A cooling water pump for nuclear power plant equipment

Abstract

The present invention relates to the technical field of cooling water pumps, and discloses a cooling water pump for nuclear power plant equipment, which includes a motor. The output end of the motor is connected to a pump shaft through a coupling. The other end of the pump shaft is connected to a pump body. A sealing mechanism is commonly connected between the pump body and the pump shaft. The sealing mechanism includes a sealing housing, which is composed of a housing and an end cover. A stationary ring is fixedly connected inside the end cover. A moving ring is arranged on one side of the stationary ring. A telescopic member is arranged on one side of the moving ring. A plurality of elastic members are arranged on the telescopic member. The elastic members drive the telescopic member to extend so that the moving ring abuts against the stationary ring. A positioning member is arranged on one side of the fixed ring facing the arc-shaped elastic piece. The positioning member is used to limit the restoring deformation of the arc-shaped elastic piece. By arranging the plurality of elastic members in a staggered manner, the number and range of the force application points on the moving ring can be increased, ensuring that a uniform thrust is applied to the moving ring. At the same time, when the pump shaft rotates, the limiting block limits the restoring deformation of the arc-shaped elastic piece, preventing the moving ring from moving when it is impacted.

Description

Technical Field

[0001] The present invention relates to the technical field of cooling water pumps, and particularly to a cooling water pump for nuclear power plant equipment. Background Art

[0002] A nuclear power plant generates thermal energy through a nuclear reactor, and the thermal energy is then converted into electrical energy. To ensure the stable operation of various equipment in the nuclear power plant (such as motors, transformers, control equipment, etc.), it is necessary to pump cooling water through a cooling water pump to cool down the equipment.

[0003] Since the internal environment of a nuclear power plant is in a high-temperature and high-pressure state, a mechanical seal needs to be used to connect the pump shaft and the pump body of the cooling water pump. The advantages of a mechanical seal are good sealing performance, low leakage rate, and the ability to be applicable to high-pressure, high-speed, and high-temperature working conditions, meeting the application requirements of nuclear power plants. The mechanical seal mainly applies axial pressure to the moving ring through an elastic element, so that the moving ring and the static ring always maintain close contact. The existing elastic elements mainly use springs as the elastic support. During the operation of the cooling water pump, due to problems such as vibration, crosstalk, and water pressure changes, the moving ring is easily impacted. The characteristics of the spiral spring are likely to cause local stress concentration, making it difficult to apply uniform pressure to the moving ring. The side of the moving ring with less force moves away from the static ring, resulting in uneven end face gaps between the moving ring and the static ring, which easily increases the wear rate of the moving ring and the leakage probability of cooling water, posing a greater potential safety hazard to the safe operation of nuclear power plant equipment. Summary of the Invention

[0004] In view of the problem that the elastic element in the mechanical seal in the prior art is difficult to apply uniform pressure to the moving ring, resulting in gaps between the moving ring and the static ring, a cooling water pump for nuclear power plant equipment is proposed.

[0005] Its purpose is to increase the support points with the moving ring by arranging multiple elastic elements in a staggered manner, and at the same time limit the elastic elements through a limiting member during the operation of the cooling water pump to prevent the moving ring from moving after being impacted.

[0006] The technical solution of the present invention is a cooling water pump for nuclear power plant equipment, including a motor. The output end of the motor is connected to a pump shaft through a coupling. The other end of the pump shaft is connected to a pump body. A sealing mechanism is jointly connected between the pump body and the pump shaft. The sealing mechanism includes a sealing housing, which is composed of a housing and an end cover. A static ring is fixedly connected inside the end cover. A moving ring is provided on the side of the static ring facing the housing. The pump shaft movably penetrates the housing, the static ring, and the end cover. The moving ring is sleeved on the pump shaft. A telescopic member is provided on the side of the moving ring away from the static ring. The telescopic member is sleeved on the pump shaft, and a plurality of elastic members are arranged on the telescopic member. The elastic members drive the telescopic member to extend so that the moving ring abuts against the static ring.

[0007] The elastic member includes a fixing ring sleeved on the telescopic member, and a plurality of arc-shaped elastic pieces are evenly distributed on one side of the fixing ring;

[0008] A positioning member is provided on one side of the fixing ring facing the arc-shaped elastic piece. The positioning member includes a connecting ring rotatably connected to the fixing ring, and a plurality of positioning blocks are evenly distributed on the outer ring of the connecting ring. The positioning blocks are used to limit the restoration deformation of the arc-shaped elastic piece.

