An automatic retractable unloading device for uranium dioxide hydrofluorination process

Abstract

An automatically retractable unloading device for use in a uranium dioxide hydrofluorination process belongs to the technical field of uranium conversion production equipment. The present invention is designed to improve the positioning and connection accuracy between the unloading port and the feeding port of a storage container during the unloading process of uranium dioxide materials, and to avoid the leakage of radioactive dust and hydrogen fluoride. The present invention makes technical innovations on the traditional manual unloading mechanism, and designs a unloading device with a retractable mechanism and dynamic sealing. The retractable mechanism is mainly composed of an inner tube, an outer tube, a packing gland, and a sealing packing. The inner tube and the outer tube form a packing bin, and the middle gap is filled with sealing packing. The upper end is compressed by a packing gland. The automatically retractable unloading device of the present invention can realize automatic docking and buffering, improve work efficiency, and reduce the level of personnel exposure. The application of dynamic sealing reduces the risk of leakage of radioactive dust.

Description

Technical Field

[0001] The invention relates to an automatic telescopic unloading device, belonging to the technical field of uranium conversion production equipment. Background Art

[0002] In my country's uranium conversion production process, uranium dioxide reacts with hydrogen fluoride in a baffled bed to produce uranium tetrafluoride. During the entire process, in order to increase the absorption rate of uranium dioxide to hydrogen fluoride in the tail gas, the feed and discharge of uranium dioxide in the system must be relatively balanced. The material moves from top to bottom through the baffled bed, enters the unloading screw conveyor through the temporary storage hopper, and is quantitatively transported to the storage container in the unloading chamber. An electric trolley with an electronic scale is installed under the storage container. The unloading and transportation of the reacted material is achieved through the periodic reciprocating movement of the electric trolley.

[0003] Among them, because hydrogen fluoride is contained in the uranium tetrafluoride material, and the unloading port of the screw conveyor and the storage container need to be frequently docked, in order to ensure that the unloading port and the storage container are accurately positioned and connected, avoid the leakage of radioactive dust and hydrogen fluoride, and reduce manual assembly time, it is necessary to design an automatically retractable unloading device that is resistant to hydrogen fluoride corrosion.

[0004] At present, the device that can achieve telescopic is mainly corrugated hose, which is made of carbon steel welded pipe after corrugation. It can be used to compensate for the mutual displacement of pipelines or machines, and has good vibration reduction and flexibility. However, due to its thin wall and poor corrosion resistance to hydrogen fluoride, the corrugated hose will crack and break during use.

[0005] Based on the above situation, it is urgent to carry out research on the automatic retractable unloading device for the uranium dioxide hydrofluorination process, improve the existing production system, ensure the stability and efficiency of the unloading process, reduce the generation of radioactive dust from the source, and ensure the operation of uranium conversion facilities and environmental safety. Summary of the invention

[0006] The present invention aims to improve the positioning connection accuracy of the discharge port and the storage container feed port during the uranium dioxide material discharge process, and to avoid the leakage of radioactive dust and hydrogen fluoride. A brief overview of the present invention is given below to provide a basic understanding of certain aspects of the present invention. It should be understood that this overview is not an exhaustive overview of the present invention. It is not intended to determine the key or important parts of the present invention, nor is it intended to limit the scope of the present invention.

[0007] The present invention makes technical innovation on the traditional manual unloading mechanism and designs a unloading device with a telescopic mechanism and dynamic sealing. The telescopic mechanism has the characteristics of simple structure, convenient operation, low operation and maintenance cost, safety and reliability;

[0008] The actuator is mainly composed of an electric push cylinder and a connecting rod mechanism. The electric push cylinder and the connecting rod fulcrum are fixed on the frame. The push rod of the electric push cylinder is connected to the connecting rod through a hinge structure, and the other end is fixed to the telescopic pipe by bolts. When the electric push cylinder moves forward and backward, the lever principle is used to drive the connecting rod to realize the up and down movement of the telescopic pipe.

[0009] The telescopic mechanism is mainly composed of an inner tube, an outer tube, a packing gland, and a sealing packing. The inner tube and the outer tube form a packing bin, the middle gap is filled with a sealing packing, and the upper end is compressed by the packing gland. When the telescopic mechanism moves, the inner tube does not move, and the outer tube moves up and down driven by the connecting rod. The sealing packing can achieve dynamic sealing to prevent the leakage of material dust.

