DE1095411B - Loading and unloading device for a nuclear reactor - Google Patents

Description

GERMAN

The invention relates to a loading and unloading device for a nuclear reactor with vertically extending fuel channels.

An important field of application of the invention are reactors that use a solid moderator, e.g. B. graphite and Gas cooling.

It is known to enclose a reactor core in a biological shield and the fuel elements when changing and loading, pull it out through openings in the biological shield and then again to use.

In order to ensure the necessary safety for the operating personnel, it is also necessary in the system for the Loading and changing to provide adequate shielding around the opening. Also is it is undesirable to shut down the nuclear reactor every time such operations are carried out. The fuel elements in the individual fuel channels must therefore against fresh fuel elements during operation the reactor can be replaced; the individual fuel channels are sequentially in corresponding Unloading and reloading at intervals, e.g. B. after a few days, so that a complete recharge of the reactor is carried out after a certain time.

There are known reactors with horizontal fuel channels that are loaded on one side and on the other the other side can be discharged by pushing the fuel elements through a hydraulic device will.

A loading and unloading device for a nuclear reactor, which is located on an above the reactor Unloading platform is movable and has a lifting device, with the help of which fuel elements in a magazine drum are housed, lowered into the reactor and lifted out of it can, is characterized according to the invention in that the incremental rotary movement of the magazine drum is inevitably linked to the operation of the lifting device in such a way that the lifting device is at a standstill the drum works between the movement steps.

In a facility that uses a loading chute, the chute introducing device is typically used be carried out separately from the device, which is used for inserting and replacing the fuel elements is used.

When replacing the fuel elements, the device for introducing the loading chute via the fuel channel is first used brought to introduce the gutter. The device for introducing the loading chute is then through the device for pulling out the fuel elements is replaced, which in turn is replaced by a device for inserting new fuel elements are replaced. Finally will

Loading and unloading device
for a nuclear reactor

Applicant:

AEI-John Thompson
Nuclear Energy Co. Ltd., London

Representative: Dr.-Ing. W. Reichel, patent attorney,
Frankfurt / M. I ₁ Parkstrasse 13th

Claimed priority:
Great Britain 27 February 1957

Donald Mason Sutherland, Wilmslow, Cheshire,
and Phiiip Rawson Tipper, Timperley, Cheshire

(Great Britain),
have been named as inventors

Repositioned the chute insertion device to remove the chute.

The device for introducing the fuel elements is usually identical to the unloading device and leads just another function.

As long as the fuel channel is not covered by the charger, it is by one or more closure pieces covered to prevent radiation from escaping.

In a device according to the invention, the shielding is ensured at all times. With a gas-cooled Reactor must also provide a gas-tight connection between the loading device and the loading channel to prevent radioactive or neutron-containing gases from escaping.

The chargers are preferably movable on the loading platform, e.g. B. on rails attached.

For a more detailed explanation of the subject matter of the invention, reference is now made to the drawings.

Fig. 1 is a section through the upper end of a reactor, one of which is closed by a plug Shows fuel channel;

Fig. 2 is a section through a closure piece according to Fig. 5 on an enlarged scale;

Figure 3 is a top plan view of the device of Figure 2; Fig. 4 is a section on the line IV-IV of Fig. 2;

009 679/433

3 4

5 shows a device with a loading chute, which is indicated by a flexible gas-tight connection 89 above. That

the loading opening is located; Device for removing the fuel elements is in

Fig. 6 is a corresponding view of a device carried out in the same way.

Introduction of fuel elements, which is located above the loading and unloading of the fuel elements

Fuel channel is located; 5 are the locking piece or the locking pieces

Fig. 7 shows diagrammatically a device for actuation - first from the upper part of the fuel opening -

supply of the magazine and the gripper; taken and stored in the drum. To

Fig. 8 is a side view of the fuel magazine at the completion of the loading and unloading operation

enlarged scale; they are lifted out of the drum and again

FIG. 9 is a plan view of the magazine according to FIG. 10 inserted into the fuel channel.

