JPH0441275Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a vertical shaft multi-stage pump made of sheet metal, and is particularly suitable for use as a submersible motor pump.

(Prior art) In general, casting operations have a poor working environment and the weight of the product is heavy, so there is a tendency to gradually manufacture components by sheet metal processing, and vertical shaft multistage pumps such as submersible motor pumps are also manufactured by sheet metal molding. It is becoming more and more common.

FIG. 4 is a vertical cross-sectional view of a conventional submersible motor pump formed by sheet metal molding as described above, in which a rotating shaft (pump shaft) 10 is shared in common above the motor 1, and a strainer 2 is inserted in a multi-stage manner. A pump part is formed, and the multi-stage pump part is joined by a suction casing 3, a lower casing 4, an intermediate casing 5, an upper casing 6, and a valve casing 7, all of which are formed by sheet metal, stacked on top of each other. The upper end of the valve casing 7 and the lower end of the strainer 2 are integrally connected by fastening them with a plurality of belt-shaped bands 8. Inside the lower casing 4 and the intermediate casing 5, there is a sheet metal impeller 9 fixed to the pump shaft 10, and a sheet metal guide vane 11 that guides water discharged from the impeller to the inlet of the next impeller. are stored in each. The liner portion 9a of the impeller 9 is connected to the liner ring 13 attached to the liner ring case 12.
Keep it supported. In the figure, 14 is an intermediate bearing, 15 is an upper bearing, 16 is a valve body, and 17 is a valve seat.

FIG. 2 is an enlarged vertical cross-sectional view of a pump part similar to the pump part shown in FIG. 4, in which there are three stages of impellers. The lower pump casing 4 is formed by sheet metal molding, and its lower end is bent inward as shown in 4a.
Further, the upper end is bent diagonally inward like 4b to form the upper plate of the guide vane 11, and the liner ring case 12 holding the rubber liner ring 13 is welded 12a to the upper plate 4b of the guide vane 11. The outer circumferential portion of the liner ring case 12 is provided with a cavity into which an inner bent portion 5a formed at the lower end of the next stage pump casing 5 can be fitted. Both the intermediate pump casing 5 and the lower pump casing 5 are formed in exactly the same manner as the lower pump casing 4, and the inwardly bent portion 5a formed at the lower end is connected to the liner ring case of the lower pump casing 4. 12 are fitted into a cavity formed on the outer periphery and are connected to each other. In the figure, 9a indicates a wedge that fixes the impeller 9 to the pump shaft 10.

When the submersible motor pump configured as described above is driven underwater, water is sucked into the lowermost impeller 9 through the strainer 2, and is sequentially sent to the upper impellers. However, when looking at the flow of the pumped liquid discharged from each impeller, as shown in the figure, the pumped liquid discharged from the impeller 9 is divided into two parts, and most of it passes through the guide vane 11 to the inlet of the next stage impeller. However, a part of the liquid flows into the bag-shaped portion 15 formed between the pump casing 5 and the outside of the liner ring case 12 and forms a vortex. If a large amount of slurry component is contained in the bag-shaped portion 15, it cannot escape from the bag-shaped portion 15, and the impeller 9
As the slurry component rotates, as shown in Figure 3, which is an enlarged view of part A in Figure 2, the inner wall of the casing, especially near the bent part at the lower end of the casing body, wears out as shown in w, and the final The main drawback was that it caused holes in the casing.

On the other hand, as shown in FIG. 5, the liner ring case 12 in the conventional case is extended along the impeller 9 to form a guide member (vane) 16 so as to cover the bag-shaped portion 15. A multistage pump in which the outer edge of the guide member 16 is directly attached to the inner surface of the intermediate casing 5 is also known. In the figure, 17 indicates a partition plate of the intermediate casing 5 that slopes upward toward the pump shaft 10, and Wa indicates residual water when the pump is stopped.

(Refer to Utility Model Publication No. 58-42636 (Fig. 3)) (Problems to be solved by the invention) As described above, the guide member 16 is formed by extending the liner ring case 12, compared to the conventional one. (Fig. 2), the bag-shaped portion 15 is
6, the formation of the vortex as described above is prevented. However, those with the above structure (fifth
In Figure), when assembling the multistage pump, when each impeller 9 is sequentially attached to the pump shaft from above, the impeller 9 is attached to the shaft 10 inside the intermediate casing 5 to which the guide member 16 is integrally attached. For example, it is necessary to install the impeller 5 correctly on the pump shaft 10 while checking the fitting state between the liner part 9a of the impeller 9 and the liner ring 13 attached to the casing 5. There were problems such as difficulty in fixing it in place.

