) 20 is wound up and the steam dryer 1 is pulled up. During the winding, the monitoring and emergency stop functions using the encoder 23 and the limit switch 28 are always used in consideration of the influence of the water flow.

  Next, as shown in Step 6 of FIG. 9, the chain (1) is connected to a position where the lowest end of the steam dryer 1 is higher than the weir F of the water channel A and the upper portion of the steam dryer 1 is below the water surface of the reactor well D. Hoist 20) is wound up.

  The steam dryer 1 pulled up to this height is sufficiently immersed in water because the reactor well D is full, and the radiation of the steam dryer 1 is kept shielded by water.

  In Step 5 of FIG. 9, the hoisting machine 7 (chain block) is wound up and then the crane hook 5 is lifted in Step 6. However, the crane hook 5 is lifted first, and then the hoisting is performed. The procedure may be to wind up the machine 7 (chain block).

  Next, as shown in step 7 of FIG. 9, the crane hook 5 is moved in parallel to the storage position of the dryer and separator pool B.

  Finally, as shown in Step 8 of FIG. 9, the steam dryer 1 is suspended by the hoisting machine 7 (chain block) until the steam dryer 1 is seated on the floor of the dryer / separator pool B.

  After the seating, the lifting device is separated from the steam dryer 1 using the air operating device shown in FIG.

  The elevating device in an empty state is then used to remove the steam / water separator 2.

  The removal procedure of the steam separator 2 by the lifting device will be described with reference to FIG.

  As shown in the step of FIG. 10, the crane hook 5 is moved into the reactor well D and stopped at a position above the center of the reactor pressure vessel C.

  Next, as shown in Step 2 of FIG. 10, by lowering the crane hook 5, the area below the lower block 26 is immersed in the water in the reactor well D, and the lower end of the crane hook 5 is about 2 to 3 m from the water surface. When the position is reached, the lowering of the crane hook 5 is stopped.

  In this state, the crane hook 5 and the upper block 8 are in the air, that is, not immersed in the water of the reactor well D.

  While the crane hook 5 is stopped at this position, the hoisting machine 7 is moved to a position where the pin box 47 of the suspension base 43 is engaged with the suspension fitting 6 of the air / water separator 2, that is, a position where the suspension base 43 is seated on the suspension fitting 6. Simultaneously lower the (chain block).

  After sitting, the air / water separator 2 is gripped by remote control using the air operating device shown in FIG.

  The water level in the reactor well D is not adjusted while the reactor well D is in a fully filled state after the descent of the crane hook 5 is stopped until the steam-water separator 2 is gripped. Do not immerse 5 in contaminated water.

  As shown in Step 3 of FIG. 10, the chain (suspending rope) 20 is wound up and the steam / water separator 2 is lifted. During this winding, the monitoring and emergency stop functions using the encoder 62 and limit switch 63 are always used in consideration of the influence of the water flow.

  As shown in Step 4 of FIG. 10, the crane hook 5 reaches a position where the lowermost end of the steam separator 2 is higher than the weir F of the water channel A and the upper portion of the steam dryer 2 is below the water surface of the reactor well D. To raise.

  The steam-water separator 2 pulled up to this height is sufficiently immersed in water because the reactor well D is full, and the radiation of the steam-water separator 2 is kept shielded by water.

  In the step of FIG. 10, the hoisting machine 7 (chain block) is hoisted and then the crane hook 5 is raised at the step. However, the crane hook 5 is raised first, and then the hoisting machine 7 is raised. The procedure may be to wind up the machine 7 (chain block).

  Next, as shown in step 5 of FIG. 10, the crane hook 5 is moved in parallel to the storage position of the dryer and separator pool B.

  Next, as shown in Step 6 of FIG. 10, the steam-water separator 2 is suspended until the steam-water separator 2 is seated on the floor of the dryer / separator pool.

  The crane hook 5 may be lowered and seated.

  After completion of the suspension, the air operating device shown in FIG. 5 is used to disconnect the lifting device from the steam separator 2 and the chain (suspending rope) 20 is wound up.

