An assembly tool for the stationary ring seat of the mechanical seal of the main pump in a nuclear power plant

Abstract

The present invention belongs to the technical field of maintenance engineering for rotating equipment in nuclear power plants, and particularly relates to an assembly tool for the static ring seat of the mechanical seal of the main pump in a nuclear power plant. It is equipped with a lifting plate, which can ensure uniform force during the disassembly and assembly of the static ring seat of the mechanical seal, smoothly rise and fall, avoid the skew of the static ring seat, avoid the risk of damage to equipment and personnel caused by using a hammer, is simple to operate, time-saving and labor-saving, reduces personnel radiation, eliminates the crane operation steps, and saves the construction period.

Description

Technical Field

[0001] This application belongs to the technical field of the overhaul engineering of rotating equipment in nuclear power plants, and particularly relates to an assembly tool for the static ring seat of the mechanical seal of the main pump in a nuclear power plant. Background Art

[0002] At present, M310 units are widely distributed in China. One unit is equipped with three main pumps, and there are more than 30 main pumps of the same type in China. The most frequent defect of this type of main pump is the third-stage mechanical seal. Subsequently, there is the overhaul process of the third-stage mechanical seal. The most complex part of the overhaul of the third-stage mechanical seal occurs during the disassembly and assembly of the static ring seat. When the pin at the lower part of the static ring seat is assembled with the pin hole, only rough scribing can be relied on to determine the position, and the pin hole of the static ring seat often misaligns, resulting in pin damage and a high risk of forced assembly. Summary of the Invention

[0003] The purpose of this application is to provide an assembly tool for the static ring seat of the mechanical seal of the main pump in a nuclear power plant, so as to solve the problems of misalignment of the pin hole of the static ring seat during the assembly of the pin at the lower part of the static ring seat and possible wear of the static ring of the mechanical seal caused by evenly knocking around the static ring seat with a plastic hammer.

[0004] Technical solutions for achieving the purpose of this application:

[0005] The embodiment of this application provides an assembly tool for the static ring seat of the mechanical seal of the main pump in a nuclear power plant. The assembly tool includes: a lifting plate and a positioning assembly;

[0006] The lifting plate is fixed on the upper end face of the static ring seat, and a positioning hole is provided on the upper end face of the lifting plate for installing the positioning assembly;

[0007] The positioning assembly is used to position the relative position between the static ring seat and the mechanical seal housing, so that the pin hole on the lower end face of the static ring seat is aligned with the internal pin of the mechanical seal housing.

[0008] Optionally, the positioning assembly includes: a positioning rod and a positioning frame;

[0009] The positioning rod is fixed on the positioning pin on the upper end face of the outer ring of the mechanical seal housing, and the positioning pin and the internal pin are in a straight line with respect to the center of the circle of the mechanical seal housing;

[0010] One end of the positioning frame is fixed in the positioning hole, and the other end of the positioning frame is sleeved on the positioning rod and can move up and down, so as to align the pin hole on the lower end face of the static ring seat with the internal pin.

[0011] Optionally, the assembly tool further includes: an installation assembly;

[0012] A fixing hole is formed in the center of the lifting plate for fixing the mounting assembly.

[0013] The mounting assembly is used to horizontally mount the static ring seat inside the mechanical seal housing.

[0014] Optionally, the mounting assembly includes a lead screw, a support plate, and two support rods.

[0015] The two support rods are symmetrically fixed on the upper end surface of the outer ring of the mechanical seal housing, and both ends of the support plate are respectively mounted on the two support rods.

[0016] A through hole for passing through the lead screw is provided in the center of the support plate.

[0017] One end of the lead screw is fixed in the fixing hole, and the other end of the lead screw passes through the through hole on the support plate.

[0018] A disassembly nut and a compression nut are mounted on the lead screw; the disassembly nut is arranged on the upper side of the support plate, and the compression nut is arranged on the lower side of the support plate.

[0019] Optionally,

[0020] The length of the lead screw is greater than the length of the support rod.

[0021] Optionally,

[0022] Through holes for passing through the support rods are formed at both ends of the support plate, and the support plate is fixed on the two support rods by nuts arranged on the upper and lower sides.

[0023] Optionally,

[0024] At least two lifting lug holes are further formed on the upper end surface of the lifting plate.

[0025] The two lifting lug holes are symmetrically arranged relative to the center of the lifting plate for hanging lifting lugs.

[0026] Optionally,

[0027] The lifting plate is fixed on the upper end surface of the static ring seat by bolts.

[0028] The beneficial technical effects of this application are as follows:

[0029] (1) The assembly tool for the static ring seat of the main pump mechanical seal in the nuclear power plant provided by the embodiment of this application has a simple structure and is convenient to use. The pins on the outer ring can be used to correspond to the pins inside to achieve precise positioning.