The technical problem of the present invention is to solve the above problems.

(Means for Solving the Problems) In order to solve the problems of the prior art described above, the present invention provides a liner ring provided opposite to the impeller liner portion, and a liner ring case to which the liner ring is attached. , a rectifying plate provided on the outside of the liner ring case is attached to the upper plate with the upper end of each pump casing bent inward, and a rectifying plate provided on the outside of the liner ring case is installed between the rectifying plate and the inner wall surface of the pump casing. The pump casing is characterized in that a baffle is attached to the inner wall of the lower end of the next stage, that is, the upper stage pump casing adjacent to the upper end, and the inside diameter of the buffle is larger than the outside diameter of the impeller.

(Function) With the above configuration, the outer side of the liner ring case 12 and the next stage pump casing 5
The inlet of the bag-shaped part (15 in Fig. 2) that was conventionally formed between the inner wall and the inner wall is closed by the rectifying plate 21 and the buttful 22, so that the air discharged from the impeller is The vortex that was conventionally formed by a part of the pumped liquid is no longer generated, and the slurry components contained in the pumped liquid are difficult to enter this area.
The rotational energy of the impeller is difficult to be transmitted to the bag-shaped portion by the baffle 22 and the current plate 21.

In addition, the present invention has a bag-shaped portion (second
Since the guide member covering 15) in the figure is formed by the rectifier plate 21 and the baffle 22 that are separately attached to the upper and lower ends of the adjacent pump casings, it is possible to assemble the multi-stage pump. Therefore, when assembling the pump casings sequentially starting from the lower stage, each impeller is assembled with the pump casing of the stage one stage lower than the stage to which the impeller belongs, that is, the pump of the stage number to which the impeller belongs. In the open state before assembling the casing (that is, the pump casing that houses the impeller),
Fixed to the pump shaft. That is, a liner ring 13, a liner ring case 12, and a current plate 2 are provided at the upper end.
After assembling the pump casing 4 which is one step lower and which has the impeller 9-2 integrally attached to the pump casing 4, the impeller 9-2 is pumped from above while checking the fitting condition between the liner ring 12 and the impeller liner portion 9a. Insert it into the shaft and fix it, then insert the pump casing 5 of the number of stages to which the impeller 9-2 belongs from above,
The already assembled pump casing 4 of one stage lower is joined and assembled. At this time, since the inner diameter of the buttful 22 attached to the inner wall of the lower end of the pump casing 5 of the relevant number of stages is made larger than the outer diameter of the impeller 9-2, the above-mentioned insertion work may be hindered. does not occur. Similarly, each pump casing is assembled in turn.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional view of the main parts of a vertical shaft multi-stage pump showing one embodiment of the present invention, and among the reference numerals shown in this figure, the same reference numerals as shown in FIG. 2 indicate the same or similar parts. shall be taken as a thing. In the figure, the lower pump casing 4, which is molded from sheet metal, has its lower end bent inward to form a bent portion 4a, and its upper end bent diagonally to form an upper plate 4b of the guide vane 11. 4b, a space is formed on the outer periphery into which the bent part 5a at the lower end of the next stage casing can be fitted, and the liner ring case 12 is fixed by welding 12a, and the next stage pump casing 5 is inserted into the space. The structure is similar to the conventional one (Fig. 2) in that both pump casings 4 and 5 are connected by fitting and fixing the lower end bent portion 5a of the pump, and each pump casing is connected in the same manner. .

In this embodiment, the liner ring case 12
A rectifier plate 21 bent outward so as to be substantially parallel to the impeller 9 is attached to the outside of the impeller 9 by welding its base 21a, and furthermore, a gap between the rectifier plate 21 and the next stage pump casing wall 5 is attached. One end of the buttful 22 is fixed to the inner wall of the next-stage pump casing 5 by welding, and the other end is joined to the end of the lower end bent portion 5a. Note that other intermediate pump casings are assembled and connected in exactly the same manner.

According to this embodiment, the front surface (inlet part) of the bag-like part 15 on the outside of the liner ring case, which was formed in the conventional one (FIG. 2), is closed by the rectifying plate 21 and the buttful 22. Therefore, part of the pumped liquid discharged from the impeller is prevented from entering the bag-shaped portion. Therefore, the slurry components contained in the pumped liquid are also difficult to enter into this area, so that the wear of the pump casing as in the conventional pump (FIG. 3) does not occur. In addition, the rotational energy of the impeller 9 is less likely to be transmitted to the bag-shaped portion by the baffle 22 and the rectifier plate 21, so energy loss is reduced accordingly, and all of the pumped liquid from the impeller is smoothly transferred to the next stage impeller. There is no need for unnecessary exercise in order to go to the car, which improves pump efficiency.

