An operating method of a device for pressing a rod lower end plug

Abstract

The present invention discloses an operating method of a device for pressing a lower end plug of a rod, comprising a plug seat and a guide sleeve, wherein the plug seat is arranged in a sleeve body. The end plug seat comprises a plug seat subjected to force on the side surface and a plug seat subjected to force on the top end. The guide sleeve comprises a short guide sleeve and a long guide sleeve. The beneficial effect of the present invention is that when the present invention is used to produce rods, the lower end plug can be easily removed, and at the same time, no scratches occur on the surface of the product, thereby improving the appearance quality of the product, and meeting the product pressing process requirements, thereby achieving the purpose of improving product quality.

Description

Technical Field

[0001] The invention belongs to the technical field of nuclear fuel element preparation, and in particular relates to an operating method of a device for pressing a lower end plug of a rod. Background Art

[0002] The plugging machine is an important device for pressing the lower end plug into the cladding tube before the fuel rod or rod is welded by electron beam or non-melting and inert gas tungsten arc welding (TIG welding). The plugging process directly affects the subsequent welding quality: too large a gap is likely to cause incomplete welding; uneven gaps are likely to cause uneven welding; deflection of the plug will lead to subsequent welding failures, and even cannot be repaired and must be scrapped. The traditional plugging mechanism can only achieve the pressing of one specification of lower end plug.

[0003] During the production process of the rod, the lower end plug needs to be pressed into the cladding tube, and then electron beam or non-melting inert gas tungsten arc welding (TIG welding) is performed. The plug press is an important equipment for pressing the lower end plug into the cladding tube. The plug pressing process directly affects the subsequent welding quality: too large a gap is likely to cause incomplete welding; uneven gaps are likely to cause uneven welding; deflection of the plug will lead to subsequent welding failures, and even cannot be repaired and must be scrapped. Traditional plug presses can only achieve the pressing of one specification of lower end plugs.

[0004] During the production process, the following situations often occur after the plugging is completed: the plug seat and the lower end plug are not easy to separate; there is an indentation on the top of the lower end plug; there are scratches on the surface of the lower end plug. Summary of the invention

[0005] The purpose of the present invention is to provide a device for pressing the lower end plug of a rod, which can effectively solve the problems existing in the prior art that the plug seat and the lower end plug are not easy to separate, there are indentations on the top of the lower end plug, and there are scratches on the surface of the lower end plug.

[0006] The technical solution of the present invention is as follows: an operating method of a device for pressing a plug at the lower end of a rod, comprising a plug seat and a guide sleeve, wherein the plug seat is arranged in a sleeve body;

[0007] The plug seat includes two types: a plug seat with side surface force or a plug seat with top force, and the guide sleeve includes two types: a short guide sleeve or a long guide sleeve;

[0008] The plug seat with side surface force comprises a first plug seat, a first plug head, a first through hole, a second through hole and a through hole, wherein the first plug seat is a stepped cylindrical structure, a portion with a larger diameter is provided with a first through hole, a portion with a smaller diameter is provided with a second through hole, the cylindrical first plug head is arranged in the first through hole, a tapered hole matching the shape of the lower end plug head is provided in the middle of the first plug head, the tapered hole is communicated with the through hole, and the through hole is communicated with the second through hole;

[0009] The plug seat subjected to top force comprises a second plug seat, a second plug head, a third through hole, a fourth through hole, a fifth through hole and a groove, wherein the second plug seat is a stepped cylindrical structure, and through holes of different diameters are sequentially opened inside the second plug seat, specifically comprising a third through hole, a fourth through hole and a fifth through hole, wherein the aperture of the third through hole is larger than the aperture of the fourth through hole, and the aperture of the fourth through hole is larger than the aperture of the fifth through hole, and the second plug head is arranged in the fourth through hole, and the end of the second plug head is provided with a groove matching the top of the lower end plug;

[0010] The material of the first plug seat and the second plug seat is AISI 304L, and the material of the first plug head and the second plug head is polyethylene;

