A shaft positioning device for disassembly and assembly of water pumps in nuclear power plants

Abstract

The present invention relates to a shaft positioning device for disassembling and assembling a water pump in a nuclear power plant. The shaft positioning device is in the shape of a disc. A fixing bolt hole and a shaft head threaded hole are arranged on the disc structure. The shaft head threaded hole is located at the center of the disc. The fixing bolt hole is a long slot type and is evenly distributed in a radial shape around the center of the disc. The shaft positioning device includes at least 4 fixing bolt holes. The fixing bolt holes and the shaft head threaded holes are through holes. A truncated cone-shaped protrusion is arranged around the shaft head threaded hole. Compared with the prior art, the present invention has the advantages of good stability, high measurement accuracy, convenient and quick operation, and a wide range of applications.

Description

Technical Field

[0001] The invention relates to a special tool for disassembling and locating a pump shaft system, in particular to a shaft system positioning device used for disassembling and locating a water pump in a nuclear power plant. Background Art

[0002] There are many vertical long-shaft submersible water pumps in nuclear power plants. These pumps are generally composed of multiple shafts, which are connected by coupling short sections. A guide bearing is set at the intermediate shaft, and the impeller is fixed to the end shaft by an adapter sleeve. The current method of shaft positioning is to measure and locate by placing a ruler on the suction flange surface, or to mark the impeller adapter sleeve. These two methods have the following problems:

[0003] 1). Low measurement accuracy of the shaft installation position affects the relative position of the impeller on the shaft and the output of the pump;

[0004] 2). It affects the coordination between the chrome plating position on the shaft and the guide bearing position, and the maintenance quality is difficult to guarantee. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and provide a shaft positioning device for disassembly and assembly of water pumps in nuclear power plants.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] A shaft positioning device for disassembling and assembling a water pump in a nuclear power plant is provided. The shaft positioning device is disc-shaped and provided with fixing bolt holes and shaft head threaded holes. The fixing bolt holes are long slot fixing bolt holes and are evenly distributed in a radial shape around the center of the disc.

[0008] The shaft head threaded hole is located at the center of the disc.

[0009] The shaft system positioning device comprises at least 4 fixing bolt holes.

[0010] The shaft head threaded hole is surrounded by truncated cone-shaped protrusions.

[0011] The thickness of the truncated cone-shaped protrusion is 10 mm.

[0012] The long slot type fixing bolt hole is 21 mm wide and 91 mm long, and the shaft head threaded hole is a circular hole with a radius of 36 mm.

[0013] The fixing bolt hole and the shaft head threaded hole are both through holes.

[0014] Compared with the prior art, the present invention has the following advantages:

[0015] 1) Good stability and high measurement accuracy: This tool can contact the equipment accurately and reliably, ensuring the accuracy of the measurement;

[0016] 2) Easy and quick operation: This special tool has a simple structure, small size, light weight, and can be quickly installed and used;

[0017] 3) Wide application range: Due to the setting of long slot type fixing bolt holes, the device can be applied to water pumps of various sizes. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the shaft system positioning device used for disassembly and assembly of water pumps in nuclear power plants according to the present invention;

[0019] Figure 2 is a cross-sectional view of the shaft system positioning device of the present invention;

[0020] Figure 3 It is a schematic diagram of the shaft system positioning device of the present invention when it is actually used;

[0021] Among them, 1. threaded hole of shaft head; 2. fixing bolt hole; 3. truncated cone-shaped protrusion; 4. shaft positioning device; 5. fixing bolt; 6. suction port; 7. guide casing; 8. impeller. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0023] Example

[0024] A shaft positioning device for disassembling and assembling a water pump in a nuclear power plant is in the shape of a disc. A fixing bolt hole 2 and a shaft head threaded hole 1 are arranged on the disc structure. The shaft head threaded hole 1 is located at the center of the disc. The fixing bolt hole 2 is a long groove type and is evenly distributed in a radial shape around the center of the disc. Figure 1 shown.

[0025] The shaft system positioning device comprises at least four fixing bolt holes 2. The fixing bolt holes and the shaft head threaded holes are all through holes.

[0026] There are truncated cone-shaped protrusions 3 around the threaded hole of the shaft head. Figure 2 as shown in .

[0027] The thickness of the truncated cone protrusion is 10mm, and the outer radius of the truncated cone protrusion is 46mm. The width of the long slot type set bolt hole is 21mm, the length is 91mm, and the radius of the shaft head threaded hole is 36mm. The overall radius of the disc is 165mm.

[0028] How to use:

[0029] 1) Install the shaft positioning device 4 on the pump suction port and secure it with four fastening bolts 5 (such as Figure 3 shown);

[0030] 2) Insert the impeller shaft (the lowest shaft of the shaft system) from the suction port side and screw it into the threaded hole of the shaft system positioning device 4 (such as Figure 3 shown);

[0031] 3) Measure the distance between the end face of the shaft positioning device 4 and the shaft head to make it consistent with the measurement data before disassembly;

[0032] 4) Connect the suction port 6 and the guide shell 7, put the impeller 8 into the guide shell 7, fix it with a tightening sleeve, and install other impellers in the same way. At this point, the position of the impeller on the shaft is completed;

[0033] 5) Disassemble the shaft positioning device 4.

[0034] The drum net flushing water pump used in nuclear power plants is a typical vertical long-axis submersible water pump. During the installation or disassembly of the drum net flushing water pump, the entire shaft system cannot be accurately positioned in the equipment, resulting in no reference data to guide the reinstallation work after the equipment is disassembled. This shaft system positioning device can accurately and reliably position the shaft system, thereby ensuring the installation position of the impeller.

[0035] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A shaft positioning device for disassembling and assembling a water pump in a nuclear power plant, characterized in that: The shaft system positioning device is in the shape of a disk, and a fixing bolt hole (2) and a shaft head threaded hole (1) are provided on the disk structure. The fixing bolt hole (2) is a long slot type fixing bolt hole and is evenly distributed in a radial shape around the center of the disk. The shaft head threaded hole (1) is located at the center of the disc; The shaft system positioning device comprises at least four fixing bolt holes (2); The method for using the shaft system positioning device comprises: 1) Install the shaft positioning device (4) at the pump suction port and secure it with four fastening bolts (5); 2) Insert the impeller shaft from the suction port side and screw it into the shaft head threaded hole (1) of the shaft positioning device (4); 3) Measure the distance between the end face of the shaft positioning device (4) and the shaft head to make it consistent with the measurement data before disassembly; 4) Connect the suction port (6) and the guide casing (7), place the impeller (8) into the guide casing (7), and fix it with a tightening sleeve. Install other impellers in the same way. At this point, the impeller is positioned on the shaft. 5) Disassemble the shafting positioning device (4); The threaded hole of the shaft head is surrounded by truncated cone-shaped protrusions (3); The truncated cone-shaped protrusion (3) has a thickness of 10 mm; The long slot type fixing bolt hole is 21mm wide and 91mm long, and the threaded hole on the shaft head is a circular hole with a radius of 36mm; The fixing bolt hole (2) and the shaft head threaded hole (1) are both through holes.

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