WO2013143451A1

WO2013143451A1 - Spray pump for containment vessel

Info

Publication number: WO2013143451A1
Application number: PCT/CN2013/073221
Authority: WO
Inventors: 陆金琪; 顾兴涛
Original assignee: 上海阿波罗机械股份有限公司
Priority date: 2012-03-27
Filing date: 2013-03-26
Publication date: 2013-10-03
Also published as: CN102606537A

Abstract

A spray pump for a containment vessel applicable in the field of nuclear power equipment comprises an inner barrel (1), an outer barrel (2), a pump seat (3), a pump shaft (4), and a bearing body (5). The inner barrel (1) comprises a flow guiding section (11), a water outlet section (12), a flow guiding shell section (13), a suction section (14), and a suction pipe (15) sequentially connected from top to bottom. The flow guiding shell section (13) is formed of multiple stages of flow guiding shells connected in series. A first flange and a second flange are arranged at the upper end and the lower end of the outer wall of the flow guiding section (11), respectively. A third flange and a fourth flange are arranged at the upper end and the lower end of the outer wall of the water outlet section (12), respectively. An inner flange on the pump seat (3) is connected to the first flange, and the second flange is connected to the third flange. First reinforcing plates (111) for connecting the first flange and the second flange are arranged on the outer wall of the flow guiding section (11). Second reinforcing plates (121) for connecting the third flange and the fourth flange are arranged on the outer wall of the water outlet section (12). The number of the first reinforcing plates (111) is the same as that of the second reinforcing plates (121), and is an even number greater than or equal to four.

Description

Safety shell spray pump

Technical field

The invention relates to a safety shell spray pump for use in the field of nuclear power equipment in the field of nuclear power equipment. Background technique

The PWR nuclear power plant is the main form of nuclear power plants. The water boils inside the core of the pressurized water reactor, so the water must be kept at a high pressure. The nuclear island includes a nuclear steam supply system, a safety sprinkler system and an auxiliary system.

The containment spray system consists of two separate lines. Each piping system consists of spray pumps, coolers, spray heads, refueling tanks, valves and other equipment. The containment spray pump is the last barrier to block fission products from fuel and primary loop radioactive materials into the environment. When a safety accident occurs, the high temperature and high pressure water in the primary circuit flows into the containment, causing the temperature and pressure in the containment to rise, and the safety spray nozzle sprays the cold water, which is the condensation of water vapor in the containment into water. Reduce the pressure and temperature inside the containment. At the same time, the spray water contains boric acid to remove radioactive iodine from the air.

In order to ensure efficient treatment of reactor failures, the containment spray pump must maintain a certain natural frequency during operation. The recommended standard for the self-vibration frequency is not less than 33 Hz, and the current self-vibration frequency of the containment spray pump is generally only 22-28 Hz, which cannot guarantee the effective treatment of the reactor accident. The self-vibration frequency of the containment spray pump is related to the inner cylinder structure of the containment spray pump.

When the nuclear power plant system is in safe operation, the function of the safety shell spray pump is: injecting water in the water change tank of the nuclear power plant system into the safety shell, maintaining the balance of pressure inside and outside the safety shell, and thus operating normally in the nuclear power plant system In this case, the containment spray pump can also be referred to as a low pressure injection pump. Summary of the invention

The object of the present invention is to overcome the deficiencies of the prior art and provide a safety shell spray pump whose self-vibration frequency can meet the recommended standard of the nuclear power plant system for the natural vibration frequency of the safety shell spray pump, and ensure the effective treatment of the reactor accident. .