[0011] The short guide sleeve comprises a short sleeve body, an end plug hole and an exhaust hole, wherein the cylindrical short sleeve body is provided with an end plug hole, the end plug hole is connected with the plug seat hole, the diameter of the plug seat hole matches the diameter of the plug seat, and the short sleeve body is also provided with an exhaust hole connected with the end plug hole;

[0012] The long guide sleeve comprises a long sleeve body, an observation hole, an end plug through hole, a vent hole and a long groove, wherein the long sleeve body is provided with an end plug through hole, the end plug through hole is connected with the plug seat hole, the diameter of the plug seat hole matches the diameter of the plug seat, the long sleeve body is also provided with a vent hole connected with the end plug through hole, an observation hole is provided in the middle position of the long sleeve body, and a long groove is provided at the intersection of the observation hole and the end plug through hole,

[0013] During the plugging process, the plug head and the plug seat are used in conjunction with each other, the plug head contacts the lower end plug, the plug seat does not contact the lower end plug, and the force point of the lower end plug is the side surface of the lower end plug or the top of the lower end plug;

[0014] When using the short guide sleeve, use it in conjunction with the supporting mechanism; when using the long guide sleeve, remove the supporting mechanism and do not use it anymore.

[0015] The beneficial effect of the present invention is that when the present invention is used to produce rods, the lower end plug can be easily removed, and no scratches occur on the product surface, thereby improving the appearance quality of the product, meeting the product plugging process requirements, and achieving the purpose of improving product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the principle of the existing plugging machine;

[0017] Figure 2 It is a detailed schematic diagram of the lower end plug and the plug seat;

[0018] Figure 3 A schematic diagram of a plug seat with force applied to the side surface of the lower end plug;

[0019] Figure 4 A schematic diagram of a plug seat with force applied to the top end of the lower end plug;

[0020] Figure 5 It is a schematic diagram of a short guide sleeve;

[0021] Figure 6 It is a schematic diagram of a long guide sleeve;

[0022] Figure 7 Schematic diagram of the cooperation between the plug seat and the short guide sleeve on the side surface of the lower end plug;

[0023] Figure 8 Schematic diagram of the cooperation between the plug seat bearing force at the top end of the lower end plug and the short guide sleeve;

[0024] Fig. 9 Schematic diagram of the cooperation between the plug seat and the long guide sleeve on the side surface of the lower end plug;

[0025] Fig.10 Schematic diagram of the cooperation between the plug seat bearing force at the top end of the lower end plug and the long guide sleeve.

[0026] In the figure: 1 cladding tube; 2 clamping mechanism; 3 supporting mechanism; 4 lower end plug; 5 plug seat; 6 plug cylinder; 7 control box, 11 lower end plug, 12 first plug seat, 13 first plug head, 14 first through hole, 15 second through hole, 16 through hole, 22 second plug seat, 23 second plug head, 24 third through hole, 25 fourth through hole, 26 fifth through hole, 27 groove, 31 short sleeve, 32 end plug hole, 33 exhaust hole, 41 long sleeve, 42 observation hole, 43 end plug through hole, 44 ventilation hole, 45 long groove. DETAILED DESCRIPTION

[0027] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0028] like Figure 1 As shown, the principle of the existing plugging machine is as follows: the cladding tube 1 is fixed by the clamping mechanism 2 and the supporting mechanism 3 to prevent the cladding tube 1 from moving; the plug seat 5 is used to position the lower end plug 4 to limit the axial and radial displacement of the lower end plug 4; the plug seat 5 is pushed by the cylinder movement of the plugging 6 to move the lower end plug 4, and finally the plugging effect is achieved; the entire process can be controlled by the buttons on the control box 7.

[0029] Details of the lower end plug and plug seat are as follows Figure 2 As shown, it can be seen that during the plugging process, a negative pressure area is formed between the plug seat and the lower end plug. The original plug seat was made of stainless steel. During the plugging process, the plug seat and the lower end plug formed a negative pressure area. After the plugging is completed, the lower end plug is not easy to remove from the plug seat. At the same time, because the material in contact with the lower end plug is stainless steel, scratches are easily formed on the surface of the lower end plug when the lower end plug is removed. After long-term plugging, the inner surface of the plug seat is easily deformed, resulting in an increase in the inner hole. During the plugging process, the force point of the lower end plug becomes the top of the lower end plug, resulting in an indentation on the top of the lower end plug.

