Steam generator secondary side water supply ring with foreign matter interception function

Abstract

The invention discloses a steam generator secondary side water supply ring with a foreign matter interception function, the water supply ring comprises a ring pipe and a J-shaped pipe mounted on the ring pipe, the water supply ring comprises a sleeve, and the sleeve is mounted on the J-shaped pipe; the spray head is mounted at the bottom of the sleeve, a filter hole for intercepting foreign matters is formed in one side of the spray head, and the filter hole is formed in the side, facing the central area of the steam generator, of the spray head, so that thermal shock on a secondary side barrel of the steam generator is avoided; the foreign matter intercepting function can be added to the in-service nuclear power plant steam generator water supply ring, damage of large-size dangerous foreign matter to a heat transfer pipe can be effectively intercepted, and nuclear safety is improved. Due to the design of the direction and arrangement of the filtering holes, unacceptable influences such as thermal shock and overlarge resistance on the in-service steam generator are avoided, and a good foreign matter intercepting effect is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of nuclear power steam generators, and in particular to a secondary side water feed ring of a steam generator with a foreign matter interception function. Background Art

[0002] As an important heat exchange equipment in a pressurized water reactor nuclear power plant, the steam generator can transfer the heat in the primary coolant to the secondary feedwater, so that it can generate saturated steam to supply the secondary power unit. After the steam generator feedwater enters the pipe, it reaches the T-joint and enters the feedwater ring in two directions, and then flows into the secondary side of the steam generator through the J-tubes on the left and right sides.

[0003] Related technology 1: The inner diameter of the inverted J-shaped tube of the steam generator water feed ring of the CPR1000 unit is about 52.5mm. The current structure does not have the ability to intercept foreign matter. There is a risk of foreign matter entering the steam generator tube bundle area, thereby damaging the heat transfer tube and affecting nuclear safety.

[0004] Related Technology 2: The existing new steam generator water feed ring structure design with foreign matter interception function is completed in the equipment design and manufacturing stage; the new steam generator water feed ring has significant differences in structure and thermal performance compared to the original design of the CPR1000 unit steam generator, and is not suitable for use in CPR1000 units in service.

[0005] Related technology three: Currently, an anti-foreign object device structure is added to the feed water ring of the CPR1000 unit. This structure fixes the anti-foreign object device to the J-tube by extrusion deformation. The wall thickness of both is large and it is not easy to deform, making installation difficult. In addition, this fixing method is not reliable, and the turbulent state in the feed water ring can easily induce vibration, which poses a risk of loosening. The holes around the nozzle structure will cause thermal shock to the steam generator cylinder caused by the feed water, causing unacceptable impact on the pressure boundary. The holes in the lower part of the nozzle structure will make it easier for long foreign objects to pass through the anti-foreign object device, reducing the interception effect. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a steam generator secondary water supply ring which can be installed in a narrow space without causing thermal shock fatigue to the secondary side cylinder of the steam generator and has a foreign matter interception function.

[0007] The technical solution adopted by the present invention to solve the technical problem is: a secondary side water supply ring of a steam generator with a foreign body interception function, the water supply ring comprising a ring pipe and a J-shaped pipe installed on the ring pipe, including:

[0008] a sleeve mounted on the J-tube;

[0009] The nozzle is installed at the bottom of the sleeve, and a filter hole for intercepting foreign matter is opened on one side of the nozzle, and the filter hole is opened on the side of the nozzle facing the central area of ​​the steam generator to avoid thermal shock to the secondary side cylinder of the steam generator.

[0010] Further, in the secondary water supply ring of the steam generator with foreign matter interception function, the sleeve preferably includes a circular arc section pipe and a straight section pipe whose one end is matched on the J-shaped pipe;

[0011] The straight section pipe is fixedly or detachably installed at the other end of the arc section pipe, or the arc section pipe and the straight section pipe are an integrated structure;

[0012] At least one plug welding hole is provided on the side of the circular arc segment pipe away from the central area of ​​the steam generator, and the circular arc segment pipe is fixedly connected to the J-shaped pipe by welding or bonding through the plug welding hole.

[0013] Furthermore, in the secondary water supply ring of the steam generator with foreign matter interception function, the nozzle is preferably screwed to the end of the straight pipe, and the connection between the nozzle and the straight pipe is fixed by welding or bonding.

[0014] Furthermore, in the secondary side water supply ring of the steam generator with foreign matter interception function, the diameter of the filter holes is preferably 6cm-8cm.