A technical solution for achieving the above object is: a safety shell spray pump comprising an inner cylinder body, an outer cylinder body, a pump seat, a pump shaft and a bearing body;

An inlet flange, an outlet flange, an outer flange, an inner flange, and the pump seat are disposed on the pump seat a top mounting hole; the inlet flange communicates with the outer flange, the inner flange communicates with the outlet flange; the outer flange is fixed to the outer cylinder; the inner flange Fixed on the inner cylinder, the pump shaft penetrates the bearing body, and extends from the upper mounting hole into the pump seat, and penetrates the entire inner cylinder from top to bottom;

The inner cylinder includes a flow guiding section, a water outlet section, a flow guiding shell section, a suction section and a suction pipe connected in sequence from top to bottom, wherein the guiding shell section is formed by connecting a plurality of stages of flow guiding shells in series ;

The pump shaft is sleeved with a plurality of stages of impellers arranged in the axial direction of the pump shaft, and the positions of the impellers of each stage and the diversion shells of the stages on the diversion shell section are one-to-one correspondence of;

a first flange and a second flange are respectively disposed on upper and lower ends of the outer wall of the flow guiding section, and a third flange and a fourth flange are respectively disposed on upper and lower ends of the outer wall of the water outlet section, and the pump seat is respectively The inner flange is connected to the first flange, and the second flange is connected to the third flange;

a first rib connecting the first flange and the second flange is disposed on an outer wall of the flow guiding section, and an outer wall of the water outlet section is provided with a connection between the third flange and the fourth flange The second rib is equal in number to the first rib and the second rib, and is an even number greater than or equal to four.

Further, inside the inner cylinder, a third rib is arranged around the inner circumference of the water discharge section, and the pump seat is arranged around the circumference of the pump seat, and the inner flange is connected And the fourth rib of the outer flange, the number of the first rib, the second rib, the third rib, and the fourth rib are the same.

Further, the pump shaft is sleeved with the first water guiding bearing and the second water guiding bearing; wherein the first water guiding bearing is located between the pump shaft and the radial direction of the water outlet section, the second A water guiding bearing is located between the pump shaft and the radial direction of the suction pipe.

Further, the first water guiding bearing and the second water guiding bearing are static pressure bearings, and the first water guiding bearing and the second water guiding bearing are all made of Z2CN18-10 type stainless steel. The inner walls of the first water guiding bearing and the second water guiding bearing are coated with a coating coated with a nickel-based alloy or a wear resistant material.

Further, in the inner cylinder body, a fixing seat is arranged on the top of the water outlet section; the pump shaft is fixedly sleeved on the sand tray, and the sanding tray is located above the fixing seat, and the top surface of the fixing seat A drainage channel is formed between the bottom surface of the sand tray.

Further, the pump shaft is also sleeved with an induction wheel, and the induction wheel is located between the first stage impeller and the second water guide bearing, between the first stage impeller and the induction wheel, and the water Guide bearing and the lure The sleeve is sleeved on the pump shaft between the guide wheels.

Still further, the inducer wheel includes a hub that is sleeved on the pump shaft and a tapered outer edge that is disposed on the hub.

Further, a mechanical seal structure is disposed between the pump shaft and the upper mounting hole of the pump base, the mechanical seal structure includes: a throttle bush sleeve sleeved on an inner wall of the upper mounting hole and sleeved at a sealing sleeve on the outer wall of the pump shaft, a spiral seal is disposed on an outer wall of the sealing sleeve, and a sealing end surface of the mechanical sealing structure is formed between the spiral seal and the throttle bushing.

Further, a thrust bearing is disposed between the bearing body and the mechanical seal structure.

Further, a bottom end of the pump shaft is provided with a shaft head.

According to the technical solution of a safety shell spray pump of the present invention, the inner cylinder body includes a flow guiding section, a water outlet section, a flow guiding shell section, a suction section and a suction pipe which are sequentially connected from top to bottom, a first rib connecting the first flange and the second flange is disposed on the outer wall of the flow guiding section, and a technical solution for connecting the second rib of the third flange and the fourth flange is disposed on the outer wall of the water outlet section . The technical effect is as follows: The self-vibration frequency of the safety shell spray pump is increased from 22 to 28 Hz to above 33 Hz, which satisfies the recommended standard for the nuclear power system's self-vibration frequency of the safety shell spray pump. DRAWINGS

1 is a schematic view showing the overall structure of a safety shell spray pump of the present invention.

Fig. 2 is an enlarged schematic view showing a portion A of Fig. 1.