[0010] In order to avoid the flange rigid connection damaging the electric push cylinder during the pipeline movement, a guide buffer device is set up, which is mainly composed of a positioning flange, a guide rod, and a buffer mechanism. The buffer mechanism is composed of a spring, one end of which is connected to a sealing flange and the other end is connected to a positioning flange. The positioning flange is welded to the guide rod. When the telescopic pipeline reaches the limit point, the spring can be stretched to achieve a soft seal between the discharge port and the 210L container. The guide rod can ensure that the movement direction of the telescopic mechanism is always in the vertical direction to avoid dislocation.

[0011] The technical solution of the present invention:

[0012] An automatically retractable unloading device for uranium dioxide hydrofluorination process comprises an inner unloading tube, an electric knife gate valve arranged on the inner unloading tube and a frame for installing the device, a retractable mechanism is slidably mounted on the outer wall of the inner unloading tube, a guide buffer device is arranged on the retractable mechanism, an actuator is arranged on the frame, an output end of the actuator is connected with the retractable mechanism, and the actuator can control the retractable mechanism to slide up and down along the inner unloading tube.

[0013] Preferably: the actuator includes an electric push cylinder and a connecting rod, the electric push cylinder is mounted on the frame, the middle part of the connecting rod is hinged to the frame, one end of the connecting rod is hinged to the output end of the electric push cylinder, and the other end of the connecting rod is connected to the telescopic mechanism.

[0014] Preferably: the telescopic mechanism includes a sealing packing, an outer discharge tube, a sealing flange and a packing gland; the outer discharge tube is slidably arranged on the inner discharge tube; a flat welding flange is arranged on the top of the outer discharge tube; the bottom of the outer discharge tube is connected to the sealing flange; a sealing packing is arranged between the outer discharge tube and the inner discharge tube; the packing gland is connected to the flat welding flange and compresses the sealing packing.

[0015] Preferably: the guide buffer device includes a positioning flange, a buffer spring, a guide rod and a guide plate, the guide plate is fixedly set on the unloading inner tube, the positioning flange is slidably set on the outer wall of the unloading outer tube, one end of the guide rod is connected to the positioning flange, the other end of the guide rod passes through the guide plate and is limited by a nut, the two ends of the buffer spring are respectively connected to the positioning flange and the sealing flange, and the number of guide rods and buffer springs is at least 2.

[0016] Preferably, the number of the guide rods and buffer springs is four.

[0017] The present invention has the following beneficial effects:

[0018] The present invention provides an automatic retractable unloading device for uranium dioxide hydrofluorination process, which has the following beneficial effects:

[0019] 1 The automatic retractable unloading device designed by the present invention improves and perfects the existing device, can realize automatic docking and buffering, improves work efficiency, and reduces the exposure level of personnel;

[0020] 2 The automatic retractable unloading device designed in the present invention improves the disadvantage of short service life of the corrugated hose, and the application of dynamic seal reduces the risk of leakage of radioactive dust;

[0021] 3 The automatic retractable unloading device designed in the present invention has a simple structure, is convenient for daily maintenance, and improves the economy of process operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the structure of the execution structure;

[0023] Figure 2 It is a schematic diagram of the structure of an automatic telescopic unloading device used in the uranium dioxide hydrofluorination process;

[0024] Figure 3 It is a structural schematic diagram of the telescopic mechanism and the guide buffer device;

[0025] Figure 4 yes Figure 3 Cross-sectional bottom view.

[0026] In the figure, 1-discharging inner tube, 2-sealing packing, 3-discharging outer tube, 4-positioning flange, 5-buffer spring, 6-sealing flange, 7-210L container, 8-electric knife gate valve, 9-guide rod, 10-packing gland, 11-electric push cylinder, 12-connecting rod, 13-guide plate. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is described below by the specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0028] The connection mentioned in the present invention is divided into fixed connection and detachable connection. The fixed connection is a non-detachable connection including but not limited to conventional fixed connection methods such as folding connection, rivet connection, bonding connection and welding connection. The detachable connection includes but not limited to conventional detachable methods such as threaded connection, snap connection, pin connection and hinge connection. When the specific connection method is not clearly defined, it is assumed that at least one connection method can always be found in the existing connection methods to achieve the function. Those skilled in the art can choose according to their needs. For example: a fixed connection is selected as a welding connection, and a detachable connection is selected as a hinge connection.

