JPS6112560B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a decontamination device, and particularly to a device for decontaminating parts of a nuclear power plant.

During the operation of nuclear power plants and similar equipment, certain components are exposed to radiation and a thin film of radioactivity develops on the surface of the component. Over time, the need arises to inspect and repair these parts of the nuclear plant. During inspection or repair of the part, workers may be exposed to radiation from the contaminated part because they are required to enter or be in close proximity to the part. In some cases, the radiation field emanating from this component is such that workers receive the maximum permissible radiation dose in less than 5 minutes of working time. In this case, the time available for workers to perform inspection or repair work on nuclear power plants will be relatively short.
The limited amount of time available for each worker to perform repair or inspection tasks may result in the need to use a large number of workers, as each worker can work only a short amount of time to complete the required work. This is acceptable for small inspections or repair work, but is not acceptable when large-scale inspections or repairs are required. If the required work is time-consuming, it will likely require an unusually large number of highly trained people to complete the job. Such a situation is unacceptable both from a financial standpoint and from the perspective of the number of people required. Therefore, it is necessary to use decontamination equipment to reduce the radiation field of nuclear plant parts and allow workers to complete their work on the parts.

JP-A-56-24599 describes a device in which parts to be decontaminated are sprayed with a mixture of water and sand at a distance, for example with a nozzle depending from a tube plate of a steam generator. However, the mounting position and tangential velocity of the nozzle with respect to the surface of the part to be decontaminated should be such that the force of the water and sand mixture is sufficient to adequately clean and decontaminate, but not so much as to damage the surface of the part. must be controlled. If the nozzle speed is too high and/or too far from the surface of the part to be decontaminated, both cleaning and decontamination will be inadequate. Also, damage to the surface of the part to be decontaminated is caused by the nozzle speed being too low or by the nozzle being too close to the surface of the part to be decontaminated.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a control device for controlling the movement of a control arm having a nozzle device such that the above-mentioned disadvantages do not occur.

To this end, according to the invention, a pivot end is connected to a pivot device inside a spherical enclosure of a steam generator having a center and is fixed in a predetermined position at a first predetermined distance from said center of said enclosure; a control arm having a nozzle arrangement for directing abrasive mixture toward a surface of the enclosure to remove radioactive contaminants from the surface, the control arm having a change in linear radius from the pivot end; said nozzle device being slidably mounted thereon and said control arm movable about said pivot device such that there is a controlled change in horizontal and vertical angular position and angular velocity; a tangential velocity device that generates a first set point signal proportional to a predetermined tangential velocity as the nozzle device moves relative to the surface of the enclosure; a first feedback signal generator for generating a first feedback signal proportional to the linear radius of the control arm; a second feedback signal generator for generating a second feedback signal proportional to the actual angular position of the control arm; a third feedback signal generator for generating a third feedback signal proportional to the effective radius of the nozzle device in response to the first and second feedback signals; a second set point signal generating device responsive to the second set point signal for generating a second set point proportional to the angular velocity required to move the nozzle arrangement at the predetermined tangential velocity; a drive device for angularly moving the control arm about the pivot device at the angular velocity; and an adjustment device for adjusting the radius to permit substantially uniform cleaning of the surface.

The control device includes a device for controlling the nozzle velocity to maintain a predetermined magnitude of the tangential velocity of the nozzle, ie, the velocity of the nozzle with respect to the inner surface. The predetermined tangential velocity described above is sufficiently large that the surface to be cleaned is not damaged by prolonged exposure to the water and sand abrasive mixture, yet long enough to provide adequate cleaning. within a selected speed range that is small enough to expose the
The control system includes a device for adjusting the distance between the nozzle and the pivot device by means of certain command signals.

In one mode of operation, called ball cleaning mode, this adjustment device operates to maintain a predetermined distance between the spherical center of the inlet or outlet chamber and the nozzle. In two other operating modes, called the partition plate cleaning mode and the tubesheet cleaning mode, the adjustment device operates to periodically adjust the distance between the center of the sphere and the nozzle by fixed incremental distances.

