An apparatus and method for fuel assembly main component chrome scale removal cleaning

Abstract

The present application relates to the field of fuel assembly, especially to a device and method for removing chromium chips from the main component of fuel assembly, which comprises cleaning tanks, spraying tanks and drying tanks arranged in parallel and equidistantly, the cleaning tanks, the spraying tanks and the drying tanks are all vertical structures, and each of them is provided with at least two processing positions inside; an up-and-down feeding turnover mechanism is arranged on the left side of the cleaning tank; the frame is the skeleton of the whole device and is divided into three layers; the control cabinet is located on the leftmost side of the frame and integrates the control system of the whole device; the travelling crane system is located on the top layer of the frame and can move between different tank positions and the up-and-down feeding turnover mechanism, and is used for transferring the main component between different tank bodies. The vertical cleaning method is adopted to improve the cleaning effect.

Description

Technical Field

[0001] This invention relates to the field of fuel assemblies, and more particularly to an apparatus and method for cleaning chromium-depleted main components of fuel assemblies. Background Technology

[0002] The main component of the fuel assembly is a square prism no longer than 1.5m, containing numerous cavities extending along its length. During the manufacturing process, a large amount of chromium coating debris accumulates in these cavities. Removing chromium debris and other residues from the main component is a crucial step in the entire assembly manufacturing cleaning process, and strict requirements are placed on the cleanliness of the main component.

[0003] Currently, horizontal square tanks are used to clean the main components. The main components are placed horizontally inside different tanks and cleaned by ultrasonication, bubbling, spraying, and drying. After multiple tests, it was found that the existing equipment could not completely remove the chromium residue inside the cavities of the main components, and the cleanliness of the product could not meet the standards, often requiring rewashing. The main reasons for the failure to meet the cleanliness standards are: (1) In the entire cleaning process, the main components are placed horizontally in the working tank. Bubbling and ultrasonic cleaning can only treat the surface of the main components, and the ability to treat chromium residue in the cavities of the main components is limited; (2) Due to the static electricity and the surface tension of water, the residual chromium residue in the compressed air drying method will be adsorbed on the flow channel wall. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide an apparatus for cleaning chromium shavings from the main components of a fuel assembly, which adopts a vertical cleaning method and improves the cleaning effect.

[0005] This invention provides an apparatus for cleaning chromium deposits from the main components of a fuel assembly, comprising:

[0006] The cleaning tank, blowing tank and drying tank are arranged side by side at equal intervals. All three tanks are vertical structures and each has at least two processing positions inside.

[0007] The upper part of the cleaning tank is connected to the heating water tank via a spray water supply pipe. The top of the heating water tank is connected to the upper limit of the water level in the cleaning tank via a return water pipe. A first water pipe and a second water pipe are installed on the side wall of the heating water tank.

[0008] The drain pipe at the bottom of the cleaning tank is connected to the spray water supply pipe of the cleaning tank through a circulation pipeline. A circulation pump, a primary filter, and a secondary filter are connected in sequence on the circulation pipeline. The first water pipe is connected to the inlet side of the primary filter in the circulation pipeline. The second water pipe is connected to the outlet side of the secondary filter in the circulation pipeline.

[0009] A spray pipe is installed at the upper end of the interior of the cleaning tank; symmetrical side ultrasonic transducers are installed below the spray pipe, and a bottom ultrasonic transducer is installed at the bottom of the tank; a cleaning tank guide frame is also installed inside the tank to guide the material basket to move vertically up and down inside the tank; a bubble tube is installed below the cleaning tank guide frame.

[0010] The drying tank is connected to an air collection box, which is connected to an air outlet pipe, a hot air filter box, a hot air circulation pump, and a heating pack. The other end of the heating pack is connected to the tank body of the drying tank.

[0011] The left side of the cleaning tank is equipped with a loading and unloading tilting mechanism, which switches the main component between vertical and horizontal positions to serve as the loading and unloading position for the device; the frame is the skeleton of the entire device and is divided into three layers; the control cabinet is located on the far left of the frame and integrates the control system of the entire device; the traveling system is located on the top layer of the frame and can move between different tank positions and the loading and unloading tilting mechanism to transfer the main component between different tanks.

[0012] In one specific embodiment of the present invention, two rows of ultrasonic transducers are arranged at equal intervals inside the side ultrasonic transducer plate, with 18 to 25 ultrasonic transducers in each row and an interval of 4 to 6 cm; the interval between the two rows of ultrasonic transducers is 10 to 16 cm, so that they are exactly aligned with the two main components inside the material basket.

[0013] Five to ten ultrasonic transducers are arranged at equal intervals inside the bottom ultrasonic transducer plate, directly facing the bottom of the main component inside the basket.

[0014] In one specific embodiment of the present invention, a pair of limiting plates are provided at the top of the blowing trough; two sets of blowing pipes are provided on the upper part of the side wall of the blowing trough, and the blowing pipes are located above the material basket when the material basket is placed in the trough.

[0015] The spray nozzles of the spray pipe are arranged in three layers at equal intervals, with 8 to 16 nozzles in each layer; a spray pipe guide frame is installed in the spray trough to guide the material basket to move vertically up and down in the trough.

[0016] A ring of dispersed jet outlets is set at the bottom of the tank, and the gas in the tank is collected and discharged along a fixed pipeline.

[0017] In one specific embodiment of the present invention, a pair of drying tank limiting plates are provided on the top of the drying tank, and a heat insulation layer is wrapped around the outside of the tank body;

[0018] The tank is equipped with an air collection layer, and multiple air collection ports are set at the top and bottom of the air collection layer to collect the hot air in the tank into the air collection layer, and then the gas in the tank is discharged through the air collection box.

[0019] A drying trough guide frame is installed inside the trough to guide the material basket to move vertically up and down.