[0009] With the above technical solution, a plurality of elastic members are axially arranged at equal intervals and sleeved on the telescopic member. The adjacent two elastic members are in sliding contact with each other. The arc-shaped elastic pieces are in a compressed state. At this time, the plurality of elastic members cooperate to uniformly apply a thrust force towards the moving ring side to the telescopic member, so that the telescopic member extends and abuts against the moving ring, and the moving ring contacts the static ring. When the motor drives the pump shaft to rotate, the moving ring, the telescopic member, and the elastic member rotate synchronously with the pump shaft. The connecting ring drives the positioning block to contact the arc-shaped elastic piece under the action of inertia, preventing the arc-shaped elastic piece from moving towards the compressed state direction, so as to avoid the moving ring moving away from the static ring when being impacted, and keep the effective contact between the moving ring and the static ring all the time.

[0010] Further, the housing is fixedly connected to the end cover, the housing is rotatably and sealingly connected to the pump shaft, and the end cover is fixedly connected to the pump body.

[0011] With the above technical solution, the housing and the end cover are fixedly connected by bolts, and a sealing ring is provided between the housing and the end cover. Circular holes larger than the pump shaft are opened at the left end of the housing and the right end of the end cover. An O-ring is embedded in the circular hole at the left end of the housing, and the O-ring is sleeved on the pump shaft.

[0012] Further, the telescopic member includes a fixing seat sleeved on the pump shaft and a pushing ring. One side of the fixing seat facing the pushing ring is fixedly connected with a sleeve. A plurality of notches are opened on the sleeve at equal intervals in a circular shape. A plurality of arc-shaped plates are fixedly connected to one side of the pushing ring. The arc-shaped plates are slidably connected with the notches;

[0013] The fixing seat is fixedly connected to the pump shaft, and the pushing ring is arranged between the fixing seat and the moving ring.

[0014] With the above technical solution, a plurality of screw holes are opened on the fixing seat, and bolts are installed in the screw holes to abut against the outer wall of the pump shaft, so that the fixing seat is fixedly connected to the pump shaft. By using the telescopic sliding cooperation between the arc-shaped plates and the sleeve, the elastic member can drive the pushing ring to abut against the moving ring.

[0015] Further, the arc-shaped elastic piece is in a semi-circular structure in its original length state and in a sub-arc-shaped structure in its deformed state.

[0016] With the above technical solution, the arc-shaped elastic piece is made of a metal material with bending deformation and automatic restoration. By arranging a plurality of arc-shaped elastic pieces, the number of force application points on the moving ring and the area of a single force application point can be increased, so as to apply a uniform thrust to the moving ring over time.

[0017] Further, one end of the arc-shaped elastic piece is rotatably connected to the fixed ring, a connecting shaft is fixedly connected to the other end of the arc-shaped elastic piece, a plurality of arc-shaped holes are formed in the fixed ring, and the connecting shaft is slidably connected to the arc-shaped holes;

[0018] A synchronous ring is arranged on one side of the fixed ring away from the arc-shaped elastic piece, and one end of the connecting shaft passes through the arc-shaped hole and is fixedly connected to the synchronous ring.

[0019] With the above technical solution, the arc-shaped elastic piece undergoes elastic deformation through the cooperation of the connecting shaft and the arc-shaped hole, and the synchronous ring is used to connect all the arc-shaped elastic pieces, so that all the arc-shaped elastic pieces can undergo synchronous deformation, ensuring that the elastic member always applies a uniform pressure to the moving ring in the axial direction.

[0020] Further, a plurality of positioning sliding plates are fixedly arranged at equal intervals on the inner ring of the fixed ring, sliding grooves are formed on the outer side walls of the sleeve and the arc-shaped plate, and the positioning sliding plates are in sliding contact with the sliding grooves.

[0021] With the above technical solution, the fixed ring is stably arranged on the telescopic member by the cooperation of the positioning sliding plate and the sliding groove, so that the axial force application of all the elastic members is limited within the same circular range, ensuring that the push ring applies a uniform pressure to the moving ring.