In the ball cleaning mode, the predetermined distance described above is such that the distance between the surface to be cleaned and the nozzle is large enough so that the pressure from the water and sand mixture applied by the nozzle is not excessive and damages the surface; within a range of distances that are sufficiently small to ensure that the surface is subjected to pressure of sufficient strength to properly clean or decontaminate the surface. Similarly, in the tubesheet cleaning mode and the divider cleaning mode, the nozzle is maintained at a distance within a distance range that adequately cleans the surface to be cleaned, but does not damage it.

The invention will become more readily apparent from the following description of preferred embodiments thereof, taken in conjunction with the accompanying drawings.

FIG. 1 shows a primary inlet chamber or plenum 10 of a nuclear steam generator (not shown) having a generally spherical shape. The inlet chamber 10 is characterized by a center 11, a curved enclosure or inner surface (ball-shaped surface) 12, a partition plate 14 and its surface, and a tube plate 16 and its surface.
As will be understood by those skilled in the art, the tubesheet 16 is generally cylindrical and has lumens into which the fluid flow tube bundles are fitted. The partition plate 14 defines a primary inlet chamber and an outlet chamber of a nuclear steam generator (not shown), but only the primary inlet chamber 10 is shown in FIG.

The device for cleaning surfaces 12, 14, 16 has a control arm 18 mounted on a pivot device 20 inside the inlet chamber 10, the pivot device 20 being connected to a support device 2.
2 on the tube plate 16. The illustrated embodiment of control arm 18 includes a support arm 24 extending directly from pivot device 20. The nozzle support conveyor 26 is connected to the support arm 2
4 is slidably mounted. A carriage stop 28 is mounted on the support arm 24 near the pivoting apparatus 20 to prevent the supporting carriage 26 from getting too close to the pivoting apparatus 20. Nozzle extension arm 3
0 has a nozzle end 31 and is slidably mounted on a support carriage 36. Nozzle device 32 and flexible tube 3
4 is used to clean the surface to be cleaned, namely 12, 1.
The nozzle extension arm 30 is provided for cleaning the surfaces surrounding the inlet chamber 10 by applying a water and sand mixture under constant pressure to the nozzle extension arm 30 . The flexible tube 34 serves as a device for guiding the water and sand mixture from the source to the nozzle arrangement.

In order to describe the manipulator or control device of the invention and its operation, the distance from the center 11 of the sphere to the attachment point 21 of the support device 22, the attachment point 21
The distance from This is an important distance.

In order to clarify the important relationships, the control device of FIG. 1 is shown geometrically in FIG. As shown in FIG. 2, the following variables are defined.

a = pivot device 20 from center 11 of entrance chamber 10
vertical distance to the center of

b = pivot device 20 from center 11 of entrance chamber 10
horizontal distance c to the center of the control arm 18 = vertical distance from the center line of the control arm 18 to the nozzle end 31 r' = linear radius of the nozzle end 31 with respect to the pivot device 20, i.e. the straight line distance between the two r = from the control arm 18 to the nozzle end 31 Distance R from the pivoting device 20 to the vertical line projected on the surface R = Fixed distance θ between the center 11 of the inlet chamber 10 and the nozzle end 31 in the ball surface cleaning mode = Angle of horizontal movement of the control arm 18 (second (In the case of the figure, it moves in and out of the paper) φ = Angle of vertical movement of the control arm 18 (in the case of Fig. 2, on the paper) r'cogφ = Effective radius of the nozzle end 31 The most important variables r and r' The trigonometric equation for calculating cosφ is as follows.

r=-B+√ ² + ^2Here , B=a sinφ+b cosφsinθ C=R ² −a ² −b ₂ −c ² −2c [−a cosφ+bsinφsinθ] r′cosφ=√ ² + ² (cosφ) Fig. 3 controls the speed and direction of movement of control rod 18 about pivot device 20 via control signal 51 and controls the nozzle support on control arm 18 via control signal 39 responsive to start signals 61, 62. A manipulator 35 provided for adjusting the position of the carrier 26 is shown.