[0020] In one specific embodiment of the present invention, a set of hot air plates is provided below the air collecting box. When the material basket is placed in the trough, the hot air plates can wrap around the main component. The set of hot air plates consists of two side hot air plates and one bottom hot air plate. Each hot air plate has evenly distributed air outlet holes on its inner side. The hot air plates are connected by connecting pipes. After the hot air enters from the air inlet of the hot air plate, it is guided by the hot air plate and blown from the air outlet to various parts of the main component to achieve a uniform drying effect.

[0021] In one specific embodiment of the present invention, the loading and unloading tilting mechanism and the transfer trolley cooperate to realize the transfer of the main component;

[0022] The main body of the loading and unloading tilting mechanism is the tilting mechanism frame. When the tilting mechanism frame is placed horizontally, a pair of material basket guide rollers are set at its bottom. The tilting mechanism frame is driven by the tilting mechanism drive motor, and the tilting is achieved through the tilting mechanism transmission gear.

[0023] The top of the transfer trolley is equipped with a row of rollers, and a stop bar is installed above the end rollers. One end of the stop bar is connected to the frame of the transfer trolley, and the other end can be flipped freely. When the material basket is loaded, it closes to prevent the material basket from slipping.

[0024] In one specific embodiment of the present invention, a pair of guide rails are horizontally mounted on the upper layer of the frame, and the trolley moves on the guide rails.

[0025] The trolley is equipped with a main support; the hoist motor is installed on the main support; the hook is connected to the bottom of the hoist motor, and the hoist motor drives the hook to rise or fall in the middle space of the frame; the mobile motor is installed on the trolley to drive the trolley to move laterally on the guide rail, and the trolley can be controlled by the trolley controller.

[0026] The bottom layer of the frame is equipped with a control cabinet, a loading and unloading tilting mechanism, a cleaning tank, a blowing tank, and a drying tank;

[0027] The middle layer of the rack is the personnel operation area.

[0028] In one specific embodiment of the present invention, a basket lifting device is suspended on the hook. The top of the basket lifting device is a lifting plate, and below the lifting plate is a lifting beam, which can be placed on the limiting plates of the three troughs to suspend the basket in the trough. The lifting beam is connected to the lifting rod below, and its bottom is fork-shaped with two holes. After the lifting plate of the basket is inserted into the fork, a buckle is inserted, and the buckle cover is placed on the buckle to complete the connection between the basket lifting device and the basket. Conversely, the lifting device can be removed from the basket.

[0029] In one specific embodiment of the present invention, the material basket includes:

[0030] Material basket tooling rack

[0031] The basket tooling frame has three pairs of clamping plates arranged equidistantly along its length. Each pair of clamping plates consists of an upper clamping plate, a lower clamping plate, and a pair of knurled handle screws.

[0032] The lower clamping plate is fixed to the material basket fixture frame, and the upper clamping plate is fixed to the lower clamping plate by knurled handle screws. The tightness of the knurled handle screws can be adjusted manually to fix the position of the main component. A bottom clamping plate is fixed to the bottom of the material basket. The bottom clamping plate has a square hole with half depth to lock the bottom of the main component. A top baffle is installed on the top of the material basket fixture frame. It has evenly distributed round holes to block some foreign objects while keeping the water and air flow unobstructed. A hanging plate is set at the center of the top of the material basket and connected to the material basket lifting device.

[0033] This invention provides a method for cleaning chromium deposits from the main components of a fuel assembly, comprising the following steps:

[0034] Step 1: Place the workpiece to be cleaned in the material basket, push it into the loading and unloading tilting mechanism using a transfer trolley, tilt the material basket to a vertical position, install the lifting device, and use an overhead crane to lift it.

[0035] Step 2: Hoist the main component from the loading and unloading station to the cleaning station in the cleaning tank; the hot water in the cleaning tank is filtered in two stages and sprayed onto the main component for 5-10 minutes, ultrasonic cleaning for 30-40 minutes, and bubble cleaning for 5-10 minutes. The ultrasonic and bubble cleaning cycles are repeated at least twice; the cleaning water must be Grade A water with a temperature between 70-90℃.

[0036] The cleaning water generated during cleaning is discharged from the cleaning tank and then filtered twice before being returned to the cleaning tank for reuse.

[0037] Step 3: Hoist the main component from the cleaning station to the blowing station; raise and lower the material basket so that the blowing pipe can fully blow the main component to all parts. After raising and lowering several times, observe the residual moisture inside the main component and select to use an air gun for fixed-point blowing.

[0038] Step 4: Hoist the main component from the blowing station to the drying station; dry with hot air for 30-40 minutes at a temperature of 70-90℃;

[0039] Step 5: The main component is hoisted from the drying station to the loading and unloading station; the material basket lifting device is disassembled, the loading and unloading tilting mechanism is operated to a horizontal position, the material basket is pulled out to the transfer trolley, and the material basket is disassembled to take out the main component.

[0040] Compared with the prior art, the apparatus for cleaning chromium deposits from the main components of fuel assemblies of the present invention has the following advantages:

[0041] (1) The chromium removal cleaning process on the inner and outer surfaces of the main components is completed in one go in the workpiece chromium removal cleaning device. This device adopts a vertical cleaning method, which ensures that the direction of water flow and airflow is consistent with the extension direction of the workpiece cavity during the cleaning process. This facilitates the fluid to pass through all cavities in the component, enhances the flushing effect of water flow and airflow, and improves its cleaning ability. The original function that required multiple slots is integrated into 3 slots, reducing the workpiece hoisting and transfer process and reducing the risk of dropping and bumping during transfer.

[0042] (2) The cleaning process combines spraying, ultrasonic cleaning, and bubbling cleaning methods. Spraying cleaning removes easily detachable residues from the workpiece's outer surface using sprayed water; ultrasonic cleaning uses high-frequency ultrasonic waves to break up residues, allowing them to detach effectively; bubbling cleaning uses compressed air injected from the bottom of the tank to enhance the agitation of the water within the tank, thereby optimizing the scouring effect of the water flow on the component cavities. Circulating hot air is used to blow on the workpiece, accelerating component drying and removing residual moisture and a small amount of chromium shavings after cleaning.