[0030] After analysis and summary, it is believed that the following areas need to be improved: (1) Remove the negative pressure area formed between the plug seat and the lower end plug during the plugging process so that the lower end plug can be easily removed from the plug seat; (2) Change the material in contact with the lower end plug and the cladding tube to non-metallic materials so that no scratches or indentations will be generated during the plugging process; (3) Improve the alignment of the plugging machine and the clamping mechanism so that no deviation will occur during the plugging process.

[0031] When designing a plug seat, the following points need to be considered:

[0032] (1) It needs to be used in conjunction with the original equipment and its dimensions are determined;

[0033] (2) Do not create a negative pressure area during the tamponade process and pay attention to ventilation;

[0034] (3) Minimize the scratches on the surface of the lower plug during the plugging process;

[0035] (4) The stress point of the lower end plug during the plugging process;

[0036] (5) It is necessary to improve the alignment between the plugging machine and the clamping mechanism so that they do not tilt during the plugging process.

[0037] In order to improve the alignment between the clamping mechanism and the plug seat, the effect of the plug seat alone is not obvious, so a guide sleeve can be added to the plug seat. The material used is polyethylene, and the size is slightly larger than the outer diameter of the cladding tube. This can not only improve the alignment between the clamping mechanism and the plug seat, but also reduce scratches on the surface of the cladding tube.

[0038] like Figure 3-10 As shown, a device for pressing the lower end plug of a rod comprises a plug seat and a guide sleeve, wherein the plug seat is arranged in a sleeve body, wherein the end plug seat comprises a plug seat subjected to force on the side surface and a plug seat subjected to force on the top end, and the guide sleeve comprises a short guide sleeve and a long guide sleeve.

[0039] like Figure 3 As shown, the plug seat subjected to force on the side surface includes a first plug seat 12, a first plug head 13, a first through hole 14, a second through hole 15 and a through hole 16, wherein the first plug seat 12 is a stepped cylindrical structure, a portion with a larger diameter is provided with the first through hole 14, a portion with a smaller diameter is provided with the second through hole 15, the cylindrical first plug head 13 is arranged in the first through hole 14, a conical hole matching the shape of the head of the lower end plug 11 is provided in the middle of the first plug head 13, the conical hole is communicated with the through hole 16, and the through hole 16 is communicated with the second through hole 15.

[0040] like Figure 4As shown, the plug seat subjected to force at the top end includes a second plug seat 22, a second plug head 23, a third through hole 24, a fourth through hole 25, a fifth through hole 26 and a groove 27, wherein the second plug seat 22 is a stepped cylindrical structure, and through holes of different diameters are sequentially opened inside, specifically including a third through hole 24, a fourth through hole 25 and a fifth through hole 26, wherein the aperture of the third through hole 24 is larger than the aperture of the fourth through hole 25, and the aperture of the fourth through hole 25 is larger than the aperture of the fifth through hole 26, and the second plug head 23 is arranged in the fourth through hole 25, and the end of the second plug head 23 is provided with a groove 27 matching the top of the lower end plug 11.

[0041] The first plug seat 12 and the second plug seat 22 are made of AISI 304L, and the first plug head 13 and the second plug head 23 are made of polyethylene.

[0042] like Figure 5 As shown, the short guide sleeve includes a short sleeve body 31, an end plug hole 32, and an exhaust hole 33, wherein the cylindrical short sleeve body 31 is provided with an end plug hole 32, the end plug hole 32 is connected to the plug seat hole, the aperture of the plug seat hole matches the diameter of the plug seat, and the short sleeve body 31 is also provided with an exhaust hole 33 connected to the end plug hole 32.

[0043] like Figure 6 As shown, the long guide sleeve includes a long sleeve body 41, an observation hole 42, an end plug through hole 43, a vent 44 and a long groove 45, wherein the long sleeve body 41 has an end plug through hole 43, the end plug through hole 43 is connected to the plug seat hole, the aperture of the plug seat hole matches the diameter of the plug seat, the long sleeve body 41 also has a vent 44 connected to the end plug through hole 43, an observation hole 42 is opened in the middle position of the long sleeve body 41, and a long groove 45 is opened at the intersection of the observation hole 42 and the end plug through hole 43.