As shown in FIG. 3, the manipulator 35 includes a carrier feedback signal control device in a line indicated by the reference numeral 36 in order to adjust the position of the nozzle support carrier 26, and also controls around the pivot device 20. In order to control the speed and direction of movement of arm 18, a control arm feedback signal controller is included in line 38. start signal 61,
Reference numeral 62 is provided only for initiating movement of the carriage 26 and the control arm 18.

Once the movement is initiated by the start signals 61, 62, the direction, speed and amount of movement are as predetermined by parameters in the control arm feedback signal controller 38 and the carriage feedback controller 36. It becomes. The carriage feedback controller 36 and the control arm feedback controller 38 are suitably activated by start signals 61, 62 to regularly clean any of the three surfaces surrounding the primary inlet chamber 10, i.e. surfaces 12, 14, 16, i.e. Decontaminate.

A carriage feedback controller 36 controls the nozzle support carriage 2 on the support arm 24 so that the nozzle arrangement 32 is positioned neither too close nor too far from the ball-shaped surface 12.
In order to adjust the position of the nozzle support conveyor 26
and a carriage positioning motor 40 suitably provided therein. If the adjustment of the motor 40 brings the nozzle device 32 too close to the ball-shaped surface 12, the ball-shaped surface 12 will be exposed to excessive pressure from the water and sand mixture.
The surface 12 may be damaged as it is exposed. Conversely, if the nozzle arrangement is moved too far from the ball-shaped surface 12 by adjusting the motor 40, the water and sand mixture may not be able to apply sufficient pressure to the surface 12 to clean the surface 12. I don't know. Position controller 41 responds to feedback signal 42 from motor 40 and start signal 61 to provide control signals 43 that control the speed and direction of movement of motor 40.

A control arm feedback controller 38 is suitably mounted in connection with the pivot device 20 and includes a motor control 50 that provides an output signal 51 that controls the speed and direction of pivoting of the control arm 18 about the pivot device 20. include. In particular, the pivoting of control arm 18 is assumed to occur at an angle θ in the horizontal plane and φ in the vertical plane. Position control control device 52 and speed control device 53
in response to the feedback signal 54 from the output of the motor device 50 and the start signal 62, respectively, provide a position control signal 55 and a speed control signal 56 for controlling the speed and direction of movement of the motor device 50, respectively. put out. The speed control device 53 is important in controlling the angular velocity of the control arm 18 so that the range of angular velocity is neither too fast nor too slow. It is known that if the angular velocity is too low, the surfaces to be cleaned, ie surfaces 12, 14, 16, may be damaged by the high pressure from the water and sand mixture. Conversely, if the angular velocity is too high and the surface 12 does not receive sufficient pressure from the water and sand mixture, adequate cleaning of the surface 12 will not be possible.

The start control 60 generates start signals 61, 6 at approximately the same time.
Roll 2. The start control is performed by starting signals 61, 6.
A control console or panel may be provided that has controls for manually issuing 2, such as a control that is manually adjusted by an operator. Further, the start control 60 may be configured by using a signal generator instead of or in addition to the signal generator described above.
For example, a control may be provided to automatically generate the start signals 61, 62, such as a microprocessor programmed with instructions to generate the start signals 61, 62 in the appropriate order.