[0043] (3) The entire device is located above ground, with the space divided into three layers by constructing a frame in the tank area. The top layer is a crane system used for hoisting workpieces; the middle layer is the operator's work area, where operators can operate on different tanks and workpieces to be cleaned; the bottom layer houses most of the equipment and piping that constitute the device. During operation, workpieces are loaded using baskets, each capable of holding multiple components, allowing the device to clean multiple components simultaneously in different processes. A tilting mechanism is used to switch the workpieces between vertical and horizontal positions during loading and unloading.

[0044] (4) Set up a circulation pipeline to reduce wastewater discharge and save costs. Attached Figure Description

[0045] Figure 1 A schematic diagram of the device used for cleaning chromium deposits from the main components of the fuel assembly;

[0046] Figure 2 A schematic diagram showing the main structure and connection relationships of the device;

[0047] Figure 3 A schematic diagram showing the cleaning tank and its related structural connections;

[0048] Figure 4 This diagram shows the internal structure of the cleaning tank.

[0049] Figure 5 This diagram shows the structure of the spray pipe in the cleaning tank.

[0050] Figure 6 A schematic diagram of a lateral ultrasonic transducer structure;

[0051] Figure 7 A schematic diagram of the bottom ultrasonic transducer structure;

[0052] Figure 8 A schematic diagram of the bubbling tube structure;

[0053] Figure 9 This diagram shows the internal structure of the jet vent.

[0054] Figure 10 This diagram shows the nozzle structure.

[0055] Figure 11 A schematic diagram of the drying tank and its related structures;

[0056] Figure 12 This diagram shows the internal structure of the drying tank.

[0057] Figure 13 This diagram shows the structure of the hot air plate.

[0058] Figure 14 A schematic diagram showing the structure of the loading / unloading tilting mechanism and the transfer trolley;

[0059] Figure 15 This diagram shows the overall structure of the driving system.

[0060] Figure 16 This diagram shows the structure of the material basket lifting device.

[0061] Figure 17 A schematic diagram showing the material basket and workpiece structure;

[0062] In the diagram, 1-washing tank, 2-spraying tank, 3-drying tank, 4-main component, 5-spray pipe nozzle, 6-side ultrasonic transducer plate, 7-washing tank guide frame, 8-bubbling pipe, 9-bottom ultrasonic transducer plate, 10-spray pump, 11-secondary filter, 12-primary filter, 13-circulation pump, 14-heating water tank, 15-spraying pipe, 16-spraying tank guide frame, 17-drying tank guide frame, 18-heating pack, 19-hot air circulation pump, 20-washing tank drain valve, 21-circulation water outlet valve, 22-heating water tank outlet valve, 23-inlet valve, 24-washing tank inlet valve, 25-heating water tank inlet valve, 26-spray pump outlet valve, 27-heating water tank drain valve, 28-addressing pump outlet valve. 29-Water filling valve for hot water storage tank; 30-Drain valve for spray trough; 31-Drain valve for drying trough; 32-Drain valve for heating pack; 33-Return water pipe; 34-Traffic system; 35-Frame; 36-Moving door; 37-Frame enclosure; 38-Step ladder; 39-Control cabinet; 40-Loading and unloading tilting mechanism; 41-Transfer trolley; 42-Material basket; 43-Ultrasonic generator; 44-Material basket fixture frame; 45-Knurled handle screw; 46-Upper clamping plate; 47-Lower clamping plate; 48-Bottom clamping plate; 49-Top baffle; 50-Hanging plate; 51-Hanging beam; 52-Hanging rod; 53-Snap ring cover; 54-Pull buckle; 55-Tilting mechanism frame; 56-Basket guide rail roller; 57-Tilting mechanism 58-Drive motor, 59-Tilting mechanism transmission gear, 60-Transfer trolley frame, 61-Roller, 62-Spray water supply pipe, 63-Circulation pipeline, 64-Second drain pipe, 65-Second water pipe, 66-First drain pipe, 67-First water pipe, 68-Heating water tank drain pipe, 69-Heating rod, 70-Deionized water pipe, 71-Heating water tank manual cover, 72-Spray pipe, 73-Manual cover, 74-Limiting plate, 75-Bottom sealing plate of cleaning tank, 76-Cleaning tank support leg, 77-Side lead pipe, 78-Side vibrating plate, 79-Side ultrasonic transducer, 80-Bottom lead pipe, 81-Bottom vibrating plate, 82-Bottom ultrasonic transducer, 83-Bubble tube support, 84-Bubble tube 85-Limiting plate, 86-Puffing air inlet pipe, 87-Puffing trough air outlet, 88-Puffing trough exhaust pipe, 89-Puffing trough sealing plate, 90-Puffing trough drain pipe, 91-Puffing trough support leg, 92-Air collection box, 93-Air outlet pipe, 94-Hot air filter box, 95-Drying trough limiting plate, 96-Air collection partition, 97-Hot air plate, 98-Drying trough guide frame, 99-Hot air plate connecting pipe, 100-Hot air plate air inlet, 101-Drying trough sealing plate, 102-Drying trough support leg, 103-Drying trough drain outlet, 104-Cycle motor, 105-Main support, 106-Moving motor, 107-Tractor, 108-Tractor guide rail, 109-Tractor controller, 110-Tractor hook. Detailed Implementation

[0063] To further understand the present invention, embodiments of the present invention are described below in conjunction with examples. However, it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, and not for limiting the present invention.

[0064] Embodiments of the present invention disclose an apparatus for cleaning chromium deposits from the main components of a fuel assembly, such as... Figure 1 As shown, it includes:

[0065] The cleaning tank 1, the blowing tank 2, and the drying tank 3 are arranged side by side at equal intervals, forming the main body of the entire device, such as... Figure 2 As shown;

[0066] like Figure 3 As shown, the upper part of the cleaning tank 1 is connected to the heating water storage tank 14 through the spray water supply pipe 62. The spray water supply pipe 62 is equipped with a spray pump 10 for pressurizing deionized water. The spray water supply pipe 62 is also equipped with a spray pump outlet valve 26.