[0030] (2) An assembly tool for the static ring seat of the main pump mechanical seal in a nuclear power plant provided by an embodiment of the present application is equipped with a lifting plate, which can ensure uniform force during the disassembly and assembly of the static ring seat of the mechanical seal, rise and fall smoothly, avoid the skew of the static ring seat, avoid the risk of damage to the equipment and personnel caused by using a hammer, is simple to operate, saves time and effort, reduces personnel radiation, eliminates the crane operation steps, and saves the construction period. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic structural diagram of an assembly tool for the static ring seat of the main pump mechanical seal in a nuclear power plant provided by an embodiment of the present application;

[0032] Figure 2 It is a schematic structural diagram of another assembly tool for the static ring seat of the main pump mechanical seal in a nuclear power plant provided by an embodiment of the present application;

[0033] Figure 3 It is a schematic structural diagram of yet another assembly tool for the static ring seat of the main pump mechanical seal in a nuclear power plant provided by an embodiment of the present application.

[0034] In the figure:

[0035] 1 - Lifting plate; 11 - Positioning hole; 12 - Fixing hole; 13 - Lifting lug hole; 14 - Bolt;

[0036] 2 - Positioning component; 21 - Positioning rod; 22 - Positioning frame;

[0037] 3 - Static ring seat;

[0038] 4 - Mechanical seal housing; 41 - Internal pin; 42 - Positioning pin;

[0039] 5 - Installation component; 51 - Lead screw; 52 - Support plate; 53 - Support rod; 54 - Disassembly nut; 55 - Compression nut. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0040] In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the following described embodiments are only a part of the embodiments of the present application, rather than all of them. Based on the embodiments described in the present application, all other embodiments obtained by those skilled in the art without creative efforts are within the scope of protection of the present application.

[0041] To solve the problems of the prior art, an embodiment of the present application provides an assembly tool for the stationary ring seat of the mechanical seal of the main pump in a nuclear power plant. Since the two pins are on the same straight line, only by aligning the pins on the seal housing can the pins below be accurately positioned at one time. At the same time, the tool is also designed with a pressing plate that can press the entire stationary ring seat flat, avoiding the use of a hammer; during disassembly, bolts are also used to symmetrically pull out, ensuring a stable process and balance, and also eliminating the use of a hammer.

[0042] Based on the above, to clearly and detailedly illustrate the above advantages of the present application, the following will describe the specific embodiments of the present application with reference to the accompanying drawings.

[0043] See Figure 1 , which is a schematic structural diagram of an assembly tool for the stationary ring seat of the mechanical seal of the main pump in a nuclear power plant provided by an embodiment of the present application.

[0044] An assembly tool for the stationary ring seat of the mechanical seal of the main pump in a nuclear power plant provided by an embodiment of the present application includes: a lifting plate 1 and a positioning assembly 2;

[0045] The lifting plate 1 is fixed on the upper end surface of the stationary ring seat 3, and a positioning hole 11 is provided on the upper end surface of the lifting plate 1 for installing the positioning assembly 2;

[0046] The positioning assembly 2 is used to position the relative position between the stationary ring seat 3 and the seal housing 4, so that the pin hole on the lower end surface of the stationary ring seat 3 is aligned with the internal pin 41 of the seal housing 4.

[0047] In some possible implementation manners of the embodiment of the present application, the positioning group 2 may specifically include: a positioning rod 21 and a positioning frame 22;

[0048] The positioning rod 21 is fixed on the positioning pin 42 on the upper end surface of the outer ring of the seal housing 4, and the positioning pin 42 and the internal pin are in a straight line with respect to the center of the circle of the seal housing 4;

[0049] One end of the positioning frame 22 is fixed in the positioning hole 11, and the other end of the positioning frame 22 is sleeved on the positioning rod 21 in a vertically movable manner, for aligning the pin hole on the lower end surface of the stationary ring seat 3 with the internal pin 41.

[0050] An embodiment of the present application provides an assembly tool for the stationary ring seat of the mechanical seal of the main pump in a nuclear power plant. The positioning rod 21 and the positioning frame 22 are directly installed on the lifting plate 1 of the stationary ring seat 3. The lower part of the positioning rod 21 is directly inserted into the positioning pin 42 of the seal housing 4, and the positioning rod 21 can slide up and down in the hole of the positioning frame 22 to ensure that the pin hole on the stationary ring seat 3 and the internal pin 41 can be accurately matched during the stable descent of the stationary ring seat 3.

[0051] In one example, at least two lifting lug holes 13 are further formed on the upper end surface of the lifting plate 1;

[0052] The two lifting lug holes 13 are symmetrically arranged with respect to the center of the lifting plate 1 and are used for hanging the lifting lugs.

[0053] In one example, the lifting plate 1 is fixed to the upper end surface of the stationary ring seat 3 by bolts 14.