The initiation control 60 operates, either manually or automatically, for at least three times, one for each of the surfaces to be cleaned, namely the surface of the partition plate 14, the surface of the ball-like surface 12, and the surface of the tubesheet 16. Provides two possible modes of cleaning work. The first working mode is called the ball cleaning mode, in which the nozzle device 32 travels along a horizontal path and a vertical path to clean the ball-shaped surface 12. The second operating mode is referred to as the tubesheet cleaning mode, in which the control arm 18 is positioned horizontally and the nozzle device 32 is directed upwardly to apply a water and sand mixture to the tubesheet surface 16. control arm 1
8 runs horizontally around the pivot device 20, and the support carriage 26 is moved incrementally along the control arm 18 to fully expose the tubesheet surface 16 to the water and sand mixture. In a third working mode, called the partition cleaning mode, the control arm 18 is fixed in position at the end of the horizontal corner such that the nozzle device 32 is close to and directed towards the partition surface 14. In order to completely expose the partition surface 14 to the water and sand mixture, the control arm 18 travels through a vertical corner and the support carriage 26 is adjusted incrementally along the entire length of the support arm 18. . The starting device 60 may include a device for automatically or manually selecting one of three working modes: a partition plate cleaning mode, a tubesheet cleaning mode, and a ball cleaning mode. A manually operated switch may be provided to allow manual control of the movement sequence of the control arm 18 and support carriage 26 by an operator, or an automatic sequence may be performed by a microprocessor containing appropriate instructions. .

FIG. 4 shows that the carriage feedback control device 36 of FIG.
8, a function generator 69, and a setpoint module 70. Proportional feedback controller 68 provides a control signal 39 to control arm 18 and provides an output signal 74 to function generator 69 in response to output signal 75 from setpoint module 70. FIG. 4 also shows that the control arm feedback controller 38 of FIG. 3 includes proportional feedback controllers 77, 78, a function generator 9, and a setpoint module 70. Proportional feedback controller 77 provides a horizontal position signal 82 to function generator 69 in response to output signal 75 to control the rate of movement of control arm 18 in the horizontal direction. axis) outputs a control signal 80. Proportional feedback controller 78 controls control arm 18 in the vertical direction.
In response to the output signal 75, a vertical position signal 84 is provided to the function generator 69 and a vertical (theta axis) control signal 86 is provided to the control arm 18 in order to control the speed of movement of the control arm 18. Function generator 69 provides an output signal 88 to setpoint module 70 that is proportional to the calculated commanded position of nozzle end 31.

FIG. 5 shows the manipulator 35 of FIG. 4 in more detail. In FIG. 5, the motor device 50 of FIG.
includes horizontal and vertical pivot motors 91 and 92. Detectors 93 and 94 are provided to detect the horizontal angular velocity and horizontal angular position of the horizontal pivot motor 91, respectively, and also detect the vertical angle (φ) of the vertical pivot motor 92.
Detection devices 95 and 96 are provided to detect velocity and vertical angular position (φ), respectively. The angular velocity detection device 93 is, for example, a device that measures the back electromotive force of the horizontal pivot motor 91, and the angular velocity detection device 95 can be, for example, a tachometer. A device including a partial pressure gauge 97 is provided to detect the linear position of the carriage 26 on the support arm 24 as determined by the carriage positioning motor 40. The linear speed of the carriage positioning motor 40 is controlled from the outside.

In FIG. 6, the movement and movement speed of the horizontal pivot motor 91 are expressed by the horizontal sensing devices 93, 9.
4 and the horizontal position (θ) running or command signal 105
horizontal position (θ) control signal 101 of a horizontal proportional controller module 103 which is responsive to feedback from the angular velocity command signal 107 and The horizontal proportional controller module 103 associated with the horizontal pivot motor 91 essentially generates horizontal command signals, namely the angular velocity command signal 107 and the horizontal position (θ).
The movement of control arm 18 in the horizontal (θ) direction is controlled in response to command signal 105 . Detection device 93
The horizontal angular velocity feedback signal and horizontal angular position (φ) signal 82 from the horizontal pivot motor 91
The actual horizontal angular velocity and horizontal angular position (θ) of Horizontal proportional controller module 103 operates to adjust the horizontal angular velocity and horizontal angular position (θ) of horizontal pivot motor 91 to match the appropriate horizontal feedback and horizontal command signals to each other.