[0067] The heating water storage tank 14 is set independently. The water storage tank can store more water than the volume of the cleaning tank. Four sets of heating rods 69 are arranged at the bottom and a manual cover 71 is set at the top.

[0068] The top of the heated water storage tank 14 is connected to a deionized water pipe 70 for adding water. A water inlet valve 28 for the heated water storage tank is installed on the deionized water pipe 70.

[0069] A return water pipe 32 is connected to the top of the heating water storage tank 14 and the upper limit of the water level in the cleaning tank 1. When the water level in the cleaning tank 1 exceeds the limit, the water inside will flow into the heating water storage tank 14 through the return water pipe 32.

[0070] A drain pipe 68 is provided on the bottom or side wall of the heating water tank 14, and a drain valve 27 is provided on the drain pipe 68 to directly discharge waste liquid for treatment.

[0071] A first water pipe and a second water pipe are installed on the side wall of the heating water storage tank 14. The first water pipe is equipped with a heating water storage tank outlet valve 22, and the second water pipe is equipped with a heating water storage tank inlet valve 25.

[0072] The first drain pipe 66 at the bottom of the cleaning tank 1 is connected to the cleaning tank 1 through the circulation pipe 63;

[0073] A circulation pump 13, a primary filter 12, and a secondary filter 11 are connected sequentially to the circulation pipeline 63.

[0074] The first water pipe is connected to the inlet side of the primary filter 12 in the circulation pipeline;

[0075] The second water pipe is connected to the outlet side of the secondary filter 11 in the circulation pipeline;

[0076] An inlet valve 23 is provided on the inlet side of the primary filter 12;

[0077] A cleaning tank inlet valve 24 is installed on the outlet side of the secondary filter 11;

[0078] A circulating water valve 21 is installed on the first drain pipe 66 of the cleaning tank 1;

[0079] A cleaning tank drain valve 20 is installed on the second drain pipe 64 of the cleaning tank 1, and the second drain pipe 64 is connected to the first drain pipe 66.

[0080] The present invention sets up two water circulation loops. The first water circulation loop returns the cleaning water in the cleaning tank 1 to the cleaning tank 1 after two-stage filtration treatment. Specifically, the cleaning water in the cleaning tank 1 is drawn by the circulation pump 13 through the circulation outlet valve 21, flows through the inlet valve 23, the first-stage filter 12, the second-stage filter 11, and the cleaning tank inlet valve 24 before returning to the cleaning tank 1.

[0081] The second water circulation loop returns the water in the heating water storage tank 14 to the heating water storage tank 14 after two-stage filtration. Specifically, the water in the heating water storage tank 14 is drawn by the circulation pump 13 through the heating water storage tank outlet valve 22, flows through the inlet valve 23, the first-stage filter 12, the second-stage filter 11, and the heating water storage tank inlet valve 25 before returning to the heating water storage tank 14.

[0082] The internal structure of cleaning tank 1 is as follows Figure 4 As shown, a pair of limiting plates 74 are installed at the top of the tank for suspending the material basket 41. A pair of manual covers 73 can be placed at the tank opening to close the tank during operation. Two sets of spray pipes 72 are installed at the upper part of the tank interior; when the material basket 41 is placed inside the tank, the spray pipes 72 are positioned above the material basket 41. The detailed structure of the spray pipes is shown below. Figure 5 As shown, the spray nozzles are arranged symmetrically in two layers, with a total of 8 nozzles in each layer. During operation, the nozzles can spray water diagonally downwards from above the main component 4.

[0083] The tank is also equipped with two symmetrical side ultrasonic transducers 6, which are located below the spray pipe 72.

[0084] A bottom ultrasonic transducer 8 is installed at the bottom of the tank. After the material basket 41 is placed in the tank, the ultrasonic transducer can wrap the main component 4 inside the entire material basket 41, so as to send ultrasonic waves from the two sides and the bottom, penetrating the entire main component 4.

[0085] Lateral ultrasonic transducer plate 6 structure as follows Figure 6As shown, two rows of lateral ultrasonic transducers 79 are arranged at equal intervals inside, with 18 transducers 79 in each row and a spacing of 6 cm. The two rows of lateral ultrasonic transducers are spaced 16 cm apart, so that they are directly aligned with the two main components 4 inside the material basket 41. The lateral ultrasonic transducers 79 are encapsulated by lateral transducer plates 78, which can conduct the sound waves generated by the ultrasonic transducers. The lateral ultrasonic transducer plate 6 extends out of the cleaning tank through a lateral lead tube 77, and is electrically connected to the ultrasonic generator 42. The bottom ultrasonic transducer plate 8 has the following structure. Figure 7 As shown, five bottom ultrasonic transducers 82 are arranged at equal intervals inside the device, facing the bottom of the main component 4 inside the basket 41. The bottom ultrasonic transducers are encapsulated by a transducer plate 81, which can also transmit the ultrasonic waves generated by the transducers. The bottom ultrasonic transducer plate 9 extends out of the cleaning tank through a bottom lead tube 80, and is electrically connected to the ultrasonic generator 42.

[0086] A stainless steel guide frame 7 is installed inside the tank to guide the material basket 41 vertically up and down within the tank. A bubble tube 8 is installed below the guide frame 7; its detailed structure is as follows... Figure 8 As shown. Compressed air enters from the inlet of the bubbling tube, branches out, and overflows from the eight bubbling tube outlets 84, disturbing the water in the cleaning tank 1.

[0087] A square bottom sealing plate 75 is installed on the side bottom of the cleaning tank 1. It is normally sealed with bolts, but can be opened for maintenance to facilitate work inside the tank. Three cleaning tank support legs 76 are arranged at equal angles around the bottom of the cleaning tank 1 to support the entire tank.