Fig. 3 is an enlarged schematic view showing a portion B of Fig. 1.

Fig. 4 is an enlarged schematic view showing a portion C of Fig. 1.

Figure 5 is a schematic view showing the structure of a first water guiding bearing of a safety shell spray pump of the present invention.

Figure 6 is a schematic view showing the structure of a second water guiding bearing of a safety shell spray pump of the present invention.

Figure 7 is a schematic view showing the structure of an induction wheel of a safety shell spray pump of the present invention. detailed description

Referring to FIG. 1 to FIG. 7, in order to better understand the technical solution of the present invention, detailed description will be made below through specific embodiments and with reference to the accompanying drawings:

Referring to FIG. 1 , in order to better understand the technical solution of the present invention, the following is specifically The embodiments are described in detail with reference to the accompanying drawings:

Referring to Figure 1, a safety shell spray pump of the present invention comprises: an inner cylinder 1, an outer cylinder 2, a pump base 3, a pump shaft 4 and a bearing body 5;

The pump base 3 is provided with an inlet flange 31, an outlet flange 32, an outer flange 33, an inner flange 34, and an upper mounting hole 35 at a top end of the pump base 3; the inlet flange 31 communicates with the An outer flange 33, the inner flange 32 communicates with the outlet flange 34.

In this embodiment, the angle between the inlet flange 31 and the outlet flange 32 is 90 degrees. An upper flange 21 is disposed on the top of the outer cylinder 2, and the outer flange 33 is fixed to the upper flange 21 by bolts to fix the outer cylinder 2 and the pump base 3.

The inner cylinder 1 includes a flow guiding section 11, a water outlet section 12, a flow guiding shell section 13 and a suction section 14 and a suction pipe 15 which are connected in order from top to bottom, wherein the flow guiding shell section 13 is guided by a multi-stage The flow shells are connected in series. In this embodiment, the flow guiding shell segments 13 are preferably formed by a series of three-stage diversion shells. A plurality of suction cones 151 are disposed on the suction pipe 15

The shape of the axial section of the outer wall of the water guiding section 11 and the water outlet section 12 is a "work" shape, that is, the upper and lower ends of the outer wall of the air guiding section 11 are respectively provided with a first flange and a second flange, a third flange and a fourth flange are respectively disposed at upper and lower ends of the outer wall of the water outlet section 12, and the inner flange 34 of the pump base 3 is fixed to the first flange of the flow guiding section 11 by bolts. The second flange on the flow guiding section 11 is fixed to the third flange of the water discharge section 12 by bolts. Thus, the pump base 3 and the inner cylinder 1 are fixed.

The top of the flow guiding shell section 13 is fixed to the bottom of the water discharge section 12 by screws, and the bottom of the flow guiding shell section 13 is fixed to the top of the suction section 14 by screws. A fifth flange is disposed at a top end of the outer wall of the suction section 14, and the fourth flange of the water discharge section 12 is fixed to the fifth flange on the suction section 14 by a wear bar 16.

The fourth flange on the water discharge section 12, the fifth flange of the suction section 14 and the suction pipe 15 are fixed by a return pipe 17. A return pipe bracket 18 is disposed on the connecting portion of the return pipe 17 and the fifth flange.

Thus, the flow guiding section 11, the water outlet section 12, the flow guiding shell section 13, the suction section 14 and the suction pipe 15 are integrally connected. The inner cylinder 1 is formed. The function of the wear bar 16 and the return pipe 17 is to enhance the rigidity of the inner cylinder 1. The greatest improvement of a containment spray pump of the present invention is that the structure of the inner cylinder 1 is improved, that is, on the outer wall of the flow guiding section 11, a joint is provided along the circumference of the outer wall of the flow guiding section 11. a first flange and a first rib 111 of the second flange; on an outer wall of the water discharge section 12, along the circumference of the outer wall of the water discharge section 12, a connection connecting the third flange and the The second rib 121 of the fourth flange has the same number of the first rib 111 and the second rib 121, and is an even number greater than or equal to four. In this embodiment, the number of the first rib 111 and the second rib 121 is eight.