For example, the horizontal position (φ) command signal 105 sets the horizontal angular position (θ) of the horizontal pivot motor 91 to θ=
One state indicating a command such as 0° and θ=
It may be a step function signal in a ball cleaning mode and a tubesheet cleaning mode with another state indicating a command such as 180 degrees. The device for generating the horizontal position (θ) command signal 105 may be, for example, the device 16 for issuing a step function in response to the horizontal start signal 169 from the starting device 60.
Contains 1.

The vertical movement of vertical pivot motor 92 and its angular velocity are determined by vertical position control signal 111 of vertical proportional controller module 113 which is responsive to feedback from vertical sensing devices 95, 96 and vertical position command signal 115 and angular velocity command signal 107. controlled. A vertical proportional controller module 113 associated with the vertical pivot motor 92 controls movement of the control arm 18 in the vertical (φ) direction essentially in response to vertical command signals, angular velocity command signal 107 and vertical position (φ) command signal 115. control. The vertical angular velocity feedback signal 90 from the angular velocity sensing device (tachometer) 95 and the vertical angular position (φ) feedback signal 84 from the sensing device (partial pressure meter) 96 are the vertical angular velocity and vertical angular position (φ) of the vertical pivot motor 92. and give the actual display. Controller module 113 functions to adjust the vertical angular velocity and vertical angular position of vertical pivot motor 92 to match the appropriate vertical feedback and vertical angle command signals to each other.

For example, the vertical position command signal (φ) 115 indicates that the vertical angular position (φ) of the vertical pivot motor 92 is φ=
1 is a step function signal in a divider cleaning mode having one state representing a command such that the vertical angular position of the vertical pivot motor 92 is 0° and another state representing a command such that the vertical angular position of the vertical pivot motor 92 is φ = 180°; . Or vertical position (φ) command signal 11
5, for example, the vertical angular position (φ) of the vertical pivot motor 92 changes from φ=0° to φ in a constant predetermined angular increment.
9. A step signal in a bowl cleaning mode with multiple discrete increments of magnitude such as through a 90° path up to =90°. Apparatus for generating vertical angular position command signals 115 may include, for example, apparatus 163 for issuing step functions and for issuing staircass functions in response to vertical motion initiation signals 168 from initiation apparatus 60.

In FIG. 7, the linear motion of the carriage positioning motor 40 is determined by the feedback from a device (partial pressure meter 97) that detects the position of the carriage and the carriage command signal 1.
The carrier position control signal 121 of a proportional controller module 123 is responsive to inputs from 25. A proportional controller module 123 associated with carriage positioning motor 40 controls movement of support carriage 26 on support arm 24 essentially in response to carriage command signal 125 . The carriage position feedback signal, output signal 74 from pressure gauge 97, provides an indication of the actual position of carriage positioning motor 40. Controller module 123 is operative to adjust the position of carriage positioning motor 40 to bring the carriage position feedback signal and carriage command signal into agreement with each other.

As shown in FIG. 5, the radius calculation bus signal 137
is the relay device 1 responsive to the relay control signal 135
33. Radius calculation bus signal 137
is the carrier radius calculation signal 17 based on the position of the relay device 132 determined by the relay control signal 135.
3 or 174. The carriage radius calculation signal 174 used in the ball cleaning mode is proportional to the distance between the center 11 of the primary inlet chamber 10 and the nozzle device 32. The carriage radius calculation signal 143 is provided to generate a carriage radius calculation signal 174, and the appropriate carriage radius calculation signal 174.
It may include a partial pressure gauge that is properly adjusted to provide the