[0022] Further, the cross section of the connecting ring is in a T-shaped structure, a plurality of arc-shaped grooves are formed on the inner ring of the connecting ring, the arc-shaped grooves are slidably connected to the positioning sliding plates, and a plurality of positioning blocks are fixedly connected to the outer ring of the connecting ring.

[0023] With the above technical solution, after the arc-shaped groove is connected to the positioning sliding plate, the connecting ring has a certain rotation range. When the fixed ring rotates following the pump shaft, the connecting ring rotates relative to the fixed ring under the influence of inertia, and the positioning block abuts against the connecting shaft under the influence of inertia, so that the resistance of the arc-shaped elastic piece increases during the restoration deformation. Therefore, when the moving ring is impacted and moves away from the static ring, the resistance of the arc-shaped elastic piece to restore is large, which can avoid obvious displacement of the moving ring, ensure effective contact between the moving ring and the static ring, and prevent medium leakage.

[0024] Further, a plurality of dynamic pressure grooves are arranged at equal intervals in a ring shape on one side of the connecting ring away from the fixed ring. The width of the dynamic pressure groove near the outer ring of the connecting ring is greater than the width near the inner ring of the connecting ring, and the depth of the inlet end of the dynamic pressure groove is greater than the depth of the outlet end.

[0025] With the above technical solution, after the positioning block abuts against the coupling shaft, the connecting ring rotates synchronously with the fixed ring. At this time, the inlet end of the dynamic pressure groove cuts air or liquid, thereby increasing the inertial influence of the connecting ring and increasing the resistance exerted by the positioning block on the coupling shaft. At the same time, when the air or liquid passes through the inclined surface of the dynamic pressure groove, the rotational friction between the connecting ring and the fixed ring increases, enhancing the limiting stability of the positioning block on the coupling shaft.

[0026] Further, a cooling cavity is formed on the housing, a connecting pipe opening communicated with the cooling cavity is fixedly arranged on the housing, a water guide pipe is fixedly connected to the connecting pipe opening, and the other ends of the two water guide pipes are respectively communicated with the water inlet and the water outlet of the pump body.

[0027] With the above technical solution, when the water pump conveys cooling water, the water inlet of the pump body conveys part of the cooling water into the cooling cavity through the water guide pipe. After this part of the cooling water absorbs the heat in the sealing shell, it then flows to the water outlet of the pump body through the other water guide pipe, so that the inside of the sealing shell can be cooled, avoiding the reduction of the elastic force effect of the arc-shaped elastic piece in a long-term high-temperature environment.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] 1. By arranging multiple elastic members in a staggered manner, the number and range of force application points on the moving ring can be increased, ensuring uniform thrust on the moving ring, keeping uniform contact between the moving ring and the static ring. At the same time, when the elastic members rotate following the pump shaft, the connecting ring drives the limiting block to move under the influence of inertia, limiting the restoring deformation of the arc-shaped elastic piece, making it difficult for the elastic members to be compressed and deformed during rotation, avoiding the movement of the moving ring when it is impacted, and preventing the generation of gaps between the moving ring and the static ring, thus avoiding medium leakage.

[0030] 2. When the connecting ring rotates following the fixed ring, the dynamic pressure groove cuts air or liquid, which can increase the limiting effect of the limiting block on the arc-shaped elastic piece. At the same time, when the air or liquid passes through the inclined surface of the dynamic pressure groove, the contact between the connecting ring and the fixed ring becomes closer, ensuring the limiting stability of the limiting block on the arc-shaped elastic piece.

[0031] 3. By connecting the water guide pipe with the pump body and the cooling cavity, when the pump body conveys cooling water, part of the cooling water passes through the cooling cavity, enabling the inside of the sealing shell to be cooled, avoiding the reduction of the elastic force effect of the arc-shaped elastic piece in a long-term high-temperature environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a schematic three-dimensional structure diagram of the whole of the present invention;

[0033] Figure 2 is a schematic cross-sectional structure diagram of the sealing shell of the present invention;

[0034] Figure 3It is a schematic diagram of the disassembly of the telescopic member structure of the present invention;

[0035] Figure 4 It is a schematic cross-sectional view of the structure of the static ring, the dynamic ring and the telescopic member of the present invention;

[0036] Figure 5 It is a schematic diagram of the elastic member structure of the present invention;

[0037] Figure 6 It is a schematic diagram of the disassembly of the fixing ring, arc-shaped spring piece and synchronization ring structure of the present invention;

[0038] Figure 7 It is a schematic diagram of the structure of the connecting shaft and the positioning block of the present invention;

[0039] Figure 8 It is a schematic diagram of the disassembly of the fixing ring and the connecting ring structure of the present invention;

[0040] Figure 9 For the present invention Figure 7 A schematic diagram of the enlarged structure in the middle.