The purpose of the first rib 111 and the second rib 121 is to effectively increase the natural frequency of the safety spray pump, and the self-vibration of the safety spray pump is improved after the improvement. The frequency has reached 33 Hz or more, which is obviously higher than the original 22~28 Hz, and meets the recommended standard of the nuclear power plant system for the self-vibration frequency of the safety shell spray pump. The greater the number of the first ribs 111 and the second ribs 121, the more advantageous it is to increase the natural frequency of the containment spray pump, but it will increase the difficulty in manufacturing the casting.

Further, inside the inner cylinder 1, a third rib 122 is arranged around the inner circumference of the water discharge section 12, and the pump base 3 is arranged around the circumference of the pump base 3, and is connected The inner flange 34 and the fourth rib 36 of the outer flange 33, the first rib 111, the second rib 121, the third rib 122, and the fourth rib 36 The number is the same.

The function of the third rib 122 and the fourth rib 36 is to further increase the natural frequency of the safety spray pump to above 35 Hz.

Then, in the embodiment, a technical measure for increasing the screw pitch of the inner flange 34 is adopted to increase the natural frequency of the safety shell spray pump. In the prior art, the inner flange 34 has a screw pitch of 580 mm, and the inner flange 34 has a screw pitch of 630 mm in this embodiment. Correspondingly, the screw pitches of the first flange, the second flange, the third flange and the fourth flange are correspondingly increased to 630 mm. At the same time, the screw pitch of the outer flange 33 remains unchanged, still 1000 m, and the screw pitch of the upper flange 21 remains unchanged.

The bearing body 5 is disposed at a top end of the safety shell spray pump, and the pump shaft 4 passes through the bearing body 5 from top to bottom, and extends into the upper mounting hole 35 of the pump base 3 The containment spray pump extends from the first flange into the inner cylinder 1 and extends through the entire inner cylinder 1. The suction pipe 15 is sleeved with the pump shaft 4.

The pump shaft 4 is sleeved with a plurality of stages of impellers 41 arranged in the axial direction of the pump shaft 4, and the number of stages of the impeller 41 is the same as the number of stages of the flow guiding shell on the flow guiding shell section 13, It is three levels. And the impeller 41 The position in the axial direction of the pump shaft 4 is also in one-to-one correspondence with the position of the flow guiding shell of each stage on the flow guiding shell section 13. In the present embodiment, the impellers 41 arranged in the three axial directions along the pump shaft 4 are the first stage impeller, the second stage impeller and the final stage impeller from bottom to top.

In this embodiment, the impeller 41 is a centrifugal single-stage impeller, and a front seal ring 411 and a rear seal ring 412 are disposed between the impeller 41 and the guide shell corresponding to the guide shell segment 13 . And balancing holes 413.

The purpose of this design is to balance the axial forces experienced by the pump shaft 4.

The outer surface of the impeller 41 and the flow guiding shells on the flow guiding shell section 13 have an arc-shaped axial section. The purpose of this design is to increase the overcurrent capability of the containment spray pump.

The pump shaft 4 is also sleeved with a first water guiding bearing 42, a second water guiding bearing 43 and an inducer wheel respectively.

44.

The first water guiding bearing 42 is located between the pump shaft 4 and the radial direction of the water discharge section 12, and the second water guiding bearing 43 is located in the radial direction of the pump shaft 4 and the suction pipe 15. between.

The first water guiding bearing 42 and the second water guiding bearing 43 function to support the pump shaft 4 to stabilize the center of rotation of the pump shaft 4.

The entirety of the first water guiding bearing 42 and the second water guiding bearing 43 are made of Z2CN18-10 type stainless steel, which is dedicated to the field of nuclear power. The inner walls of the first water guiding bearing 42 and the second water guiding bearing 43 are provided with a coating of a nickel-based alloy or a wear resistant material, and in this embodiment, a M60 build-up coating is preferred. The reason for this design is: Ni60 is a high-hardness nickel-chromium-boron-silicon alloy with wear resistance, corrosion resistance, high temperature resistance, etc. It can meet startup and shutdown transients, cold water operation, hot water operation, thermal transients, and small flow. Under the condition of operating with impregnated water, the first water guiding bearing 42 and the second water guiding bearing 43 do not wear.