The carriage radius calculation signal 173 used in the tubesheet cleaning mode and the divider plate cleaning mode is proportional to a certain predetermined incremental distance that the nozzle support carriage 26 moves. In FIG. 8, the carriage radius calculation signal 141
includes an incremental device 184 that provides a predetermined distance of linear radial adjustment to the support carriage 26. Incremental adjustments are made by ramp generator 186. Feedback signal 1 from the output of ramp generator 186
A device 187 is included for adding or subtracting the output of ramp generator 186 from the constant increment obtained from increment device 184 in response to step 88 . The output of the adder or subtracter 187, called the "update" signal, is always equivalent to the output of the ramp generator 186 which "adds" or "subtracts" the constant increment provided by the incrementer 184. Fact, addition or subtraction device 1
The output of 87 is the current linear radius or position of carriage 26 on control arm 18 plus or minus a constant increment. Track/storage device 189 responds to the output from logic device 190 to ramp generator 18.
Drive 6.

During operation of carriage radius calculation device 141, linear motion start signal 170 from initiator 60 causes logic device 190 to issue an increment start signal to track/storage device 189, which causes track/storage device 189 to read its input. ``holds'' the ``update'' signal (the ``update'' signal is the output of the adder or subtracter 187). The "update" signal is also provided as an input to ramp generator 186. Ramp generator 186 operates to adjust the "up or down" of its output, or feedback signal 188, to match the output of track/storage device 189.

Ramp generator 186 outputs a signal to logic 19 to remove the incremental start signal in response to a match between its output and the output of track/storage device 189.
Give to 0. By removing the increment start signal from the input of the track/store 189, the track/store 189 adds a constant increment of the increment unit 184 to the output of the adder or subtracter 187, i.e. from the output of the ramp generator 186. “Track up” or “track down” what is added or subtracted. A switch device 191 is included for floating the input of the ramp generator 186 in response to removal of the incremental start signal, i.e., disconnecting the input of the ramp generator from the input of the track/storage device. .

In FIG. 9, microprocessor portion 147 generates carriage command signal 125. In FIG. In the ball cleaning mode, the relay device 133 causes the carriage radius calculation signal 174 to match the radius calculation bus signal 13.
7 to the microprocessor 147 in response to a relay control signal 135. In this mode, microprocessor 147 uses position feedback signals to adjust the position of support carriage 26 such that nozzle 32 is maintained at a distance R from the center of primary inlet chamber 10 in FIG. 82 and 84 and a radius calculation bus signal 137 to issue a carriage command signal 125. Microprocessor 147 receives as input position feedback signals 82 and 84 and radius calculation bus signal 137 and performs the trigonometric calculations shown in equation (1).

In the tube plate cleaning mode and the partition plate cleaning mode, the relay device 133 outputs the relay control signal 135.
In response, the carrier radius calculation signal 173 is sent to the microprocessor 14 via the radius calculation bus signal 137.
It is positioned to be added to 7. In these two modes of operation, position feedback signals 82 and 84 are essentially unused. Carriage command signal 125 is effective to incrementally move support carriage 26 along support arm 24 in response to carriage radius calculation signal 173.

Angular rate command signal 107 is provided as an output by divider 151. The partial pressure gauge 176 provides a tangential velocity signal 1 proportional to a predetermined tangential velocity of the nozzle device 32.
55 is generated. As previously mentioned, the predetermined tangential speed provided by the partial pressure gauge 176 is coupled to the surface to be cleaned by the nozzle device 32 at a speed fast enough to avoid damaging this surface, and yet allows the nozzle device 32 to
The tangential speed must be within a range such that the surface moves at a speed slow enough to adequately clean the surface by the water and sand mixture that exits the surface and impinges on the surface. The microprocessor 159 is a division device 151
It provides an effective radius signal 157 as an input to the . The dividing device 151 calculates a quotient (ω) having an effective radius signal 157 as the stage number and a tangential velocity signal 155 as the dividend.
It acts to create. The angular velocity command signal 107 is proportional to the quotient (ω) produced in the divider 151.