[0041] In the figure:

[0042] 1. Motor; 2. Pump shaft; 3. Pump body; 4. Sealing shell; 41. Shell; 42. End cover; 43. Cooling chamber; 44. Pipe connection; 5. Static ring; 6. Dynamic ring; 7. Telescopic member; 71. Fixed seat; 72. Push ring; 73. Sleeve; 74. Arc plate; 75. Slide groove; 8. Elastic member; 81. Fixed ring; 82. Positioning slide plate; 83. Arc spring piece; 84. Connecting shaft; 85. Arc hole; 86. Synchronous ring; 9. Positioning member; 91. Connecting ring; 92. Arc groove; 93. Positioning block; 94. Dynamic pressure groove; 10. Water guide pipe. DETAILED DESCRIPTION

[0043] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0044] Example 1, reference Figures 1 - 6, which is the first embodiment of the present invention, provides a cooling water pump for nuclear power plant equipment, including a motor 1. The output end of the motor 1 is connected to a pump shaft 2 through a coupling. The other end of the pump shaft 2 is connected to a pump body 3. A sealing mechanism is jointly connected between the pump body 3 and the pump shaft 2. The sealing mechanism includes a sealing housing 4, and the sealing housing 4 is composed of a housing body 41 and an end cover 42. A stationary ring 5 is fixedly connected inside the end cover 42. A moving ring 6 is provided on one side of the stationary ring 5 facing the housing body 41. The pump shaft 2 movably penetrates through the housing body 41, the stationary ring 5, and the end cover 42. The moving ring 6 is sleeved on the pump shaft 2. A telescopic member 7 is provided on one side of the moving ring 6 away from the stationary ring 5. The telescopic member 7 is sleeved on the pump shaft 2, and a plurality of elastic members 8 are arranged on the telescopic member 7. The elastic members 8 drive the telescopic member 7 to extend so that the moving ring 6 abuts against the stationary ring 5; the elastic member 8 includes a fixing ring 81 sleeved on the telescopic member 7, and a plurality of arc-shaped elastic pieces 83 are evenly distributed on one side of the fixing ring 81; a positioning member 9 is provided on one side of the fixing ring 81 facing the arc-shaped elastic piece 83. The positioning member 9 includes a connecting ring 91 rotatably connected to the fixing ring 81, and a plurality of positioning blocks 93 are evenly distributed on the outer ring of the connecting ring 91. The positioning blocks 93 are used to limit the restoration deformation of the arc-shaped elastic piece 83.

[0045] Specifically, a plurality of elastic members 8 are axially equidistantly arranged and sleeved on the telescopic member 7. The adjacent two elastic members 8 are in sliding contact with each other. The arc-shaped elastic piece 83 is in a compressed state. At this time, the plurality of elastic members 8 cooperate to uniformly apply a thrust towards the moving ring 6 to the telescopic member 7, so that the telescopic member 7 extends and abuts against the moving ring 6, making the moving ring 6 contact with the stationary ring 5. When the motor 1 drives the pump shaft 2 to rotate, the moving ring 6, the telescopic member 7, and the elastic member 8 rotate synchronously with the pump shaft 2. The connecting ring 91 drives the positioning block 93 to contact the arc-shaped elastic piece 83 under the action of inertia, preventing the arc-shaped elastic piece 83 from moving towards the compressed state direction, so as to avoid the moving ring 6 moving away from the stationary ring 5 when being impacted, and keeping the effective contact between the moving ring 6 and the stationary ring 5 all the time.

[0046] Refer to Figure 4 , an annular groove is opened on the inner side wall of the moving ring 6, and an O-ring is arranged in the annular groove. The O-ring is sleeved on the pump shaft 2, improving the sealing performance between the moving ring 6 and the pump shaft 2, preventing the leakage of the medium. At the same time, the O-ring has good elasticity and flexibility, and can adapt to the slight displacement changes of the moving ring 6 within a certain range, compensating for the vibration of the water pump and the axial displacement of the pump shaft 2 through its own deformation, maintaining good contact with the moving ring 6 and the pump shaft 2, and maintaining the sealing effect.