[0029] Reference Figures 1 to 3 As shown, this embodiment provides an automatically retractable unloading device for uranium dioxide hydrofluorination process, comprising an unloading inner tube 1, an electric knife gate valve 8 arranged on the unloading inner tube 1 and a frame for installing the equipment, characterized in that a retractable mechanism is slidably mounted on the outer wall of the unloading inner tube 1, a guide buffer device is provided on the retractable mechanism, an actuator is provided on the frame, an output end of the actuator is connected to the retractable mechanism, and the actuator can control the retractable mechanism to slide up and down along the unloading inner tube 1.

[0030] The material of this telescopic device:

[0031] The reaction medium in the tail gas of the hydrofluorination process is hydrogen fluoride and uranium dioxide. Water will be produced during the reaction to generate hydrofluoric acid. Because the working environment is a hydrofluoric acid atmosphere and the working temperature is 200℃~230℃, the automatic telescopic unloading device must be resistant to hydrogen fluoride corrosion. After comprehensive consideration, the parts in the automatic telescopic unloading device that are in contact with the reaction medium are made of Monel400 nickel-copper alloy, and the remaining parts are made of 20# structural steel.

[0032] The actuator includes an electric push cylinder 11 and a connecting rod 12. The electric push cylinder 11 is installed on the frame. The middle part of the connecting rod 12 is hinged to the frame. One end of the connecting rod 12 is hinged to the output end of the electric push cylinder 11, and the other end of the connecting rod 12 is connected to the telescopic mechanism.

[0033] The electric push cylinder 11 can be selected to have a length of 172 mm, a speed of 48 mm / s, and a thrust of 300 N. The connecting rod 12 can be 400 mm in length, and the fulcrum for being hinged with the frame is set at 1 / 3 of the connecting rod. The electric push cylinder 11 drives the telescopic mechanism to move up and down by pushing the connecting rod 12.

[0034] The telescopic mechanism includes a sealing packing 2, a discharge outer tube 3, a sealing flange 6 and a packing gland 10. The discharge outer tube 3 is slidably arranged on the discharge inner tube 1. A flat welding flange is arranged on the top of the discharge outer tube 3. The bottom of the discharge outer tube 3 is connected to the sealing flange 6. A sealing packing 2 is arranged between the discharge outer tube 3 and the discharge inner tube 1. The packing gland 10 is connected to the flat welding flange and presses the sealing packing 2.

[0035] Among them, the inner discharge pipe 1 can be made of N04400 seamless pipe, and the outer discharge pipe is made of 20# seamless pipe. At the same time, it is welded with a DN150 flat welding flange, and the packing gland 10 is made by turning and drilling the corresponding 20# bar. Fill 4×4 sealing packing 2 between the inner discharge pipe 1 and the outer discharge pipe 3. The packing gland 10 is fastened to the DN150 flat welding flange by bolts to compress the sealing packing 2 to ensure dynamic sealing. In order to ensure docking with the flange port of the 210L container 7, the sealing flange is made of 25mm thick 20# plate and is designed with an inner diameter and an outer diameter of

[0036] The guide buffer device includes a positioning flange 4, a buffer spring 5, a guide rod 9 and a guide plate 13. The guide plate 13 is fixedly arranged on the unloading inner tube 1. The positioning flange 4 is slidably arranged on the outer wall of the unloading outer tube 3. One end of the guide rod 9 is connected to the positioning flange 4. The other end of the guide rod 9 passes through the guide plate 13 and is limited by a nut. The two ends of the buffer spring 5 are respectively connected to the positioning flange 4 and the sealing flange 6. The number of guide rods 9 and buffer springs 5 ​​is at least 2. The connecting rod 12 is hinged to the unloading outer tube 3.

[0037] The positioning flange 4 is designed with a 20# flange with an inner diameter and an outer diameter, and is welded on the outer discharge pipe. The guide rod 9 is a long smooth rod, and one end is turned with an M8 thread. The buffer spring 5 is composed of a 4×25×100 spring, and is evenly fixed on the sealing flange 6 with the guide rod. After assembly and operation, the guiding and buffering functions of the telescopic device can be realized.