As shown in FIG. 5, the first water guiding bearing 42 is provided with five evenly arranged flow guiding holes 421, and the guiding holes 421 are all connected to the H-shaped groove 422 on the inner wall of the first water guiding bearing 42. Further, the first water guiding bearing 42 is further provided with an axial guiding flow hole 423 that penetrates the flow guiding hole 421. As shown in FIG. 6, the second water guiding bearing 43 is provided with five evenly arranged flow guiding holes 431, and the guiding holes 431 are connected to the H-shaped grooves on the inner wall of the second water guiding bearing 43. 432.

The purpose of such a design is to make the first water guiding bearing 42 and the second water guiding bearing 43 a static pressure bearing by the pressure of the lubricating medium, and to ensure the stability of the pump shaft 4 at the center of rotation. Through this special The design of the first water guiding bearing 42 and the second water guiding bearing 43 is improved to ensure the operability of the safety shell spray pump.

The base of the first water guiding bearing 42 is provided with four bolt holes for fixing the first water guiding bearing 42 and the bottom of the water outlet section 12. The base of the second water guiding bearing 43 is provided with four bolt holes for fixing the second water guiding bearing 43 and the bottom wall of the suction pipe 15.

The inducer wheel 44 is located between the first stage impeller and the second water guide bearing 43, between the inducer wheel 44 and the first stage impeller, and the inducer wheel 44 and the second water Between the guide bearings 43, the pump shaft 4 is sleeved on the sleeve 46. This reduces the axial length of the inducer wheel 44, and the processing difficulty of the inducer wheel 4 is greatly reduced.

In the containment spray pump, the function of the inducer wheel 44 is to: increase the pressure of the medium transported by the containment spray pump when passing through the first stage impeller, and ensure the installation of the safety shell spray pump in the nuclear power plant. It is required to meet the requirements of the safety shell spray pump without cavitation under full performance conditions.

The inducer wheel 44 includes a cylindrical hub 441 and an upper conical tapered outer edge 442 disposed on the hub 41. The hub 441 is sleeved on the pump shaft 4, and such a design can increase the overcurrent capability of the containment spray pump, thereby improving the cavitation resistance of the inducer 44 itself. The tapered outer edge 442 is surrounded by two parallel spiral blades. The inlet edges of the two spiral blades are post-swept rounded, thereby further improving the anti-cavitation performance of the induction wheel, thereby improving the anti-cavitation conditions at the outer edge of the outermost cavitation. Even if the initial cavitation occurs at the outer edge of the bottom end of the induction wheel 44, the bubble in the transmission medium is compressed, so that it is condensed and difficult to expand, thereby satisfying the need for pump cavitation performance.

Further, in the present invention, the induction wheel is processed by the casting to replace the original forging; and since the sleeve 46 is provided on the pump shaft 100 at both ends of the inducer 44, the length of the hub 441 of the inducer is originally The 435mm is now changed to 302mm. Therefore, it is only necessary to use the general lathe to process the inducer wheel 44 used in this embodiment. The spiral blade can also obtain the same surface roughness as a five-axis CNC machining center after being ground.

The first water guiding bearing 42 communicates with the impeller outlet of the final stage impeller through a balance hole with the final stage impeller; the second water guiding bearing 43 and the inducer wheel 44 before the induction wheel 44 The outer edge of the inducer wheel is in communication such that a certain pressure difference is formed between the first water guide bearing 42 and the second water guide bearing 43. The containment spray pump can lubricate the first water guide bearing 42 and the second water guide bearing 43 with the medium delivered by the containment spray pump. Although the structure of the first water guiding bearing 42, the second water guiding bearing 43, and the inducer 44 in the present invention has been greatly improved. However, the first water guiding bearing 42, the impeller 41, the connection manner of the inducer wheel 44 and the second water guiding bearing 43 on the pump shaft 4, and the structure of the impeller 41 are still present. There are technologies.