In the ball cleaning mode, microprocessor 159 accepts vertical position feedback signal 74 and carriage position feedback signal 84 as inputs. The effective radius in this mode is determined as a function of position feedback signals 74 and 84 by equation (2). In the tubesheet cleaning mode and the divider cleaning mode, the vertical position feedback signal is essentially not used and the effective radius signal 157 is essentially the same as the carriage position feedback signal 84. In the ball cleaning mode, the control arm 18
vertical angular movement is stopped and motor 91 causes control arm 18 to travel horizontally in response to horizontal position command signal 168. In the course of horizontal travel, the control arm 18 covers an angular path from 0° to 180°, measured by the angle θ in FIG. The end of the horizontal path, i.e. θ=0° or θ=
In the case of 180°, vertical movement is possible, but horizontal movement is stopped. Control arm 18 is run vertically along an incremental angular vertical path measured by angle φ in FIG. In this working mode, the angle guarantee of the vertical path is, for example, of the order of 2°. After this incremental vertical travel, the vertical movement ceases and the control arm 18 begins to travel horizontally in the opposite direction. Incremental vertical travel occurs at the end of each horizontal pass until the total angular range with many incremental verticals reaches 90°. Throughout operation of the control arm in the ball cleaning mode, the nozzle arrangement 32 of FIG.
It is designed to stop at a predetermined distance from the center 11. This is accomplished by proportional controller module 123 which is responsive to carriage command signal 125 and feedback from position feedback signal 74. The carriage radius calculation signal 174 is proportional to the predetermined distance R in FIG. 1 provided by the carriage radius calculation unit 143. Relay device 133 responsive to relay control signal 135 acts such that radius calculation bus signal 137 is the same as carrier radius calculation signal 174 . The horizontal angular velocity of the motor 91 and the control arm 18 is adjusted such that the tangential velocity of the nozzle arrangement 32 with respect to the ball-shaped surface 12 of the primary inlet chamber 10 is maintained at a predetermined tangential velocity V _T obtained from the partial pressure gauge 176. The appropriate angular velocity to achieve the predetermined tangential velocity is determined by a divider 151 responsive to the tangential velocity signal 155 and the effective radius signal 157. The angular velocity of the incremental vertical travel occurring at the end of each horizontal pass is adjusted in a similar manner to obtain the predetermined tangential velocity of the nozzle arrangement 32 relative to the ball-shaped surface.

In the tubesheet cleaning mode, the vertical position of the control arm 18 is such that the angle φ is φ=0 and the vertical movement is stopped. The control arm 18 has an angle θ from 0°.
It travels horizontally around the pivot device 20 along a path that covers an angle of 180°. Nozzle arrangement 32 is directed toward tubesheet surface 16 . The horizontal angular velocity of the control arm 19 is adjusted in the same manner as described above in which the nozzle arrangement 32 is held at a predetermined tangential velocity with respect to the tubesheet 16. At the end of each horizontal track, i.e. θ=0
At .degree. or .theta.=180.degree., the support carriage 26 undergoes incremental movement on the order of a distance of approximately 2 inches. Incremental linear movement of support carriage 26 is determined by carriage radius calculation signal 173 from carriage radius calculation signal 141.
caused by In the second working mode, relay device 133 operates in response to relay control signal 135 as well as signals 137 and 173.

In the partition plate cleaning mode, the horizontal position of the control arm 18 is fixed such that the angle θ=180° or such that the horizontal movement stops at the angle θ=0°. The control arm 18 travels through a vertical corner path such that the angle φ ranges from 0° to 90°. At the end of each vertical travel path, i.e. at angles θ of 0° and 90°, the support carriage 26 is configured such that the total amount of its incremental linear movement is as a result of the incremental movement at the end of each vertical travel path. Approximately 5 to make the movement from one end of 24 to the other end
It moves along the support arm 18 in distance increments on the order of cm (2 inches). The linear incremental movement of the support carriage 26 is
This is done in the same way as described above regarding the working mode.