[0015] Furthermore, in the secondary water supply ring of the steam generator with the foreign matter interception function, it is preferred that a plurality of filter holes are provided, and the total area of ​​the plurality of filter holes is larger than the cross section of the J-shaped tube.

[0016] Furthermore, in the secondary side water supply ring of the steam generator with the foreign matter interception function, the total area of ​​the plurality of filter holes is preferably greater than or equal to 1.5 times the cross-section of the J-shaped tube.

[0017] Furthermore, in the secondary side water supply ring of the steam generator with the foreign matter interception function, it is preferred that the water supply ring also includes a fixing mechanism for fixing the sleeve, which is used to fix the sleeve.

[0018] Furthermore, in the secondary water supply ring of the steam generator with foreign body interception function, the fixing mechanism preferably includes a clamp, a connector, an arc-shaped buckle shell, and an adjustment component;

[0019] The clamp is sleeved on the ring tube, the connecting piece is installed on one side of the clamp, the arc-shaped buckle shell is installed on one side of the connecting piece, and the arc-shaped buckle shell cover is buckled on one side of the J-shaped tube. The arc-shaped buckle shell is connected to the sleeve through the adjustment component to adjust the tolerance between the sleeve and different J-shaped tubes.

[0020] Further, in the secondary water supply ring of the steam generator with foreign matter interception function, the adjustment component preferably includes an arc-shaped adjustment member and a fixing member;

[0021] The two ends of the arc-shaped adjusting member are respectively adjustably mounted on the arc-shaped buckle shell and the sleeve through the fixing member.

[0022] Furthermore, in the secondary water supply ring of the steam generator with foreign matter interception function, a groove is preferably provided at the connection between the top of the nozzle and the straight pipe, and the connection between the nozzle and the straight pipe is increased in the groove by welding or bonding.

[0023] The implementation of the present invention has the following beneficial effects: it can realize the addition of foreign matter interception function to the feedwater ring of the steam generator of an in-service nuclear power plant, can effectively intercept the damage of large-sized dangerous foreign matter to the heat transfer tube, and improve nuclear safety. The design of the direction and arrangement of the filter holes will not cause unacceptable effects such as thermal shock and excessive resistance on the in-service steam generator, and has a good foreign matter interception effect.

[0024] The invention is detachable, and can be installed in the narrow space on the secondary side of the steam generator, as well as inspected and removed when foreign matter is intercepted during overhaul. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0026] Figure 1 It is a first-view structural schematic diagram of a secondary-side water supply ring of a steam generator with a foreign matter interception function according to the present invention;

[0027] Figure 2 It is a structural schematic diagram of a casing and a nozzle of a first embodiment of a secondary water supply ring of a steam generator with a foreign body interception function according to the present invention;

[0028] Figure 3 The first embodiment of the secondary water supply ring of the steam generator with foreign body interception function of the present invention Figure 2 A schematic cross-sectional structure diagram of ;

[0029] Figure 4 It is a structural schematic diagram of the fixing mechanism of the first embodiment of the secondary side water supply ring of the steam generator with foreign matter interception function of the present invention.

[0030] Explanation of the symbols in the schematic diagram:

[0031] 1. Ring pipe; 2. J-shaped pipe; 3. Casing; 4. Nozzle; 5. Filter hole; 6. Arc section pipe; 7. Straight section pipe; 8. Plug welding hole; 9. Hoop; 10. Connecting piece; 11. Arc buckle shell; 12. Arc adjusting piece; 13. Fixing piece. DETAILED DESCRIPTION

[0032] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, the specific embodiments of the present invention are now described in detail with reference to the accompanying drawings. In the following description, it should be understood that the directions or positional relationships indicated by "front", "back", "up", "down", "left", "right", "longitudinal", "horizontal", "vertical", "horizontal", "top", "bottom", "inside", "outside", "head", "tail", etc. are based on the directions or positional relationships shown in the accompanying drawings, are constructed and operated in a specific direction, and are only for the convenience of describing the present technical solution, rather than indicating that the device or element referred to must have a specific direction, and therefore cannot be understood as a limitation to the present invention.