Fig. 8; From Figs. 2, 3 and 4 it can be seen that the closure

Fig. 10 is a side view of a fuel element; Pieces 5, 13, 14, 15 and 16 made of cement in the upper part

11 is a plan view of the fuel element of the loading chute at the top of a horizontal rail 7 of Fig. 10; have that engage the claws of a gripper

12 to 14 show the locking device can be brought to a fixed position in order to lift the locking pieces

keep the fuel elements in the magazine. and to be able to insert into the fuel channels a. the

In Fig. 1, the upper wall 1 of a pressure vessel fuel elements are housed in carriers; the

shown; on top of that are the biological exhausts have a similar horizontal rail, so that

shielding 2 and the loading platform 3. The upper part of one of the same grippers for the fuel elements and the

Fuel loading opening 4 is through a locking piece 5 20 locking pieces can be used. On both of them

sealed from cement; a cap 6 is on the upper side of the locking pieces are vertical ribs 8

End of the loading opening 4 attached. attached, which slide in grooves in the fuel channels

From the enlarged view of FIGS. 2, 3 and 4 goes and therefore keep the locking pieces aligned. the

show that the closure piece 5 made of cement on top of a fuel carrier are equipped with similar ribs,

has horizontal rail 7, which is flexible with the claws of a 25 The gripper 23 is shown in FIG. 7 on two

The gripper can be engaged to hang the cables 24 and 25 made of stainless steel

Lift the end piece out of the fuel channel or in the same direction of winding over two flat drums 26

to be able to lower it into the canal. and 27 are guided, which are fixed on a joint

Vertical shafts 28 are seated on both sides of the closure piece. This wave is made by a curling rib 8 attached, the 30 motor 52 via a gear transmission 53 and 54 in the grooves of the fuel slide and drive the locking piece aligned so that the gripper depending on the direction of rotation keep. The fuel carriers are raised or lowered with similar ribs to the winch motor, Mistake. This motor can be a controllable motor that is driven by

Fig. 5 shows in detail that a device 9 is driven by a low frequency generator, such as

for introducing a gutter 12 onto the upper end of a 35 this has already been suggested earlier.

Fuel channel has been placed, the fuel of which contains the gripper winch, which has just been described

elements are to be replaced. This device 9 also has a control device shown in FIG

two vertical channels 10 and 11. The channel 10 takes the gripper claws by various movements of the

the closure piece 5 made of cement after it has been made from both cables 24 and 25. The two cables 24 and 25,

the fuel channel has been removed, and is used for 40 the rollers lead to the gripper, run over two

temporary accommodation of the breech block. Roles 44 and 45. These roles are at the ends

A channel 12 is made from the channel 11 into the fuel by radial arms 46 and 47 attached to bevel gears 48

opening inserted, with the upper end of the channel 12 and 49 are attached, which run on the shaft 28,

by means of locking pieces 13, 14, 15 and 16 made of cement. With the two bevel gears 48, 49 there is a third

the insertion of the groove in the charger locked 45 bevel gear 50 engaged on the drive shaft of a

will. These four locking pieces lie one above the other, drive motor 51 is attached. When the engine 51

in order to shield the loading opening when the device 9 is also excited, the two bevel gears 48 and 49 run in

the channel 12 is removed and reversed by the device 19 to the opposite direction and therefore cause

lead the fuel elements is replaced. In this case that the arms 46 and 47 in opposite directions

Process, only the upper part 18 of the shield 50 will be pivoted so that they give the cable a difference

removed while the lower shield 17 imparting radial movement in place. The gripper mechanism

and place remains. therefore pivots the claws 40 below

In order to prevent the leakage of radioactive gases in the manner described. This different movement of the

Prevent being lifted by a flexible pipe or both cables is from the main movement

Hose temporarily a gas-tight seal- 55 and lowering the gripper to distinguish it,

posed. This tube has a diameter such that the differential movement of the cables 24 and 25 causes it

that the locking pieces and the channel passed through a rotary movement of the roller 31 in the gripper device

can be. tung23. This movement is transmitted to the gears 32

Fig. 6 shows the device 19 for introducing the fuel and 33, as well as transferred to a wheel 34, which with a elements. This device is coupled to the lower shield 60 type Maltese ratchet wheel 35. One twist 17 placed and contains a drum 20, which in Fig. 8 of the wheel 34 causes a pin 36 in a ge and Fig. 9 is shown in detail and the vertical slotted lever 37 engages and pivots. Here channels21 for the fuel elements. This is pivoted through the sector 38, which is the cone drum is rotated gradually when the individual wheel 39 rotates and the claws 40 of the gripper bayonet channels loaded or emptied. 65 like in and out of engagement with a fuel rod