[0088] The internal structure of the jet trough 2 is as follows: Figure 9 As shown. A pair of limiting plates 85 are installed at the top to hold a manual cover to block the slot opening. Two sets of blowpipes 15 are installed on the upper side wall of the blowpipe 2; when the material basket 41 is placed inside the trough, the blowpipes 15 are positioned above the material basket 41. The detailed structure of the blowpipe 15 is shown below. Figure 10 As shown. The nozzles of the spray pipe 15 are arranged in three layers at equal intervals, with a total of 8 nozzles in each layer. During operation, the nozzles can spray diagonally downwards from above the main component 4. A spray pipe guide frame 16, made of stainless steel, is installed inside the spray tank 2 to guide the material basket 41 to move vertically up and down within the tank. A ring of dispersed spray tank outlets 87 is provided at the bottom of the tank to collect the gas inside the tank and discharge it along fixed pipelines.

[0089] A square spray trough sealing plate 89 is provided on the bottom side of the spray trough 2, and three spray trough support legs 91 are arranged at equal angles around the bottom.

[0090] The bottom of the jet trough 2 is provided with a jet trough drain pipe 90, and a jet trough drain valve 29 is provided on the jet trough drain pipe 90.

[0091] like Figure 11As shown, an air collecting box 92 is connected above the drying tank 3. The air collecting box 92 is connected to an air outlet pipe 93, a hot air filter box 94, a hot air circulation pump 19, and a heating pack 18. The other end of the heating pack 18 is connected to the tank body of the drying tank 3. The gas in the tank passes through the air outlet pipe 93 and the hot air filter box 94, is drawn by the hot air circulation pump 19, injected into the heating pack 18, and then re-enters the drying tank, forming a hot air circulation heating and filtration system. The filter box 94 mainly filters excess moisture and particles in the gas; the heating pack 18 has multiple bending heating rods arranged inside to increase the heating area and improve the heating rate.

[0092] The bottom of the heating pack 18 is provided with a heating pack drain pipe, and a heating pack drain valve 31 is provided on the heating pack drain pipe.

[0093] The internal structure of drying tank 3 is as follows Figure 12 As shown. Similar to the cleaning tank 1 and the blowing tank 2, a pair of drying tank limiting plates 95 are provided on the top, which can be used to place a manual cover plate to block the tank opening. A heat insulation layer is wrapped around the outside of the tank to reduce heat dissipation during the hot air circulation process. The air collecting box 92 is located at the top of the tank, and an air collecting partition 96 is provided inside the tank. Multiple air collecting ports are provided at the top and bottom of the air collecting partition 96 to collect the hot air in the tank into the air collecting partition 96, and then the gas in the tank is discharged through the air collecting box 92. The same drying tank guide frame 98 is provided inside the tank to guide the material basket 41 to move vertically. A set of hot air plates 97 is provided below the air collecting box 92. When the material basket 41 is placed in the tank, the hot air plates 97 can cover the main component 4. Its detailed structure is shown in the figure. Figure 13 As shown. This set of hot air plates 97 consists of two side hot air plates and one bottom hot air plate. Each hot air plate 97 has evenly distributed air outlet holes on its inner side. The hot air plates are connected by connecting pipes. Hot air enters from the air inlet 100 of the hot air plate and is guided by the hot air plate 97, and blown from the air outlet holes to various parts of the main component 4 to achieve a uniform drying effect.

[0094] A square drying tank cover plate 101 is provided on the bottom side of the drying tank 3, and three drying tank support legs 102 are arranged at equal angles around the bottom.

[0095] A drying tank drain outlet 103 is provided at the bottom of the drying tank 3, and a drying tank drain valve 30 is provided on the drying tank drain outlet 103.

[0096] The drain pipes of cleaning tank 1, blowing tank 2, drying tank 3, and heating pack 18 are all connected to the wastewater discharge pool.

[0097] A loading / unloading tilting mechanism 39 is installed on the left side of the cleaning tank 1, which switches the main component 4 between vertical and horizontal positions, serving as the loading / unloading position for the device; the frame 34 is the skeleton of the entire device, enclosing the entire device and dividing it into three layers; the control cabinet 38 is located on the far left of the frame, integrating the control system of the entire device; the traveling system 33 is located on the top layer of the frame 34, integrating the trolley body and a pair of guide rails, enabling it to move between different tank positions and the loading / unloading tilting mechanism 39; the transfer trolley 40 and the material basket 41 are auxiliary components used for loading and transferring the main component 4.

[0098] The entire device is located above ground, with the three slots approximately 2.7m high. To facilitate operator access at the slot openings, the device is divided into three levels. The top level, approximately 0.9m high, houses the overhead crane system for hoisting the main component 4. The middle level, approximately 3.1m high, is the operator's activity area. Operators access the middle level via ladder 37. This area is protected by a sliding door 35 and a frame railing 36, with baffles connecting the slot openings. In this area, operators can directly touch the slot openings, operate the overhead crane to hoist the main component 4, and manage different slots. The bottom level, approximately 1.9m high, houses most of the equipment and piping that constitute the device.

[0099] The loading / unloading tilting mechanism and the transfer trolley are used for tilting and transferring the main component 4, and their structure is as follows: Figure 14 As shown. The loading and unloading tilting mechanism 39 is located on the left side of the cleaning tank 1 and is connected to the frame. The tilting mechanism frame 55 is the main body of the mechanism. When the mechanism is placed horizontally, there is a pair of material basket guide rollers 56 at its bottom, which are used to push and pull the material basket in and out of the loading and unloading tilting mechanism. The mechanism can tilt between horizontal and vertical positions. It is driven by the tilting mechanism drive motor 57 and the tilting mechanism transmission gear 58 realizes the transmission tilting.