[0033] It should also be noted that, unless otherwise clearly specified and limited, the terms such as "installed", "connected", "connected", "fixed", "set" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. When an element is referred to as being "on" or "under" another element, the element can be "directly" or "indirectly" located on the other element, or there may be one or more intermediate elements. The terms "first", "second", "third", etc. are only for the convenience of describing the present technical solution, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second", "third", etc. can explicitly or implicitly include one or more of the features. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0034] In the following description, specific details such as specific system structures and technologies are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present invention. However, it should be clear to those skilled in the art that the present invention may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, and circuits are omitted to prevent unnecessary details from obstructing the description of the present invention.

[0035] Embodiment 1: The technical solution adopted by the present invention to solve the technical problem is: Figures 1 to 4 The present invention discloses a steam generator secondary side water supply ring with a foreign body interception function, the water supply ring comprising a ring tube 1 and a J-shaped tube 2 installed on the ring tube 1, including:

[0036] The casing 3 is installed on the J-shaped tube 2;

[0037] The nozzle 4 is installed at the bottom of the sleeve 3. A filter hole 5 for intercepting foreign matter is provided on one side of the nozzle 4, and the filter hole 5 is provided on the side of the nozzle 4 facing the central area of ​​the steam generator to avoid thermal shock to the secondary side cylinder of the steam generator.

[0038] Preferably, the filter holes 5 are designed in an opening direction so that the water flows out in a direction toward the central area of ​​the steam generator, thereby avoiding thermal shock to the secondary side cylinder of the steam generator.

[0039] It is also possible that the bottom of the nozzle 4 has no hole, which can effectively intercept long strips of foreign matter.

[0040] Specifically, in order to reduce the risk of large-sized foreign objects damaging the heat transfer tubes of the steam generator from the source, the overall plan proposes to innovate the structural design of the J-tube 2 of the steam generator feed water ring, and add a foreign object interception function to effectively intercept large-sized metal foreign objects. The foreign object interception function is realized through the casing 3 and the nozzle 4 structure with multiple filter holes 5. The porous structure of the nozzle 4 is used to prevent foreign objects in the feed water from entering the secondary side of the steam generator, ensuring the stability of the unit operation and taking into account the effect of intercepting foreign objects.

[0041] In addition, the nozzle 4 adopts a structure with a filter hole 5 opened on one side, that is, the opening direction is toward the central area of ​​the steam generator, which can avoid the thermal shock on the secondary side cylinder of the steam generator when the auxiliary feed water temperature is low due to accident conditions.

[0042] Depend on Figures 2 to 3 It is shown that the sleeve 3 includes a circular arc section pipe 6 and a straight section pipe 7, one end of which is fitted on the J-shaped pipe 2;

[0043] The straight section pipe 7 is fixedly or detachably installed on the other end of the circular arc section pipe 6, or the circular arc section pipe 6 and the straight section pipe 7 are an integrated structure; at least one plug welding hole 8 is opened on the side of the circular arc section pipe 6 away from the central area of ​​the steam generator, and the circular arc section pipe 6 is welded or bonded and fixedly connected to the J-shaped pipe 2 through the plug welding hole 8.

[0044] Preferably, the inner diameter of the sleeve 3 is slightly larger than the outer diameter of the J-shaped tube 2, the arc segment tube 6 is sleeved on the bottom of the J-shaped tube 2, the straight section tube 7 is vertical and has no curvature, the arc segment tube 6 has a certain curvature, which is convenient for being sleeved on the J-shaped tube 2, and the curvature of the arc segment tube 6 is the same as that of the J-shaped tube 2.

[0045] It is also possible to preferably open a hole (plug welding hole 8) at the upper bending part of the casing 3, and plug welding is fixed to the inverted J-shaped pipe 2 of the water supply ring pipe through the opening (plug welding hole 8). Considering that the inverted J-shaped pipe 2 is arranged densely and the surrounding working space is limited, the opening plug welding design on the upper part of the casing 3 can adjust the direction of the plug welding hole 8 according to the on-site working space, which is convenient for on-site installation. It can ensure that when the plug welding fixing position of the casing 3 is loose, the nozzle 4 is self-locking with the water supply ring and does not fall off.

[0046] The nozzle 4 is screwed to the end of the straight pipe 7, and the connection between the nozzle 4 and the straight pipe 7 is fixed by welding or bonding.

[0047] Preferably, the outer surface of the straight pipe 7 is processed with an external thread, the inner wall of the nozzle 4 is processed with a corresponding internal thread, and the nozzle 4 is threadedly mounted on the straight pipe 7.