The loading device 19 according to FIG. 6 is with the od. Like. Brings. The locking device 35 clamps the

usual shield 22 surrounded. A gripper 23 for sector 38, except when the pin 36 is in the slotted

The fuel element is firmly engaged by a device 24 lever 37.

operated, which is located above the device 19 and Figs. 10 and 11 show an embodiment

is shown separately in FIG. Also in the figure is the 70 of a fuel element used in the device 19

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5 6

can be. A rectangular frame 41 carries the certain fixed angle with respect to a zero position, perpendicular fuel element 42. The claws 40 This angle is a measure of the respective depth 7 come with the lower side of the fuel element in the fuel channel. Of the upper horizontal rail 43 (Fig. 10) in engagement. Every time it enters the channel, the gripper is

The fuel element 5 stored in the drum 20 occurs, decelerated to a progressively smaller depth, is held by the bracket 1444 of a U-shaped holder 144, as is required during loading.
(Fig. 12 to 14) added, the on both sides Depending on the rotational position in which the latch of the lower end of a fuel element container is located in the device, either the ratchet wheel 61 is hinged to the magazine, so that the bracket 1444 or 64 is driven will. When the wheel 61 extends over the lower end of the carrier. 13, the holder can be pivoted, the gear 65 and the socket 66 to the ratchet wheel 61, so that the bracket 1444 of the fuel element - in this case in the Reverse direction rotated container of the magazine is pivoted, the location of which is. The reversal means that the delay is indicated in dash-dotted lines. There is therefore a switch that moves away from the zero position and that there is enough space so that the fuel element 15 gripper is decelerated with each downward movement into the channel later and the gripper is delayed past the holder into the fuel channel 4 afterwards, as is required during unloading can be introduced below. The one is. A coil spring 67 is used to bring the ratchet leg of the holder 144 carries a pin 145, which to rotate back and therefore the delay normally in a circular groove 146 slides switch in a fixed starting position when and therefore holds the holder in the correct position. However, when a fuel container is below the gripper, ie when it is with the ratchet wheel after termination, the pin 145 of the latch 144 of the discharge or load is disengaged, through a small section of the circular groove 146 The switches operated by the cams (or

held, which is attached to a lever 147, which actuate the spring-loaded lever, the stops and can rotate about a horizontal shaft 148 and 25 allow the shaft to spin) on the shaft 54 The winch motor drives are influenced by the motor via corresponding gearwheels from a control panel will. This lever 147 moves around a circle. You control the fixed winch lift that is used for the a certain angle into the different position of the fuel elements in the core in FIG. 13 with dash-dotted lines interpreted location and takes the pin 145, which is required at. It should be noted that a number of the latch 144 is attached so that the holder opens over 30 fuel elements in each fuel channel and the fuel element and the gripper are stacked one after the other, so that the winch stroke depends on can be moved past the holder at the bottom. the amount of the brought in or taken out

When bracket 1444 sways a fuel element or fuel element.

carries a similar body, it is indicated by a See- Fig. 7 also shows the device for indexing

14 at an opening 35 of the fuel magazine 20. This device contains changes. On the holder 144 is a spring-loaded motor 69 for driving a shaft 70, the standing blocking element 149 attached. A protrusion lower end carries a ratchet wheel 71 which has a pin 72 150 on this element normally protrudes through that which is successively formed with slots 73 in the Bracket 1444 upwards. If a fuel element washer 74 at the top of the magazine drum 20 comes into engagement 40 lowered into the fuel container by the gripper.

has been, presses the underside of the fuel element The movements follow one another so that

the protrusion 150 down and therefore normally rotates the one fuel carrier in a channel 21 Locking element 149 held against the action of a spring 152 by a holder of the type described A hook 153 of the locking element now comes with it. He will first engage with the griffin he is stealing a fixed tooth 151 in engagement and preventing each 45 from being brought and moved past the locking element 149, Movement of the holder 144. When the fuel element being released the lock and the fuel carrier is lifted by the gripper, the lock is lowered. The gripper is then released after loosening element 149 raised by the spring 152, so that that of the fuel element is raised again; he will then Hook 153 can pass the fixed tooth 151. then raised another bit, The holder 144 can then be opened. 50 so that he can get off the drum. The drum