Referring to FIG. 4, the bottom end of the pump shaft 4, that is, the pump shaft 4 below the second water guiding bearing 43, is provided with a shaft head 47, and the shaft head 47 is provided with three disc springs 471 and a lock nut 472, wherein the disc spring 471 can not only effectively lock the pump shaft 4, but also eliminate dimensional changes caused by thermal expansion of various parts of the pump shaft 4 during thermal shock conditions. , and lead to dangerous situations such as locking failure.

Since the medium transported by the containment spray pump is a solution of a radioactive medium, the transport medium contains particles of a large amount of radioactive medium. The particle size of these particles is about 2. 1 mm, and these particles must be filtered to lubricate the first water guiding bearing 42 and the second water guiding bearing 43.

Referring to FIG. 2, in the inner cylinder 1, a top of the water outlet section 12 is provided with a fixing seat 123, and a gap is left between the fixing seat 123 and the pump shaft 4 to allow the safety shell spray pump The transported medium lubricates the first water guide bearing 42 and the second water guide bearing 43. A sanding tray 45 is fixedly mounted on the pump shaft 4, and the sanding tray 45 is located above the fixing base 123. A drainage channel 40 is formed between the bottom surface of the sanding tray 45 and the fixing base 123.

The purpose of the design is that the sanding tray 45 rotates together with the pump shaft 4, and impurity particles larger than the diameter of the drainage channel 40 cannot enter the drainage channel 40, and are smaller than the diameter of the drainage channel 40. After the impurities enter the drainage channel 40, the impurities are ejected under the centrifugal force by the rotation of the sanding tray 45, so that the drainage channel 40 is not blocked, and the first water guide is blocked. The bearing 42 and the second water guiding bearing 43 also fail to fail due to lack of water.

Since a boss is disposed on the top surface of the fixing base 123, and the bottom surface of the sanding tray 45 is provided with a groove, the drainage channel 40 forms a labyrinth drainage channel, which helps to lift the drainage channel 40. Filter effect.

Referring to FIG. 3 , a mechanical seal structure 6 is further disposed between the pump shaft 4 and the upper mounting hole 35 of the pump base 3 . The mechanical seal structure 6 is a self-rinsing mechanical seal structure. a throttle bushing 61 that is sleeved on the inner wall of the upper mounting hole 35 of the pump base 3 and a sealing bushing 62 that is sleeved on the outer wall of the pump shaft 4, the throttle bushing 61 and the The sealing sleeves 62 are sleeved with each other; a spiral mechanical seal 63 is disposed on the outer wall of the sealing sleeve 62. The spiral mechanical seal 63 and the inner wall of the throttle bushing 61 A sealing end face of the mechanical seal structure 6 is formed therebetween.

The purpose of such a design is that the rinsing medium for rinsing the sealing end face of the mechanical seal structure 6 must pass through the hydrocyclone to enter the sealing end face of the mechanical seal structure 6, and flush the seal end face. Since the hydrocyclone can remove foreign particles in the rinsing medium, the foreign particles in the rinsing medium are prevented from entering the sealing end faces of the mechanical sealing structure, resulting in failure of the mechanical sealing structure. Water is diverted from the outlet flange 32 to the hydrocyclone. After the hydrocyclone removes the particles in the medium, the medium for removing impurities is introduced into the mechanical seal structure 6, and the sealing end face is rinsed, and the hydrocyclone filter is filtered. The removed impurities are discharged into the inlet flange 31. The hydrocyclone is only an external device for the containment spray pump and is not part of the containment spray pump.

On the mechanical seal structure 6, above the seal bushing 61, a pressure reducing ring 64 is also fitted over the pump shaft 4. The function of the pressure reducing ring 64 is to effectively limit the leakage of the flushing medium when the mechanical seal structure fails, without affecting the continued operation of the containment spray pump.