[0048] A groove 14 is provided at the connection between the top of the nozzle 4 and the straight section pipe 7, and the connection between the nozzle 4 and the straight section pipe 7 is increased in the groove 14 by welding or bonding.

[0049] It may also be preferred that after the nozzle 4 and the straight section pipe 7 are connected by tooling threads, spot welding is added to fix them. When foreign matter inside the nozzle 4 needs to be removed, the spot welding position is polished and the nozzle 4 can be screwed out. After the foreign matter is cleaned, the nozzle 4 can be reinstalled.

[0050] A portion of the groove 14 is formed on the straight section pipe 7 , and a portion of the groove 14 is formed on the top wall of the nozzle 4 .

[0051] Specifically, the nozzle 4 is designed to be a detachable structure, and foreign matter trapped inside it can be inspected and removed during overhaul.

[0052] The diameter of the filter hole 5 is 6cm-8cm.

[0053] Preferably, combined with the empirical data analysis of foreign body damage on the secondary side of the steam generator, it is determined that the diameter of the filter hole 5 of the nozzle 4 is about 7 mm, which can effectively intercept metal foreign bodies that are more harmful to the heat transfer tubes of the steam generator, and effectively reduce the risk of foreign bodies getting stuck in the tube bundle area (tube bundle spacing 8 mm) and causing continuous wear on the heat transfer tubes.

[0054] Specifically, the water supplied by the water supply ring will reach the tube bundle area below, and the tube bundle is used for heat exchange. The purpose of the filter hole 5 is to prevent large foreign matter from passing through the water supply ring to the tube bundle area and causing damage to the tube bundle.

[0055] There are a plurality of filter holes 5 , and the total area of ​​the plurality of filter holes 5 is larger than the cross section of the J-shaped tube 2 .

[0056] The total area of ​​the plurality of filtering holes 5 is greater than or equal to 1.5 times the cross section of the J-shaped tube 2 .

[0057] Preferably, the number and arrangement of the filter holes 5 on the nozzle 4 are designed to produce a low resistance, not exceeding 1 bar under operating conditions, and to ensure that the average water feed rate is less than the average water feed rate of the original J-tube 2 structure, without significantly affecting the normal water supply to the steam generator.

[0058] Embodiment 2, by Figure 1 and Figure 4The water supply ring also includes a fixing mechanism for fixing the sleeve 3 , which is used to fix the sleeve 3 .

[0059] The fixing mechanism includes a clamp 9, a connecting piece 10, an arc-shaped buckle shell 11, and an adjustment component;

[0060] The clamp 9 is sleeved on the ring tube 1, the connecting piece 10 is installed on one side of the clamp 9, the arc-shaped buckle shell 11 is installed on one side of the connecting piece 10, and the arc-shaped buckle shell 11 is buckled on one side of the J-shaped tube 2. The arc-shaped buckle shell 11 is connected to the sleeve 3 through an adjusting component to adjust the tolerance between the sleeve 3 and different J-shaped tubes 2.

[0061] Preferably, the clamp 9 is installed on the ring pipe 1 of the water supply ring, one end of the connecting piece 10 is fixed to the clamp 9 by bolts, the arc-shaped buckle shell 11 is fixed to the other end of the connecting piece 10, and the arc-shaped buckle shell 11 is buckled on the outer surface of the J-shaped tube 2.

[0062] The adjustment assembly comprises an arc-shaped adjustment member 12 and a fixing member 13 ; two ends of the arc-shaped adjustment member 12 are adjustably mounted on the arc-shaped buckle shell 11 and the sleeve 3 respectively through the fixing member 13 .

[0063] Preferably, straight slots are provided at both ends of the arc-shaped adjusting member 12, and the top of the arc-shaped buckle shell 11 and the top of the sleeve 3 are fixed to the two ends of the arc-shaped adjusting member 13 by fixing members 13, and the fixing members 13 are installed in the straight slots, and the fixing members 13 can adjust their positions in the straight slots to shorten the distance between the arc-shaped buckle shell 11 and the sleeve 3, that is, the height of the sleeve 3 installed on the J-shaped tube 2 can be adjusted. Different J-shaped tubes have different manufacturing tolerances, and adjustments are made during the installation process.

[0064] Beneficial effects obtained by the casing 3, the nozzle 4, the filter holes 5, etc.: The present invention can realize the function of adding foreign matter interception to the feedwater ring of the steam generator of the in-service nuclear power plant, and can effectively intercept the damage of large-sized dangerous foreign matter to the heat transfer tube, thereby improving nuclear safety. The design of the direction and arrangement of the filter holes 5 will not cause unacceptable effects such as thermal shock and excessive resistance on the in-service steam generator, and has a good foreign matter interception effect.