[0054] In addition, the inventors of the present application found in the research that there are still the following problems in the existing assembly method of the stationary ring seat: The assembly method is that a crane hangs the stationary ring seat, levels it and then places it on the mechanical seal housing, and evenly taps the periphery of the stationary ring seat with a plastic hammer to embed the stationary ring seat into the third-stage mechanical seal housing. However, the stationary ring seat often shifts during the descent process, resulting in inconsistent descent heights around it and the phenomenon of the stationary ring seat getting stuck. Similarly, during disassembly, the mechanical seal housing is evenly tapped with a plastic hammer while the crane lifts the stationary ring seat, so that the stationary ring seat is separated from the mechanical seal housing. However, the static and dynamic rings of the mechanical seal are precision equipment, and it is inevitable to make mistakes during the process of tapping with a hammer, which may cause wear of the static ring of the mechanical seal; subsequent maintenance of the mechanical seal has a certain amount of radioactivity. After problems occur in the assembly, it is necessary to disassemble and then reassemble, which is not only time-consuming and laborious, but also has a certain risk.

[0055] Therefore, in some possible implementation manners of the embodiments of the present application, as Figure 2 shown, the assembly tool for the stationary ring seat of the main pump mechanical seal of a nuclear power plant may further include: a mounting assembly 5;

[0056] A fixing hole 12 is formed in the center of the lifting plate 1 for fixing the mounting assembly 5;

[0057] The mounting assembly 5 is used to horizontally mount the stationary ring seat 3 inside the mechanical seal housing 4.

[0058] In some possible implementation manners of the embodiments of the present application, the mounting assembly 5 may specifically include: a lead screw 51, a support plate 52 and two support rods 53;

[0059] The two support rods 53 are symmetrically fixed to the upper end surface of the outer ring of the mechanical seal housing 4, and both ends of the support plate 52 are respectively mounted on the two support rods 53;

[0060] A through hole for passing through the lead screw 51 is provided in the center of the support plate 52;

[0061] One end of the lead screw 51 is fixed in the fixing hole 12, and the other end of the lead screw 51 passes through the through hole on the support plate 52;

[0062] A disassembly nut 54 and a compression nut 55 are mounted on the lead screw 51; the disassembly nut 54 is arranged on the upper side of the support plate 52, and the compression nut 55 is arranged on the lower side of the support plate 52.

[0063] In one example, the length of the lead screw 51 is greater than the length of the support rod 53.

[0064] Refer to Figure 3 , it should be noted that the process of installing the stationary seal seat 3 is as follows:

[0065] Place the mechanical seal housing 4 on the assembly platform, install the positioning frame 22 onto the lifting plate 1, install the lifting plate 1 and the stationary seal seat 3 together, install the support plate 52 and the support rod 53 in place as well, fix the positioning rod 21 on the positioning pin 42 at the upper end face of the outer ring of the mechanical seal housing 4, slowly turn the compression nut 55, screw the compression nut 55 under the support plate 52, continue to tighten the compression nut 55, so that the lifting plate 1 slowly presses down the stationary seal seat 3. This process can ensure that the stationary seal seat 3 is slowly and smoothly pressed down to achieve the purpose of assembly.

[0066] The process of disassembling the stationary seal seat 3 is as follows:

[0067] Place the mechanical seal housing 4 on the assembly platform, install the lifting plate 1 and the stationary seal seat 3 together, install the support plate 52 and the support rod 53 in place as well, slowly turn the disassembly nut 54, screw the disassembly nut 54 above the support plate 52, continue to tighten the disassembly nut 54, so that the lifting plate 1 slowly raises the stationary seal seat 3 to achieve the purpose of disassembly.

[0068] In some possible implementation manners of the embodiments of the present application, through holes for passing through the support rod 53 are provided at both ends of the support plate 52, and the support plate 52 is fixed on the two support rods 53 by nuts provided on the upper and lower sides.

[0069] The embodiments of the present application provide an assembly tool for the stationary seal seat of the main pump mechanical seal of a nuclear power plant. The positioning rod and the positioning frame are directly installed on the lifting plate of the stationary seal seat, and the lower part of the positioning rod is directly inserted into the positioning pin of the mechanical seal housing. The positioning rod can slide up and down in the hole of the positioning frame to ensure that the pin hole on the stationary seal seat and the positioning pin can be accurately matched during the smooth descent of the stationary seal seat. In addition, a special disassembly and assembly bracket is designed, which is fixed on the outer ring of the mechanical seal through two lead screws and the support plate, and is connected to the lifting plate through a lead screw in the middle. There is a nut on each of the upper and lower sides of the support plate. By adjusting the nut, the up and down movement of the stationary seal seat can be controlled, eliminating the process of using a plastic hammer and also saving the occupancy time of the crane.