[0100] The transfer trolley 40 mainly works in conjunction with the loading and unloading tilting mechanism 39 to realize the transfer of the main component 4. Its main body is the transfer trolley frame 59, with four universal wheels at the bottom; a row of rollers 60 is installed on the top of the transfer trolley frame, and the space above the rollers 60 is just enough to place the material basket 41 horizontally, which facilitates the pushing of the material basket 41; a stop bar 61 is set above the end rollers, one end of the stop bar 61 is connected to the transfer trolley frame 59, and the other end can be flipped freely, which can close up when the material basket 41 is loaded to prevent the material basket 41 from slipping.

[0101] The hoisting process of main component 4 is completed by the crane system, and its overall structure is as follows: Figure 15As shown. The overhead crane system includes a pair of guide rails 108, which are horizontally mounted on the upper layer of the frame, allowing the overhead crane 107 to move laterally above the frame and transfer the main component 4 between different troughs and loading / unloading tilting mechanisms. A main support 105 is mounted on the overhead crane 107. A hoist motor 104 is a lifting drive motor, mounted on the main support 105; a hook 110 is connected to the bottom of the hoist motor 104, and the hoist motor drives the hook 110 to rise or fall within the middle layer of the frame. A moving motor 106 is mounted on the overhead crane 107 to drive the overhead crane 107 to move laterally on the guide rails, and a motor cover is provided to protect the internal transmission mechanism. The entire overhead crane can be controlled by the overhead crane controller 109 or operated on the control panel of the control cabinet.

[0102] During the use of this device, the main component 4 is always placed inside the basket 41 for hoisting, loading, and protection. Its main structure is as follows: Figure 17 As shown. The basket fixture 43 forms the main support of the basket 41 and is made of stainless steel. Three pairs of clamping plates are arranged equidistantly along the length of the basket fixture 43. Each pair of clamping plates consists of an upper clamping plate 45, a lower clamping plate 46, and a pair of knurled handle screws 44. All of them are made of PEEK. The lower clamping plate 46 is fixed to the basket fixture 43, and the upper clamping plate 45 is fixed to the lower clamping plate 46 by the knurled handle screws 44. The knurled handle screws 44 can be manually adjusted to fix the position of the main component 4. A bottom clamping plate 47 made of PEEK is fixed to the bottom of the basket 41. The clamping plate has a square hole with half the depth to lock the bottom of the main component 4. A top baffle 48 made of stainless steel is installed on the top of the fixture and has evenly distributed round holes to block some foreign objects while keeping the water and air flow unobstructed. A hanging plate 49 is set at the center of the top of the basket 41 and connected to the basket lifting device.

[0103] The material basket 41 is suspended within the trough and used for hoisting between different workstations using a material basket lifting device. The material basket lifting device is as follows: Figure 16 As shown. The top of the lifting device is a lifting plate 50, which can be connected to the crane hook; below the lifting plate 50 is a lifting beam 51, which can be placed on the limiting plates of the three troughs to suspend the material basket 41 in the trough; below the lifting beam is a lifting rod 52, which is forked at the bottom with two holes. After the lifting plate 49 of the material basket is inserted into the fork, the buckle 54 is inserted and the retaining ring cover 53 is placed on the buckle 54 to complete the connection between the material basket lifting device and the material basket 41. Conversely, the lifting device can be removed from the material basket 41.

[0104] The device is equipped with four functional operation stations: loading and unloading tilting, cleaning, blowing, and drying. These correspond to the loading and unloading tilting mechanism 39, the cleaning tank 1, the blowing tank 2, and the drying tank 3, respectively.

[0105] During operation, the main component 4 is loaded into the material basket 41 and pushed into the horizontal loading and unloading tilting mechanism 39 by the transfer trolley 40. The operator controls the loading and unloading tilting mechanism 39 from the horizontal position to the vertical position via the control cabinet. The operator enters the middle layer of the frame via the ladder 37, installs the lifting device on the material basket 41, and operates the overhead crane to lift the material basket 41.

[0106] The material basket 41 is first hoisted into the cleaning station and placed in the cleaning tank 1 for cleaning operations such as spraying, bubbling, and ultrasonic cleaning to remove most of the chromium shavings. The spray pump pressurizes deionized water and introduces it into the cleaning tank through the spray pipe to rinse the main component 4. The gantry hook can be operated to raise and lower the material basket 41 in the tank, so that all parts of the main component 4 are thoroughly rinsed. The external heated water tank 14 heats the deionized water and injects it into the station, so that the main component 4 is completely submerged. Compressed air from the external system is injected from the bubbling pipe 8 at the bottom of the tank to achieve the bubbling function. The ultrasonic vibrating plate 6 on the side of the tank and the ultrasonic vibrating plate 9 at the bottom generate ultrasound to ultrasonically disturb the inner and outer surfaces of the main component 4.

[0107] After the cleaning process is completed, the main component 4 is hoisted into the spray drying station for preliminary spray drying. This step removes most of the residual water from the main component 4, solving the problems of excessive residual moisture leading to excessive drying time and excessive solid residue during the drying process. Compressed air enters the tank through the spray inlet pipe 86, spraying away residual water and trace amounts of chromium shavings from the main component 4. The hoist hook can be raised and lowered to move the material basket 41 up and down within the tank, ensuring that all parts of the main component 4 are thoroughly sprayed. Alternatively, the main component 4 can be manually sprayed using an air gun.

[0108] After completing the blowing process, the main component 4 is hoisted into the drying station for drying. The drying tank 3, hot air filter box 94, hot air circulation pump 19, and heating pack 18 constitute a hot air circulation and filtration loop. Hot air from the top of the drying tank is heated by the hot air circulation pump 19 and then enters from the bottom of the drying tank, where it is evenly dried by the hot air plate 97. In this position, residual trace amounts of chromium shavings and moisture are removed, and the cleanliness of the main component 4 meets the standards.

[0109] Operators control the operation process by operating the control system according to the prescribed process flow and steps.