[0047] Refer to Figure 2 , the housing body 41 and the end cover 42 are fixedly connected, the housing body 41 is in sealed rotational connection with the pump shaft 2, and the end cover 42 is fixedly connected to the pump body 3.

[0048] Specifically, the housing 41 and the end cover 42 are fixedly connected by bolts, and a sealing ring is provided between the housing 41 and the end cover 42. Round holes larger than the pump shaft 2 are provided at the left end of the housing 41 and the right end of the end cover 42. An O-ring is embedded in the round hole at the left end of the housing 41, and the O-ring is sleeved on the pump shaft 2.

[0049] Referring to Figures 3 - 4 , the telescopic member 7 includes a fixed seat 71 sleeved on the pump shaft 2 and a push ring 72. A sleeve 73 is fixedly connected to one side of the fixed seat 71 facing the push ring 72. A plurality of notches are provided at equal intervals in a ring shape on the sleeve 73. A plurality of arc-shaped plates 74 are fixedly connected to one side of the push ring 72, and the arc-shaped plates 74 are slidably connected with the notches; the fixed seat 71 is fixedly connected to the pump shaft 2, and the push ring 72 is arranged between the fixed seat 71 and the moving ring 6.

[0050] Specifically, a plurality of screw holes are provided on the fixed seat 71, and bolts are installed in the screw holes to abut against the outer wall of the pump shaft 2, so that the fixed seat 71 is fixedly connected to the pump shaft 2. By the telescopic sliding fit of the arc-shaped plates 74 and the sleeve 73, the elastic member 8 can drive the push ring 72 to abut against the moving ring 6.

[0051] Referring to Figures 5 - 6 , the arc-shaped elastic piece 83 is in a semi-circular structure in its original length state and in a sub-arc-shaped structure in its deformed state.

[0052] Specifically, the arc-shaped elastic piece 83 is made of a metal material with bending deformation and automatic restoration. By arranging a plurality of arc-shaped elastic pieces 83, the number of force application points on the moving ring 6 and the area of a single force application point can be increased, so as to exert a uniform thrust on the moving ring 6 over time.

[0053] Referring to Figure 6 , one end of the arc-shaped elastic piece 83 is rotatably connected to the fixed ring 81, the other end of the arc-shaped elastic piece 83 is fixedly connected with a connecting shaft 84, a plurality of arc-shaped holes 85 are provided on the fixed ring 81, and the connecting shaft 84 is slidably connected with the arc-shaped holes 85; a synchronous ring 86 is provided on the side of the fixed ring 81 away from the arc-shaped elastic piece 83, and one end of the connecting shaft 84 passes through the arc-shaped hole 85 and is fixedly connected with the synchronous ring 86.

[0054] Specifically, the arc-shaped elastic piece 83 undergoes elastic deformation through the cooperation of the connecting shaft 84 and the arc-shaped holes 85. By connecting all the arc-shaped elastic pieces 83 with the synchronous ring 86, all the arc-shaped elastic pieces 83 can undergo synchronous deformation, ensuring that the elastic member 8 always exerts a uniform pressure on the moving ring 6 in the axial direction.

[0055] Referring to Figure 3 And Figure 5 , a plurality of positioning sliding plates 82 are fixedly arranged at equal intervals on the inner ring of the fixed ring 81. Sliding grooves 75 are provided on the outer side walls of the sleeve 73 and the arc-shaped plates 74, and the positioning sliding plates 82 are in sliding contact with the sliding grooves 75.

[0056] Specifically, the positioning slide plate 82 is used in cooperation with the chute 75 to stably set the fixing ring 81 on the telescopic member 7, so that the axial force application of all the elastic members 8 is limited within the same circular range, ensuring that the pushing ring 72 uniformly applies pressure to the moving ring 6.

[0057] Among them, referring to Figure 2 , the arc-shaped elastic pieces 83 in two adjacent elastic members 8 are arranged staggeredly, so that the number of force application points to the moving ring 6 can be increased, and the uniformity of force application can be further improved.