[0070] Next, in combination with a specific example, the installation method of an assembly tool for the stationary seal seat of the main pump mechanical seal provided by the embodiments of the present application will be described in detail.

[0071] Refer to Figure 3 , the installation method of an assembly tool for the stationary seal seat of the main pump mechanical seal provided by the embodiments of the present application is as follows:

[0072] Step 1: Fix the lifting plate 1 to the stationary ring seat 3 with four bolts 14;

[0073] Step 2: Use a crane to lift the lifting plate 1 together with the stationary ring seat 3 to the upper part of the mechanical seal housing 4 through the lifting lugs, and keep an appropriate distance;

[0074] Step 3: The positioning pin 42 is directly installed on the upper end face of the mechanical seal housing 4. The positioning pin 42 is inserted into the positioning rod 21. Then slowly place the stationary ring seat 3 on the mechanical seal housing 4 and remove the lifting lugs on the lifting plate 1;

[0075] Step 4: The positioning frame 22 is fixed to the upper part of the lifting plate 1 with screws. The positioning rod 21 is directly inserted into the positioning frame 22 and can slide up and down;

[0076] Step 5: Install two support rods 53 on the mechanical seal housing 4. The support plate 52 is fixed to the support rods 53 with upper nuts and lower nuts;

[0077] Step 6: The lead screw 51 is fixed to the lifting plate 1 by threads and then fixed with nuts;

[0078] Step 7: The compression nut 55 is screwed onto the lead screw 52 and installed below the support plate 52. The disassembly nut 54 is screwed onto the lead screw 51 and installed above the support plate 52.

[0079] The above has described the present application in detail with reference to the accompanying drawings and embodiments. However, the present application is not limited to the above embodiments. Within the scope of knowledge possessed by those of ordinary skill in the art, various changes can be made without departing from the purpose of the present application. The content not described in detail in the present application can all adopt the prior art.

Claims

1. An assembly tool for the stationary ring seat of the mechanical seal of the main pump in a nuclear power plant, characterized in that, the assembly tool includes: a lifting plate and a positioning assembly; the lifting plate is fixed on the upper end face of the stationary ring seat, and a positioning hole is provided on the upper end face of the lifting plate for installing the positioning assembly; the positioning assembly is used to position the relative position between the stationary ring seat and the mechanical seal housing, so that the pin hole on the lower end face of the stationary ring seat is aligned with the internal pin of the mechanical seal housing; the positioning assembly includes: a positioning rod and a positioning frame; the positioning rod is fixed on the positioning pin on the upper end face of the outer ring of the mechanical seal housing, and the positioning pin and the internal pin are in a straight line with respect to the center of the mechanical seal housing; one end of the positioning frame is fixed in the positioning hole, and the other end of the positioning frame is sleeved on the positioning rod in a vertically movable manner, for aligning the pin hole on the lower end face of the stationary ring seat with the internal pin.

2. The assembly tool for the stationary ring seat of the mechanical seal of the main pump in a nuclear power plant according to claim 1, characterized in that, the assembly tool further includes: an installation assembly; a fixing hole is provided at the center of the lifting plate for fixing the installation assembly; the installation assembly is used to horizontally install the stationary ring seat inside the mechanical seal housing.

3. The assembly tool for the stationary ring seat of the mechanical seal of the main pump in a nuclear power plant according to claim 2, characterized in that, the installation assembly includes: a lead screw, a support plate and two support rods; the two support rods are symmetrically fixed on the upper end face of the outer ring of the mechanical seal housing, and both ends of the support plate are respectively installed on the two support rods; a through hole for passing through the lead screw is provided at the center of the support plate; one end of the lead screw is fixed in the fixing hole, and the other end of the lead screw passes through the through hole on the support plate; a disassembly nut and a compression nut are installed on the lead screw; the disassembly nut is arranged on the upper side of the support plate, and the compression nut is arranged on the lower side of the support plate.

4. The assembly tool for the stationary ring seat of the mechanical seal of the main pump in a nuclear power plant according to claim 3, characterized in that, the length of the lead screw is greater than the length of the support rod.

5. The assembly tool for the stationary ring seat of the mechanical seal of the main pump in a nuclear power plant according to claim 3, characterized in that, through holes for passing through the support rods are provided at both ends of the support plate, and the support plate is fixed on the two support rods by nuts arranged on the upper and lower sides.

6. The assembly tool for the stationary ring seat of the mechanical seal of the main pump in a nuclear power plant according to claim 1, characterized in that, at least two lifting lug holes are further provided on the upper end face of the lifting plate; the two lifting lug holes are symmetrically arranged relative to the center of the lifting plate for hanging lifting lugs.

7. The assembly tool for the stationary ring seat of the mechanical seal of the main pump in a nuclear power plant according to claim 1, characterized in that, the lifting plate is fixed on the upper end face of the stationary ring seat by bolts.

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