Between the bearing body 5 and the mechanical seal structure 6, the pump shaft 4 is also sleeved with a thrust bearing 50, and the thrust bearing 50 is an angular contact ball bearing. Its function is that the balance holes 413 on the impeller 41 together balance the axial force received by the pump shaft 4. The pump shaft 4 and the bearing body 5 are connected at the same time.

The bearing body 5 of a safety shell spray pump of the present invention comprises: a bearing housing 51 and a bearing 52 and an oil cup 53 disposed in the bearing housing 51. The bearing 52 used here is a double row cylindrical roller bearing. The bearing 52 has two specifications higher than the original, so that the bearing 52 can withstand a larger load and the amount of heat generation is reduced. On the other hand, the bearing block 51 is provided with a heat radiating rib, and the total surface area of the heat radiating rib is increased from the original 310 square centimeter to the current 600 square centimeter. Thereby the safety reliability of the bearing component 5 is improved.

In the interior of the inner cylinder 1, between the rear seal ring of the final impeller and the water discharge section 12, a spacer 19 is provided for reinforcing the rigidity of the inner cylinder 1, and stabilizing the The center of rotation of the pump shaft 4.

Between the first water guiding bearing 42 and the radial direction of the pump shaft 4, between the second water guiding bearing 43 and the radial direction of the pump shaft 4, a bearing bushing is disposed; the impeller 41 An impeller bushing is disposed between the pump shaft 4, the bushing 46, the seal bushing 62, the bearing bushing, the impeller bushing and the inducer wheel 44 are all passed through a key and the pump The shaft 4 is sleeved. The sleeve 46, the sealing sleeve 62, the bearing sleeve and the sealing gap of the impeller bushing and the pump shaft 4 are far larger than the deformation of the rotor component and the mating part in the accident condition, ensuring the pump The components on the shaft 4 are in record at the SSE (the location of the nuclear power plant) During and after the major earthquake of intensity), the inner cylinder 1, the pump base 3 and the components on the bearing body 5 do not rub against the pump shaft 4, thereby ensuring the safety of the safety spray pump. Safe operation.

A coupling 48 is provided at the top end of the pump shaft 4 for connecting the motor.

In addition, all the bolts, studs and the like used in the safety shell spray pump of the present invention are secured by a retaining washer. It is guaranteed that the connection between the components of the containment spray pump will not be slack due to vibration under any working condition.

a transmission medium of the containment spray pump flows from the inlet flange 31 into the containment spray pump, filling an outer cavity between the inner cylinder 1 and the outer cylinder 2, the outer cavity a medium in which the medium is introduced into the inner cylinder 1 through the suction pipe 15 at the bottom of the inner cylinder 1, and the inner cylinder is formed by the induction wheel 44 and the multistage impeller 41. The inside 1 rises and finally the safety shell spray pump is discharged from the outlet flange 32. At the same time, lubrication is performed between the pump shaft 4 and the first water guiding bearing 42, the pump shaft 4 and the second water guiding bearing 43.

It should be understood by those skilled in the art that the above embodiments are merely illustrative of the present invention and are not intended to limit the invention, as long as the scope of the present invention is Variations and modifications are intended to fall within the scope of the appended claims.

Claims

Claim

1. A containment spray pump comprising an inner cylinder (1), an outer cylinder (2), a pump base (3), a pump shaft (4) and a bearing body (5);

The pump base is provided with an inlet flange (31), an outlet flange (32), an outer flange (33), an inner flange (34) and an upper mounting hole at the top end of the pump seat (3) (35) The inlet flange (31) communicates with the outer flange (33), the inner flange (34) communicates with the outlet flange (32); the outer flange (33) is fixed at the The outer cylinder (2) is fixed; the inner flange (34) is fixed on the inner cylinder (1), the pump shaft (4) penetrates the bearing body (5), and is installed from the upper a hole (35) extending into the pump seat (3) and extending through the entire inner cylinder (1) from top to bottom; characterized in that:

The inner cylinder (1) includes a flow guiding section (11), a water outlet section (12), a flow guiding shell section (13), a suction section (14) and a suction pipe (15) connected in this order from top to bottom, wherein The flow guiding shell segment (14) is formed by connecting a plurality of stages of flow guiding shells in series;

The pump shaft (4) is sleeved with a plurality of stages of impellers (41) arranged in the axial direction of the pump shaft (4), the impellers (41) of each stage and the flow guiding shell segments (13) The positions of the flow guiding shells of each stage are one-to-one correspondence;

a first flange and a second flange are respectively disposed on upper and lower ends of the outer wall of the flow guiding section (11), and a third flange and a fourth flange are respectively disposed on upper and lower ends of the outer wall of the water outlet section (12) The inner flange (34) on the pump seat (3) is connected to the first flange, and the second flange is connected to the third flange;

a first rib (111) connecting the first flange and the second flange is disposed on an outer wall of the flow guiding section (11), and the outer wall of the water outlet section (12) is connected to the first wall The third flange and the second rib (121) of the fourth flange, the first rib (111) and the second rib (121) are the same number and are even numbers of four or more.

2. A containment spray pump according to claim 1, characterized in that: inside the inner cylinder (1), a third rib is arranged around the inner circumference of the water discharge section (12) (122), on the pump base (3), a fourth rib that is arranged around the circumference of the pump seat (3) and connects the inner flange (34) and the outer flange (33) (36) The number of the first rib (111), the second rib (121), the third rib (122), and the fourth rib (36) is the same.

3. A containment spray pump according to claim 1 or 2, wherein: said pump shaft (4) a first water guiding bearing (42) and a second water guiding bearing (43); wherein the first water guiding bearing

(42) between the pump shaft (4) and the radial direction of the water discharge section (11), the second water guide bearing

(43) is located between the pump shaft (4) and the radial direction of the suction pipe (15).

4. A containment spray pump according to claim 3, wherein: said first water guiding bearing (42) and said second water guiding bearing (43) are hydrostatic bearings, said The first water guiding bearing (42) and the second water guiding bearing (43) are all made of Z2CN18-10 type stainless steel, the first water guiding bearing

(42) and the inner wall of the second water guide bearing (43) are coated with a coating of a nickel-based alloy or a wear resistant material.

5. A containment spray pump according to claim 3, wherein in the inner cylinder (1), a top of the water discharge section (12) is provided with a fixing seat (123); The shaft (4) is fixedly sleeved on the sand tray (45), and the sand tray (45) is located above the fixing seat (123), the top surface of the fixing seat (123) and the sand table (45) A drainage channel (40) is formed between the bottom surfaces.

6. A containment spray pump according to claim 1 or 2, characterized in that: the pump shaft

(4) an induction wheel (44) is also sleeved, the induction wheel (44) being located between the first stage impeller and the second water guiding bearing (43), in the first stage impeller and the inducer wheel Between (44) and the water guide bearing

(43) Sleeve the bushing (46) over the pump shaft (4) between the inducer (44).

7. A containment spray pump according to claim 6, wherein said inducer wheel (44) includes a hub (441) sleeved on said pump shaft (4) and disposed in said Tapered outer edge (442) on the hub (441).

A containment spray pump according to claim 1 or 2, characterized in that a mechanical seal is arranged between the pump shaft (4) and the upper mounting hole (35) of the pump seat (3) Structure (6), the mechanical seal structure (6) includes: a throttle bushing (61) sleeved on an inner wall of the upper mounting hole (35) and a sleeve that is sleeved on an outer wall of the pump shaft (4) a sealing sleeve (62), a spiral seal (63) is disposed on an outer wall of the sealing sleeve (62), and the mechanical seal structure is formed between the spiral seal (63) and the throttle bushing (61) (6) Sealed end face.

9. A containment spray pump according to claim 8 wherein: said bearing body

(5) A thrust bearing (50) is provided between the mechanical seal structure (6).

10. A containment spray pump according to claim 8, characterized in that the bottom end of the pump shaft (4) is provided with a shaft head (47).