  Next, as shown in Step 7 of FIG. 10, after the removal of the steam / water separator 2 is completed, the crane hook 5 is raised and the suspension base 43 is pulled up onto the work floor E.

  Finally, as shown in Step 8 of FIG. 10, the hanging wire and the hanging tool are removed from the underwater moving device on the work floor E, and the rest of the underwater moving device is temporarily placed on the pedestal on the work floor E, and the crane hook 5 The hook pin 9 connecting the upper block 8 and the upper block 8 is extracted, and the crane hook 5 and the lifting device are separated.

  When the steam dryer 1 and the steam / water separator 2 were moved from the dryer / separator pool B to the reactor pressure vessel C and installed in the reactor pressure vessel C, the reactor well B was similarly filled with water. The work can be performed in the reverse procedure of FIGS. 9 and 10 in the state.

  The present invention is applicable to the handling of steam dryers / water separators at nuclear power plants, but can also be applied to other industrial fields that require suspension work in water.

It concerns on the Example of this invention, and is the top view (a) and sectional drawing (b) of a reactor building. It concerns on the Example of this invention, and is the top view (a) and sectional drawing (b) of a steam dryer. It concerns on the Example of this invention, and is the top view (a) and side view (b) of a steam-water separator. FIG. 4 is a top view (a), a front view (b), a side view (c), and a plan view (d) of a lifting device according to an embodiment of the present invention. FIG. 4 is a diagram (a) showing a chain driving state when the hoisting machine is suspended and a diagram (b) showing a chain driving state when the hoisting machine is suspended, according to the embodiment of the present invention. FIG. 5 is a system diagram of an air operating device of a lifting device according to an embodiment of the present invention. It is a figure which concerns on the Example of this invention and is a figure explaining operation | movement of the limit switch of a winding machine. It is a figure which concerns on the Example of this invention, and is a figure which shows the operation | movement flow of an encoder or a limit switch. It is a figure which concerns on the Example of this invention, and shows the removal step of a steam dryer. It is a figure concerning the Example of this invention, and is a figure which shows the removal step of a steam-water separator.

Explanation of symbols

  4 ... overhead crane, 5 ... crane hook, 7 ... hoisting machine, 8 ... upper block, 26 ... lower block, 22 ... hoisting motor, 21 ... winding drum, 24 ... upper pulley, 25 ... lower pulley, 20 ... Hanging rope, 23 ... encoder.

Claims (3)

In an elevating apparatus for in-reactor equipment having an overhead crane, a crane hook hanging from the ceiling, and a hoisting machine suspended from the crane hook,
The hoisting machine is driven by an upper block suspended from the crane hook, a lower block suspended from the upper block, at least two hoisting motors provided on the upper block, and the two hoisting motors. Winding drum, a plurality of upper pulleys provided on the upper block, a plurality of lower pulleys provided on the lower block, the lower pulley and the upper pulley, and the end side is wound on the winding drum. and a hanging rope,
The suspension rope that passes through the upper pulley at the center of the upper block and falls to the left and right sides of the upper pulley has a striker that is thicker than the suspension rope,
The upper block has a limit switch that stops operation of the hoisting machine when a balance between the windings wound around the two hoisting motors is lost.
The apparatus for raising and lowering the in-reactor equipment, wherein the striker moves up and down by the rotation of the upper pulley at the center as the balance is lost, and the limit switch is operated. In the apparatus for raising and lowering reactor equipment according to claim 1,
An encoder for detecting rotation of the plurality of hoisting motors;
And a control means for measuring the detection value of the encoder and stopping or continuing the operation of the hoisting machine. In the apparatus for raising and lowering reactor equipment according to claim 1,
An upper balance suspended from the lower block, a suspension base suspended from the upper balance via a suspension wire, an air cylinder provided on the suspension base, a pin box provided on the suspension base, and a pin box An apparatus for raising and lowering equipment in a nuclear reactor, which is slidably supported and has a pin for gripping or releasing equipment in the nuclear reactor by operating the air cylinder.

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