[0044] In order to reduce the scratches on the surface of the lower end plug during the plugging process, the material in contact with the lower end plug is changed to polyethylene; however, if the plug seat is made of polyethylene, it is easy to deform due to the plugging force and needs to be replaced frequently. Therefore, it is designed to be used in conjunction with the plug head and the plug seat, with the plug head in contact with the lower end plug; the plug seat does not contact the lower end plug, and the material is AISI 304L. During the plugging process, the lower end plug can have two force points, one is the side surface of the lower end plug, which has a large force area; the other is the top of the lower end plug, which can make the force on the lower end plug uniform.

[0045] like Figure 1 As shown, the support mechanism 3 can improve the alignment between the clamping mechanism and the plug seat to a certain extent. In the design process, the size of the entire space needs to be considered for practical use. To this end, the present invention uses two types of long and short guide sleeves, both made of polyethylene. When using the short guide sleeve, it is used in conjunction with the support mechanism, and the short guide sleeve will not interfere with the support mechanism; when using the long guide sleeve, the support mechanism is removed and no longer used.

[0046] The present invention adopts two sets of plug seats and two kinds of guide sleeves, see Figure 7 to Figure 10 .

[0047] The practical effects of the present invention are as follows:

[0048] In actual production, it was found that after replacing the plug seat and pressing the plug, the lower end plug can be easily removed from the plug seat, and there are no scratches on the surface of the lower end plug; after using the long guide sleeve, the centering effect is better, the weld is more uniform, and there is no deviation.

Claims

1. A device for plugging the lower end of a pressing rod, characterized in that: It comprises a plug seat and a guide sleeve, wherein the plug seat is arranged in the sleeve body; The plug seat includes two types: a plug seat with side surface force or a plug seat with top force, and the guide sleeve includes two types: a short guide sleeve or a long guide sleeve; The plug seat with side surface force comprises a first plug seat, a first plug head, a first through hole, a second through hole and a through hole, wherein the first plug seat is a stepped cylindrical structure, a portion with a larger diameter is provided with a first through hole, a portion with a smaller diameter is provided with a second through hole, the cylindrical first plug head is arranged in the first through hole, a tapered hole matching the shape of the lower end plug head is provided in the middle of the first plug head, the tapered hole is communicated with the through hole, and the through hole is communicated with the second through hole; The plug seat subjected to top force comprises a second plug seat, a second plug head, a third through hole, a fourth through hole, a fifth through hole and a groove, wherein the second plug seat is a stepped cylindrical structure, and through holes of different diameters are sequentially opened inside the second plug seat, specifically comprising a third through hole, a fourth through hole and a fifth through hole, wherein the aperture of the third through hole is larger than the aperture of the fourth through hole, and the aperture of the fourth through hole is larger than the aperture of the fifth through hole, and the second plug head is arranged in the fourth through hole, and the end of the second plug head is provided with a groove matching the top of the lower end plug; The material of the first plug seat and the second plug seat is AISI 304L, and the material of the first plug head and the second plug head is polyethylene; The short guide sleeve comprises a short sleeve body, an end plug hole and an exhaust hole, wherein the cylindrical short sleeve body is provided with an end plug hole, the end plug hole is connected with the plug seat hole, the diameter of the plug seat hole matches the diameter of the plug seat, and the short sleeve body is also provided with an exhaust hole connected with the end plug hole; The long guide sleeve comprises a long sleeve body, an observation hole, an end plug through hole, a vent and a long groove, wherein an end plug through hole is opened in the long sleeve body, the end plug through hole is connected with the plug seat hole, the aperture of the plug seat hole matches the diameter of the plug seat, the long sleeve body is also provided with a vent connected with the end plug through hole, an observation hole is opened in the middle position of the long sleeve body, and a long groove is opened at the intersection of the observation hole and the end plug through hole.

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