[0058] Among them, the sleeve 73 and the arc-shaped plate 74 can be disassembled. By selecting the number of elastic members 8 to increase or decrease, it can meet different application scenarios, improve the application range, and when a single elastic member 8 is damaged, it can be replaced separately, reducing the maintenance cost.

[0059] Embodiment 2, referring to Figures 6 - 9 , is the second embodiment of the present invention. The difference between this embodiment and the first embodiment is that the cross-section of the connecting ring 91 is in a T-shaped structure. A plurality of arc-shaped grooves 92 are formed on the inner ring of the connecting ring 91. The arc-shaped grooves 92 are slidably connected with the positioning slide plate 82, and a plurality of positioning blocks 93 are fixedly connected to the outer ring of the connecting ring 91.

[0060] Specifically, after the arc-shaped groove 92 is connected with the positioning slide plate 82, the connecting ring 91 has a certain rotation range. When the fixing ring 81 rotates following the pump shaft 2, the connecting ring 91 rotates relative to the fixing ring 81 due to inertia. The positioning block 93 abuts against the connecting shaft 84 due to inertia, so that the resistance of the arc-shaped elastic piece 83 during the restoration deformation increases. Therefore, when the moving ring 6 is impacted and moves away from the static ring 5, the resistance of the arc-shaped elastic piece 83 to restore is relatively large, which can prevent the moving ring 6 from having obvious displacement, ensure the effective contact between the moving ring 6 and the static ring 5, and avoid medium leakage.

[0061] Referring to Figure 9 , a plurality of dynamic pressure grooves 94 are formed on the side of the connecting ring 91 away from the fixing ring 81 at equal intervals in a ring shape. The width of the dynamic pressure groove 94 near the outer ring of the connecting ring 91 is greater than the width near the inner ring of the connecting ring 91, and the depth of the inlet end of the dynamic pressure groove 94 is greater than the depth of the outlet end.

[0062] Specifically, after the positioning block 93 abuts against the connecting shaft 84, the connecting ring 91 rotates synchronously with the fixing ring 81. At this time, the inlet end of the dynamic pressure groove 94 cuts air or liquid, thereby increasing the inertial influence of the connecting ring 91, increasing the resistance applied by the positioning block 93 to the connecting shaft 84. At the same time, when the air or liquid passes through the inclined surface of the dynamic pressure groove 94, the rotational friction force between the connecting ring 91 and the fixing ring 81 increases, improving the limiting stability of the positioning block 93 to the connecting shaft 84. The remaining structures are the same as those in Embodiment 1.

[0063] Embodiment 3, referring to Figures 1 - 2, which is the third embodiment of the present invention. This embodiment is different from the second embodiment in that a cooling chamber 43 is opened on the shell 41, and a pipe port 44 connected to the cooling chamber 43 is fixedly provided on the shell 41. A water pipe 10 is fixedly connected to the pipe port 44, and the other ends of the two water pipes 10 are respectively connected to the water inlet and the water outlet of the pump body 3.

[0064] Specifically, when the water pump is delivering cooling water, the water inlet of the pump body 3 delivers part of the cooling water to the cooling cavity 43 through the water conduit 10, and the cooling water absorbs the heat in the sealed shell 4 and then flows to the water outlet of the pump body 3 through another water conduit 10, so that the inside of the sealed shell 4 can be cooled, and the arc-shaped spring piece 83 is prevented from reducing the elastic effect in a long-term high temperature environment. The rest of the structure is the same as that of Example 2.

[0065] Based on Examples 1-3, the working principle of the present invention is as follows: the rotation of the motor 1 drives the pump shaft 2 to rotate, and the pump shaft 2 drives the impeller in the pump body 3 to rotate, so that the pump body 3 delivers cooling water to cool the nuclear power plant equipment. During the rotation of the pump shaft 2, the arc-shaped spring piece 83 in a compressed and force-accumulated state applies a thrust to the push ring 72, so that the push ring 72 abuts against the moving ring 6, so that the moving ring 6 and the static ring 5 maintain a rotational contact, thereby avoiding leakage of the medium between the pump body 3 and the sealing shell 4. At the same time, when the pump shaft 2 rotates rapidly, the connecting ring 91 is affected by inertia to drive the positioning block 93 to abut against the connecting shaft 84, preventing the arc-shaped spring piece 83 from deforming in the recovery direction, thereby avoiding the moving ring 6 from moving in the opposite direction when impacted, and ensuring that the moving ring 6 always maintains effective contact with the static ring 5.