[0038] Specifically, selecting four guide rods 9 can make the operation of the device safer and more stable.

[0039] Working method:

[0040] In the hydrofluorination process, hydrogen fluoride and uranium dioxide react to generate uranium tetrafluoride, which is discharged from the reaction bed into the unloading device, that is, into the unloading inner tube 1, and is blocked by the electric knife gate valve 8. When unloading is required, the 210L container 7 needs to be moved to the bottom of the unloading inner tube 1, and the electric push cylinder 11 is started. The electric push cylinder 11 pulls the connecting rod 12 to drive the unloading outer tube 3 in the telescopic mechanism to move downward. When the nut on the guide rod 9 abuts against the guide plate 13, the guide rod 9 and the positioning flange 4 reach the limit and stop moving downward. At this time, the sealing flange 6 begins to stretch the buffer spring 5 until the sealing flange 6 and the 210L container 7 flange achieve soft sealing. At this time, the electric push cylinder 11 is closed, and the electric knife gate valve 8 is opened. The uranium tetrafluoride is unloaded from the unloading inner tube 1 into the 210L container 7. After the 210L container 7 is full, the electric knife gate valve 8 is closed, and the electric push cylinder 11 is opened in the reverse direction. The connecting rod 12 drives the unloading outer tube 3 to move upward, and finally the unloading device returns to its original position.

[0041] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0042] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, numerical expressions and numerical values ​​do not limit the scope of the present invention. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be regarded as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0043] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the devices or elements referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention. The directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0044] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0045] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein.

[0046] It should be noted that in the above embodiments, as long as the technical solutions are not contradictory, they can be arranged and combined, and those skilled in the art can exhaust all possibilities based on the mathematical knowledge of arrangement and combination. Therefore, the present invention will no longer describe the technical solutions after arrangement and combination one by one, but it should be understood that the technical solutions after arrangement and combination have been disclosed by the present invention.

[0047] This implementation is only an exemplary description of this patent and does not limit its protection scope. Those skilled in the art may also make partial changes to it, as long as they do not exceed the spirit of this patent, they are all within the protection scope of this patent.

Claims

1. An automatically retractable unloading device for uranium dioxide hydrofluorination process, comprising an unloading inner tube (1), an electric knife gate valve (8) arranged on the unloading inner tube (1) and a frame for mounting the device, characterized in that: A telescopic mechanism is slidably mounted on the outer wall of the discharge inner tube (1), the telescopic mechanism is provided with a guide buffer device, an actuator is provided on the frame, the output end of the actuator is connected to the telescopic mechanism, and the actuator controls the telescopic mechanism to slide up and down along the discharge inner tube (1); The actuator comprises an electric push cylinder (11) and a connecting rod (12), wherein the electric push cylinder (11) is mounted on a frame, the middle portion of the connecting rod (12) is hinged to the frame, one end of the connecting rod (12) is hinged to the output end of the electric push cylinder (11), and the other end of the connecting rod (12) is connected to the telescopic mechanism; The telescopic mechanism comprises a sealing packing (2), a discharge outer tube (3), a sealing flange (6) and a packing gland (10); the discharge outer tube (3) is slidably arranged on the discharge inner tube (1); a flat welding flange is arranged on the top of the discharge outer tube (3); the bottom of the discharge outer tube (3) is connected to the sealing flange (6); a sealing packing (2) is arranged between the discharge outer tube (3) and the discharge inner tube (1); the packing gland (10) is connected to the flat welding flange and compresses the sealing packing (2); The guide buffer device comprises a positioning flange (4), a buffer spring (5), a guide rod (9) and a guide plate (13); the guide plate (13) is fixedly arranged on the discharge inner tube (1); the positioning flange (4) is slidably arranged on the outer wall of the discharge outer tube (3); one end of the guide rod (9) is connected to the positioning flange (4); the other end of the guide rod (9) passes through the guide plate (13) and is limited by a nut; the two ends of the buffer spring (5) are respectively connected to the positioning flange (4) and the sealing flange (6); the number of the guide rod (9) and the buffer spring (5) is at least 2; and the connecting rod (12) is hinged to the discharge outer tube (3).

2. The automatic retractable unloading device for uranium dioxide hydrofluorination process according to claim 1, characterized in that: The number of the guide rods (9) and buffer springs (5) is four.

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