On the other hand, when assembling the multistage pump, the pump casings are joined in sequence starting from the lower pump casing.
In the one shown in FIG. 1, the lowermost pump casing 4 is first inserted into the rotating shaft 10 from above.
At this time, the illustrated lowermost impeller 9-1 has already been attached to the pump shaft 10. Lowermost pump casing 4 inserted from above as above
The liner ring 13, liner ring case 12, and current plate 21 are integrally attached to the upper end, and it is checked whether the liner ring 13 and the impeller liner portion 9a are properly fitted. Meanwhile, the impeller 9-2 inserted into the pump shaft 10 from above is fixed to the pump shaft 10 using a separately prepared jig with a taper collet 19a.

Next, the intermediate casing 5, which is integrally formed by welding the liner ring 13, the ring case 12, the rectifying plate 21, and the guide vane 11 to the upper end and the buttful 22 to the inner wall of the lower end, is inserted from above,
The outer periphery of the liner ring case 12 attached to the front or lowermost pump casing 4 is fitted into the lower bent portion 5a of the casing 5, and the intermediate casings 4 and 5 are joined at the correct position. When inserting this intermediate casing 5, since the inner diameter of the baffle 22 is formed slightly larger than the outer diameter of the impeller 9-2, the intermediate casing 5 can be inserted passing through the outside of the impeller. After sequentially assembling in the same manner, the upper surface of the uppermost valve casing and the strainer at the lower end are fastened together with several belt-like bands 8, as shown in Fig. 4, thereby making each stage of casings strong. be integrated. In addition, when disassembling, the above procedure may be reversed. In this way, assembly and disassembly can be easily carried out without any hindrance.

In the above embodiment, the direction of the current plate 21 is formed almost parallel to the impeller, but it is not necessarily limited to this direction, and the point is that the pumped liquid discharged from the impeller enters the outside of the liner ring case. Instead, it is sufficient to prevent the formation of vortices in the area.

In addition, this invention is not only applicable to submersible motor pumps.
Of course, it can be widely used as a vertical shaft multi-stage pump.

(Effects of the invention) As explained above, according to the invention, by providing a rectifier plate and a buttful attached to the inner wall of the next stage casing on the outside of the liner ring case, the flow rate of discharge from the impeller is reduced. Part of the pumped liquid is prevented from flowing to the outside of the lining case,
There is no risk that the slurry contained in the pumped liquid will rotate inside the casing due to the rotational energy of the impeller and wear out the inner wall of the casing.

In addition, all of the pumped liquid discharged from the impeller is smoothly guided to the inlet of the impeller of the next stage, and there is no wasted movement due to vortex flow, so pump efficiency is improved.

In addition, the guide member that covers the bag-shaped portion that forms the vortex is installed between a rectifying plate attached to the upper end of the adjacent lower pump casing and a buttful attached to the inner wall of the lower end of the next (upper) pump casing. By dividing the impeller and forming the inner diameter of the buttful larger than the outer diameter of the impeller, when assembling the multi-stage pump, the impeller can be attached to the pump shaft in an open state before assembling the pump casing that houses the impeller. Installation can be fixed. Therefore, the pump can be assembled accurately and easily, and the pump can also be disassembled easily.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of essential parts of a vertical multi-stage pump showing an embodiment of the present invention, FIG. 2 is a similar cross-sectional view of a conventional pump, and FIG. 3 is an enlarged cross-sectional view of section A in FIG. Figure 4 is a vertical cross-sectional view of a conventional submersible motor pump;
The figure is a sectional view of a main part showing a conventional example. 4,5...Pump casing, 9,9-1,9
-2,9-3... Impeller, 9a... Liner part, 1
0...Pump shaft, 12...Liner ring case,
13... liner ring, 21... rectifier plate, 22...
...Batsuful.

Claims (1)

[Scope of utility model registration request] A liner ring case 12 with a liner ring 13 installed facing the impeller liner portion 9a.
In the vertical shaft multistage pump formed by sheet metal with a rectifying plate 21 provided on the outside of the liner ring 13,
The liner ring case 12 and the rectifying plate 21 are integrated and attached to the upper plates 4b and 5b, which have the upper ends of each pump casing 4 and 5 bent inward, so that the rectifying plate 21 and the inner wall surface of the pump casings 4 and 5 are connected to each other. In between, there is provided a buttful 22 attached to the inner wall of the lower end of the next pump casing adjacent to the upper end of the pump casing, and the inner diameter of the buttful 22 is larger than the outer diameter of the impellers 9-1 and 9-2. Vertical shaft multi-stage pump.