[0066] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A cooling water pump for nuclear power plant equipment, comprising a motor, wherein the output end of the motor is connected to a pump shaft through a coupling, the other end of the pump shaft is connected to a pump body, and a sealing mechanism is commonly connected between the pump body and the pump shaft, characterized in that: The sealing mechanism comprises a sealing shell, which is composed of a shell and an end cover. A static ring is fixedly connected inside the end cover. A dynamic ring is arranged on one side of the static ring facing the shell. The pump shaft movably passes through the shell, the static ring and the end cover. The dynamic ring is sleeved on the pump shaft. A telescopic member is arranged on the side of the dynamic ring away from the static ring. The telescopic member is sleeved on the pump shaft and a plurality of elastic members are arranged on the telescopic member. The elastic member drives the telescopic member to stretch so that the dynamic ring abuts against the static ring. The elastic member comprises a fixing ring sleeved on the telescopic member, a plurality of arc-shaped spring pieces are evenly distributed on one side of the fixing ring, one end of the arc-shaped spring piece is rotatably connected to the fixing ring, the other end of the arc-shaped spring piece is fixedly connected to a connecting shaft, a plurality of arc-shaped holes are opened on the fixing ring, the connecting shaft is slidably connected to the arc-shaped holes, a synchronizing ring is provided on one side of the fixing ring away from the arc-shaped spring piece, one end of the connecting shaft passes through the arc-shaped hole and is fixedly connected to the synchronizing ring; A positioning member is provided on the side of the fixing ring facing the arc-shaped spring piece. The positioning member includes a connecting ring rotatably connected to the fixing ring. A plurality of positioning blocks are evenly distributed on the outer ring of the connecting ring. The positioning blocks are used to limit the restoring deformation of the arc-shaped spring piece.

2. The cooling water pump for nuclear power plant equipment according to claim 1, characterized in that: The shell and the end cover are connected and fixed, the shell and the pump shaft are sealingly rotatably connected, and the end cover is connected and fixed to the pump body.

3. The cooling water pump for nuclear power plant equipment according to claim 1, characterized in that: The telescopic member comprises a fixed seat and a push ring sleeved on the pump shaft, the fixed seat is fixedly connected with a sleeve on one side facing the push ring, a plurality of notches are formed in an annular shape and at equal intervals on the sleeve, a plurality of arc plates are fixedly connected with one side of the push ring, and the arc plates are slidably connected with the notches; The fixing seat is connected and fixed to the pump shaft, and the push ring is arranged between the fixing seat and the moving ring.

4. The cooling water pump for nuclear power plant equipment according to claim 1, characterized in that: The arc-shaped spring piece is in a semicircular structure in the original length state, and in a deformed state, the arc-shaped spring piece is in a inferior arc-shaped structure.

5. The cooling water pump for nuclear power plant equipment according to claim 3, characterized in that: A plurality of positioning slide plates are fixedly arranged at equal intervals on the inner ring of the fixed ring, and sliding grooves are provided on the outer side walls of the sleeve and the arc-shaped plate, and the positioning slide plates are in sliding contact with the sliding grooves.

6. The cooling water pump for nuclear power plant equipment according to claim 5, characterized in that: The cross section of the connecting ring is T-shaped, a plurality of arc grooves are provided on the inner ring of the connecting ring, the arc grooves are slidably connected to the positioning slide plate, and a plurality of positioning blocks are fixedly connected to the outer ring of the connecting ring.

7. The cooling water pump for nuclear power plant equipment according to claim 6, characterized in that: A plurality of dynamic pressure grooves are formed in an annular shape and at equal intervals on one side of the connecting ring away from the fixed ring. The width of the dynamic pressure groove close to the outer ring of the connecting ring is greater than the width close to the inner ring of the connecting ring. The depth of the inlet end of the dynamic pressure groove is greater than the depth of the outlet end.

8. The cooling water pump for nuclear power plant equipment according to claim 1, characterized in that: A cooling cavity is provided on the shell, a pipe connection port connected to the cooling cavity is fixedly provided on the shell, a water pipe is fixedly connected to the pipe connection port, and the other ends of the two water pipes are respectively connected to the water inlet and the water outlet of the pump body.

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