Figure 6 shows the proportional controller module 103 of Figure 5.
and 113 are block diagrams of preferred embodiments. For simplicity, proportional controller module 10
Only 3 is shown in FIG. Proportional controller module 103 includes operational amplifiers 172 and 172' with feedback signals 82 and 93 connected to corresponding transcoding inputs, respectively. Amplifier 17
A programmable limit circuit 71 connected between 2 and 172' receives an angular velocity command signal 1 as an input.
Including 07. The limit circuit 174 may be, for example, an Action Instrument manufactured by Action Instrument Co.
A circuit of the type included in Action Pack 4300-112 may be used. Horizontal position command signal 105 is connected to an untranslated input of amplifier 172.

FIG. 7 shows a block diagram of a preferred embodiment of proportional controller module 123. The proportional controller module 123 is the controller module 103 shown in FIG.
It is similar in design to , but there is no speed feedback signal. The motor 40 is free to move at its natural speed, which speed may be faster or slower.
The proportional controller module 123 includes as inputs an operational amplifier 181 having the position feedback signal 74 connected to a transcoding input and the carriage command signal 125 connected to a non-transcoding input.

Computing devices 147 and 159 may be, for example, a circuit 194 including a suitably programmed microprocessor as shown in FIG. and a D/A converter, and output 125 in response to inputs 82, 84 and 137, and output 157 in response to inputs 74 and 84, respectively.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a device to be used with the control device of the present invention, FIGS. 2 to 4 are block diagrams showing the control device of the present invention from various aspects, and FIG.
8 are block diagrams showing details of selected one of the calculation blocks shown in FIGS. 2 to 4, and FIG. 9 is a block diagram showing an example of the calculation device. In the figure, 10 is a plenum (inlet chamber), 11 is the center, 12 is a ball-shaped surface, 14 is a partition plate surface, 1
6 is a tube plate surface, 18 is a control arm, 20 is a pivot device, 26 is a support carrier, 32 is a nozzle device, 35
is a manipulator, 36 is a conveyance platform feedback control device, 38 is a control arm feedback control device, 40 is a conveyance platform positioning motor, 41 is a position control device, 50 is a motor device, 52 is a position control device, and 53 is a speed control device. .

Claims (1)

Claims: 1 a pivot end connected to a pivot device inside a spherical enclosure of a steam generator having a center and fixed in position at a first predetermined distance from said center; a control arm having a nozzle arrangement for directing a mixture towards a surface of the enclosure to remove radioactive contaminants from the surface;
The nozzle device is slidably mounted on the control arm so that there is a change in linear radius from the pivot end, and the control arm is slidably mounted on the control arm so that there is a controlled change in horizontal and vertical angular position and angular velocity. It is movable around the pivot device. a tangential velocity device for generating a first set point signal proportional to a predetermined tangential velocity at which the nozzle device moves relative to the surface of the enclosure; a first feedback signal generator for generating a first feedback signal proportional to the actual linear radius of the device; and a second feedback signal generator for generating a second feedback signal proportional to the actual angular position of the control arm. and a third feedback signal generator for generating a third feedback signal proportional to the effective radius of the nozzle device in response to the first and second feedback signals; a second setpoint signal responsive to the feedback signal for generating a second setpoint signal proportional to the angular velocity required to move the nozzle arrangement at the predetermined tangential velocity;
a set point generating device; a drive device for causing angular movement of the control arm about the pivot device at the angular velocity in response to the second set point signal; and a drive device for angularly moving the control arm about the pivot device in response to the second feedback signal; and an adjustment device for adjusting the linear radius to maintain a predetermined distance between the control arm and the surface, the control arm movement control device allowing substantially uniform cleaning of the surface.