[0110] An embodiment of the present invention discloses a method for cleaning chromium shavings from the main components of a fuel assembly, comprising the following steps:

[0111] Step 1: Place the workpiece to be cleaned in the material basket, push it into the loading and unloading tilting mechanism using a transfer trolley, tilt the material basket to a vertical position, install the lifting device, and use an overhead crane to lift it.

[0112] Step 2: Hoist the main component from the loading and unloading station to the cleaning station in the cleaning tank; the hot water in the cleaning tank is filtered in two stages and sprayed onto the main component for 5-10 minutes, ultrasonic cleaning for 30-40 minutes, and bubble cleaning for 5-10 minutes. The ultrasonic and bubble cleaning cycles are repeated at least twice; the cleaning water must be Grade A water with a temperature between 70-90℃.

[0113] The cleaning water generated during cleaning is discharged from the cleaning tank and then filtered twice before being returned to the cleaning tank for reuse.

[0114] Step 3: Hoist the main component from the cleaning station to the blowing station; raise and lower the material basket so that the blowing pipe can fully blow the main component to all parts. After raising and lowering several times, observe the residual moisture inside the main component and select to use an air gun for fixed-point blowing.

[0115] Step 4: Hoist the main component from the blowing station to the drying station; dry with hot air for 30-40 minutes at a temperature of 70-90℃;

[0116] Step 5: The main component is hoisted from the drying station to the loading and unloading station; the material basket lifting device is disassembled, the loading and unloading tilting mechanism is operated to a horizontal position, the material basket is pulled out to the transfer trolley, and the material basket is disassembled to take out the main component.

[0117] In one specific embodiment, the operating steps and process parameters are as follows:

[0118] (1) Loading. Place the main component to be cleaned into the material basket 41 and push it into the loading and unloading tilting mechanism using a transfer trolley. Tilt the material basket 41 to a vertical position, install the lifting device, and use a crane to lift it.

[0119] (2) Cleaning of main components. The main components are hoisted from the loading and unloading station to the cleaning station. Spray cleaning for 5 minutes, ultrasonic cleaning for 30 minutes, and bubbling cleaning for 5 minutes are performed. The ultrasonic and bubbling cleaning cycles are repeated twice. The cleaning water must be Grade A water with a temperature between 70 and 90°C.

[0120] (3) Main component blowing. Hoist the main component from the cleaning station to the blowing station. Raise the material basket 41 so that the blowing pipe can fully blow all parts of the main component. After raising and lowering 4 times, observe the residual moisture inside the main component. If necessary, use an air gun for fixed-point blowing.

[0121] (4) Drying the main components. Hoist the main components from the blowing station to the drying station. Dry with hot air for 30 minutes. The required drying temperature is 70-90℃.

[0122] (5) Unloading. Hoist the main component from the drying station to the loading and unloading station. Disassemble the basket lifting device, operate the loading and unloading tilting mechanism to a horizontal position, pull out the basket 41 to the transfer trolley, disassemble the basket 41 and take out the main component.

[0123] The device can process two main components simultaneously at each of its cleaning, blowing, and drying stations without interference. Once a main component leaves one station and is transferred to the next, the previous station can receive a new main component. Therefore, the device can simultaneously receive up to six main components for different processes.

[0124] The above description of the embodiments is only for the purpose of helping to understand the method and core ideas of the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

[0125] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An apparatus for cleaning chromium-deposited parts of fuel assembly main components, characterized in that, include: The cleaning tank, blowing tank and drying tank are arranged side by side at equal intervals. All three tanks are vertical structures and each has at least two processing positions inside. The upper part of the cleaning tank is connected to the heating water tank via a spray water supply pipe. The top of the heating water tank is connected to the upper limit of the water level in the cleaning tank via a return water pipe. A first water pipe and a second water pipe are installed on the side wall of the heating water tank. The drain pipe at the bottom of the cleaning tank is connected to the spray water supply pipe of the cleaning tank through a circulation pipeline. A circulation pump, a primary filter, and a secondary filter are connected in sequence on the circulation pipeline. The first water pipe is connected to the inlet side of the primary filter in the circulation pipeline. The second water pipe is connected to the outlet side of the secondary filter in the circulation pipeline. A spray pipe is installed at the upper end of the interior of the cleaning tank; symmetrical side ultrasonic transducers are installed below the spray pipe, and a bottom ultrasonic transducer is installed at the bottom of the tank; a cleaning tank guide frame is also installed inside the tank to guide the material basket to move vertically up and down inside the tank; a bubble tube is installed below the cleaning tank guide frame. The drying tank is connected to an air collection box, which is connected to an air outlet pipe, a hot air filter box, a hot air circulation pump, and a heating pack. The other end of the heating pack is connected to the tank body of the drying tank. The left side of the cleaning tank is equipped with a loading and unloading tilting mechanism, which switches the main component between vertical and horizontal positions to serve as the loading and unloading position for the device; the frame is the skeleton of the entire device and is divided into three layers; the control cabinet is located on the far left of the frame and integrates the control system of the entire device; the traveling system is located on the top layer of the frame and can move between different tank positions and the loading and unloading tilting mechanism to transfer the main component between different tanks.

2. The apparatus for cleaning chromium deposits from the main components of a fuel assembly according to claim 1, characterized in that, The side-mounted ultrasonic transducer plate has two rows of ultrasonic transducers arranged at equal intervals inside, with 18 to 25 ultrasonic transducers in each row and an interval of 4 to 6 cm; the two rows of ultrasonic transducers are spaced 10 to 16 cm apart, so that they are exactly aligned with the two main components inside the material basket. Five to ten ultrasonic transducers are arranged at equal intervals inside the bottom ultrasonic transducer plate, directly facing the bottom of the main component inside the basket.