[0065] The invention is detachable, and can be installed in the narrow space on the secondary side of the steam generator, as well as inspected and removed when foreign matter is intercepted during overhaul.

[0066] It can be understood that the above embodiments only express the preferred implementation modes of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the patent scope of the present invention. It should be pointed out that, for ordinary technicians in this field, without departing from the concept of the present invention, the above technical features can be freely combined, and several deformations and improvements can be made, which all belong to the protection scope of the present invention. Therefore, all equivalent changes and modifications made to the scope of the claims of the present invention should belong to the scope covered by the claims of the present invention.

Claims

1. A steam generator secondary side water supply ring with a foreign body interception function, the water supply ring comprising a ring tube (1) and a J-shaped tube (2) installed on the ring tube (1), characterized in that: include: A sleeve (3), the sleeve (3) being mounted on the J-shaped tube (2); A nozzle (4), the nozzle (4) being installed at the bottom of the sleeve (3), a filter hole (5) for intercepting foreign matter being provided on one side of the nozzle (4), and the filter hole (5) being provided on the side of the nozzle (4) facing the central area of ​​the steam generator to avoid thermal shock to the secondary side cylinder of the steam generator.

2. The secondary side water supply ring of a steam generator with a foreign body interception function according to claim 1, characterized in that: The sleeve (3) comprises a circular arc section tube (6) and a straight section tube (7) with one end fitted on the J-shaped tube (2); The straight section pipe (7) is fixedly or detachably mounted on the other end of the circular arc section pipe (6), or the circular arc section pipe (6) and the straight section pipe (7) are an integrated structure; At least one plug welding hole (8) is provided on the side of the circular arc segment pipe (6) away from the central area of ​​the steam generator, and the circular arc segment pipe (6) is fixedly connected to the J-shaped pipe (2) by welding or bonding through the plug welding hole (8).

3. The secondary side water supply ring of a steam generator with a foreign body interception function according to claim 2, characterized in that: The nozzle (4) is screwed onto the end of the straight pipe (7).

4. The secondary water supply ring of a steam generator with a foreign body interception function according to claim 1, characterized in that: The diameter of the filter hole (5) is 6cm-8cm.

5. The secondary side water supply ring of a steam generator with a foreign matter interception function according to claim 1, characterized in that: A plurality of filtering holes (5) are provided, and the total area of ​​the plurality of filtering holes (5) is larger than the cross section of the J-shaped tube (2).

6. The secondary water supply ring of a steam generator with a foreign body interception function according to claim 5, characterized in that: The total area of ​​the plurality of filtering holes (5) is greater than or equal to 1.5 times the cross section of the J-shaped tube (2).

7. The secondary side water supply ring of a steam generator with a foreign matter interception function according to claim 1, characterized in that: Or the water supply ring further comprises a fixing mechanism for fixing the sleeve (3).

8. The secondary side water supply ring of a steam generator with a foreign matter interception function according to claim 7, characterized in that: The fixing mechanism comprises a clamp (9), a connecting piece (10), an arc-shaped buckle shell (11), and an adjustment component; The clamp (9) is sleeved on the annular tube (1), the connecting piece (10) is installed on one side of the clamp (9), the arc-shaped buckle shell (11) is installed on one side of the connecting piece (10), and the arc-shaped buckle shell (11) is buckled on one side of the J-shaped tube (2), and the arc-shaped buckle shell (11) is connected to the sleeve (3) through the adjustment component to adjust the tolerance between the sleeve (3) and different J-shaped tubes (2).

9. The secondary side water supply ring of a steam generator with a foreign matter interception function according to claim 8, characterized in that: The adjustment component comprises an arc-shaped adjustment member (12) and a fixing member (13); The two ends of the arc-shaped adjusting member (12) are respectively adjustably mounted on the arc-shaped buckle shell (11) and the sleeve (3) through the fixing member (13).

10. The secondary side water supply ring of a steam generator with a foreign matter interception function according to claim 2, characterized in that: A groove (14) is provided at the connection between the top of the nozzle (4) and the straight pipe (7), and the connection between the nozzle (4) and the straight pipe (7) is increased in the groove (14) by welding or bonding.

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