An electromechanical brake can then be switched one step further until the The engine's drive shaft is attached to the winch and the next fuel duct is in position can inevitably be repeated at the end of the controlled stroke or during the process. The additional emergency to slow down. The shaft 54 is lifted by the gripper when indexing the magazine Winch gear driven so that its rotation at 55 is carried out in the following way: The differential der The rotation of the winch and therefore also with the height of the drive motor 51 is on a support frame 29 gripper is synchronized. The shaft 54 carries cam bearings which rotate around a shaft 28 as an axis. One washers 55 and 56, which actuate switches 57, 58, movement of the support frame 29 is therefore via the to control the specific gripper stroke. The shaft 54 transmits bevel gears 48 and 49 to the arms 46 and 47 also the switch assembly that the progressive 60 carry so that the arms are common and not decreasing height controls at which the grippers move against each other. The gripper is therefore around Channel while loading or unloading braked a small amount raised or lowered, namely will. For this control, a lever 59 on the shaft 54 is independent of the main drive that attaches the winding, when rotating a pawl 60 at the end drum 26 and 27 drives. The movement of the yard Gripper stroke is actuated and a controlling switch 65 29 is controlled by a crank 75, which on wheel 61 is moved further by one tooth. At the top a shaft 76 is attached. The opposite end The area of this ratchet wheel is a shaft that controls the deceleration and is controlled by a guide lever 77, which is connected to it of the switch piece 62 attached, which is connected to contacts 63 of a guide groove 78 of a rotating drum 79 comes into contact. The switch piece 62 moves in engagement, controlled so that it moves in a front each time, when the pawl is operated it is pivoted in a 70 written manner. The drum 79

is mounted on the shaft 70 which is driven by the indexing motor of the magazine. When the magazine is driven, the drum rotates one revolution when the magazine is moved further and lifts the gripper from one container of the magazine and lowers it back to its original height in the next container. With this arrangement, the gripper becomes automatic together with its claws raised so that it does not interfere with the fuel element in the magazine when the magazine is in the prescribed position Way is rotated in a discharge cycle. The grab is lowered onto a fuel element, after the magazine has been rotated during a loading process.

In the device described, the bearings that are exposed to radiation are not with a Lubricant lubricated, which is affected by the radiation.

Claims (7)

Patent claims: 1. Loading and unloading device for a nuclear reactor, which is movable on an unloading platform located above the reactor and has a lifting device with the help of which fuel elements, which are housed in a magazine drum, can be lowered into the reactor and lifted out of it, characterized in that that the stepwise rotary motion of the magazine drum is associated with the operation of the lifting device positively in such a way that the lifting device works at a standstill of the drum between the movement steps. 2. Apparatus according to claim 1, characterized in that the magazine drum for shielding serving closure pieces can accommodate and contains facilities that the fuel elements and allow the breeches to move back and forth between the magazine drum and the loading opening. 3. Apparatus according to claim 1 or 2, characterized in that a loading device for a Loading chute, which can be inserted into the loading opening, provided and provided with devices is, which receive the closure pieces while the loading chute is inserted, and which these or insert other stoppers into the loading opening after inserting the loading chute into the loading opening or has been taken out. 4. Apparatus according to claim 1 or one of the following, characterized in that it is on the Loading platform can be moved on rails. 5. Apparatus according to claim 2 or one of the following, characterized in that the magazine drum is rotatable about a vertical axis and a number of holders at the lower end of the Contains containers or carriers on which the fuel elements rest and means for retraction the holder, so that one fuel element at a time can be lowered from the holder. 6. Apparatus according to claim 1 or one of the following, characterized in that the device for lifting and lowering the locking pieces or fuel elements from a gripper consists, which is lowered into the loading opening and engages a fuel element or plug can be brought, which is also carried by cables that are operated in the same sense, to raise or lower the grapple, and to operate in different ways to move it with to disengage or engage a fuel element or plug. 7. Apparatus according to claim 3 or one of the following, characterized in that the charger for the fuel elements and the device for introducing the loading chute a common one Have base so that the device for introducing the loading chute is set over a loading opening and that after the insertion of the loading chute is completed, only the upper part of the device is removed and the base remains in place with the top of the charger for the fuel elements can be placed on the base, and vice versa. Considered publications:
French Patent No. 1 108 407;
U.S. Patent Nos. 2,725,993, 2,782,158. For this purpose 2 sheets of drawings © 009 679/433 12.60