3. The apparatus for cleaning chromium deposits from the main components of a fuel assembly according to claim 1, characterized in that, A pair of limiting plates are provided at the top of the blowing trough; two sets of blowing pipes are provided on the upper part of the side wall of the blowing trough, and the blowing pipes are located above the material basket when the material basket is placed in the trough. The spray nozzles of the spray pipe are arranged in three layers at equal intervals, with 8 to 16 nozzles in each layer; a spray pipe guide frame is installed in the spray trough to guide the material basket to move vertically up and down in the trough. A ring of dispersed jet outlets is set at the bottom of the tank, and the gas in the tank is collected and discharged along a fixed pipeline.

4. The apparatus for cleaning chromium deposits from the main components of a fuel assembly according to claim 1, characterized in that, A pair of drying tank limiting plates are installed at the top of the drying tank, and a heat insulation layer is wrapped around the outside of the tank body. The tank is equipped with an air collection layer, and multiple air collection ports are set at the top and bottom of the air collection layer to collect the hot air in the tank into the air collection layer, and then the gas in the tank is discharged through the air collection box. A drying trough guide frame is installed inside the trough to guide the material basket to move vertically up and down.

5. The apparatus for cleaning chromium deposits from the main components of a fuel assembly according to claim 1, characterized in that, A set of hot air plates is installed below the air collection box. When the material basket is placed in the trough, the hot air plates can wrap around the main component. The set of hot air plates consists of two side hot air plates and one bottom hot air plate. Each hot air plate has evenly distributed air outlet holes on its inner side. The hot air plates are connected by connecting pipes. Hot air enters from the air inlet of the hot air plate and is guided by the hot air plate. It is then blown from the air outlet to various parts of the main component to achieve a uniform drying effect.

6. The apparatus for cleaning chromium deposits from the main components of a fuel assembly according to claim 1, characterized in that, The loading and unloading tilting mechanism and the transfer trolley work together to realize the transfer of the main components; The main body of the loading and unloading tilting mechanism is the tilting mechanism frame. When the tilting mechanism frame is placed horizontally, a pair of material basket guide rollers are set at its bottom. The tilting mechanism frame is driven by the tilting mechanism drive motor, and the tilting is achieved through the tilting mechanism transmission gear. The top of the transfer trolley is equipped with a row of rollers, and a stop bar is installed above the end rollers. One end of the stop bar is connected to the frame of the transfer trolley, and the other end can be flipped freely. When the material basket is loaded, it closes to prevent the material basket from slipping.

7. The apparatus for cleaning chromium deposits from the main components of a fuel assembly according to claim 1, characterized in that, A pair of guide rails are horizontally mounted on the upper layer of the frame, and the trolley moves on the guide rails; The trolley is equipped with a main support; the hoist motor is installed on the main support; the hook is connected to the bottom of the hoist motor, and the hoist motor drives the hook to rise or fall in the middle space of the frame; the mobile motor is installed on the trolley to drive the trolley to move laterally on the guide rail, and the trolley can be controlled by the trolley controller. The bottom layer of the frame is equipped with a control cabinet, a loading and unloading tilting mechanism, a cleaning tank, a blowing tank, and a drying tank; The middle layer of the rack is the personnel operation area.

8. The apparatus for cleaning chromium deposits from the main components of a fuel assembly according to claim 7, characterized in that, The hook suspends the basket lifting device. The top of the basket lifting device is a lifting plate, and below the lifting plate is a lifting beam, which can be placed on the limiting plates of the three troughs to suspend the basket in the trough. The lifting beam is connected to the lifting rod below the lifting beam. The bottom of the rod is forked with two holes. After the lifting plate of the basket is inserted into the fork, the buckle is inserted and the retaining ring is placed on the buckle to complete the connection between the basket lifting device and the basket. Conversely, the lifting device can be removed from the basket.

9. The apparatus for cleaning chromium deposits from the main components of a fuel assembly according to claim 8, characterized in that, The material basket includes: Material basket tooling rack The basket tooling frame has three pairs of clamping plates arranged equidistantly along its length. Each pair of clamping plates consists of an upper clamping plate, a lower clamping plate, and a pair of knurled handle screws. The lower clamping plate is fixed to the material basket fixture frame, and the upper clamping plate is fixed to the lower clamping plate by knurled handle screws. The tightness of the knurled handle screws can be adjusted manually to fix the position of the main component. A bottom clamping plate is fixed to the bottom of the material basket. The bottom clamping plate has a square hole with half depth to lock the bottom of the main component. A top baffle is installed on the top of the material basket fixture frame. It has evenly distributed round holes to block some foreign objects while keeping the water and air flow unobstructed. A hanging plate is set at the center of the top of the material basket and connected to the material basket lifting device.

10. A method for cleaning chromium-deposited main components of a fuel assembly, characterized in that, Includes the following steps: Step 1: Place the workpiece to be cleaned in the material basket, push it into the loading and unloading tilting mechanism using a transfer trolley, tilt the material basket to a vertical position, install the lifting device, and use an overhead crane to lift it. Step 2: Hoist the main component from the loading and unloading station to the cleaning station in the cleaning tank; the hot water in the cleaning tank is filtered in two stages and sprayed onto the main component for 5-10 minutes, ultrasonic cleaning for 30-40 minutes, and bubble cleaning for 5-10 minutes. The ultrasonic and bubble cleaning cycles are repeated at least twice; the cleaning water must be Grade A water with a temperature between 70-90℃. The cleaning water generated during cleaning is discharged from the cleaning tank and then filtered twice before being returned to the cleaning tank for reuse. Step 3: Hoist the main component from the cleaning station to the blowing station; raise and lower the material basket so that the blowing pipe can fully blow the main component to all parts. After raising and lowering several times, observe the residual moisture inside the main component and select to use an air gun for fixed-point blowing. Step 4: Hoist the main component from the blowing station to the drying station; dry with hot air for 30-40 minutes at a temperature of 70-90℃; Step 5: The main component is hoisted from the drying station to the loading and unloading station; the material basket lifting device is disassembled, the loading and unloading tilting mechanism is operated to a horizontal position, the material basket is pulled out to the transfer trolley, and the material basket is disassembled to take out the main component.

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