JPS6363758B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a casing tightening device for a slim submersible pump.

Generally, small submersible pumps are used in cases where the pumping process is relatively long, such as in deep wells, and they are constructed by connecting multiple unit pump elements in series, so the weight load on the pump casing is large. Therefore, the pump casing must be tightly tightened.

For this reason, conventionally, as shown in FIG. 3, in a system in which a plurality of unit pump elements 1 are arranged in tandem and a lower casing 2 and a discharge casing 3 are arranged at both ends, one end of the tightening band 4 is It is fixed to the lower casing 2 with a screw 5, a bolt 6 provided at the other end of the tightening band 4 is passed through a hole in the discharge casing 3, and is tightened with a nut 7, and the lower casing 2 and the discharge casing 3 form a plurality of units. The pump element 1 was under pressure.

However, in such a configuration, since the tightening band 4 protrudes outward, it may be difficult to insert it into a narrow well hole. Furthermore, since the casing of the unit pump element 1 is exposed, there is a problem that the product value will be lowered unless the casing is finished well. Recently, due to the development of materials, the casing of the unit pump element 1 is sometimes made of synthetic resin, and the appearance of such a synthetic resin casing also reduces the commercial value.

For this reason, a system has been developed in which a cylindrical body 8 made of metal is used to tighten the lower casing 2 and the discharge casing 3, as shown in FIG.
This cylindrical body 8 has thread grooves 9 and 10 formed inside both ends. First, the thread groove 9 is screwed into the threaded part provided on the outer periphery of the lower casing 2, and then the upper thread groove 10 is inserted into the discharge casing 3. The unit pump element 1 is tightened by the lower casing 2 and the discharge casing 3.

According to this configuration, since the unit pump element 1 inside is covered by the cylindrical body 8, the unit pump element 1
There is no need to clean the exterior finish of the
Although the commercial value is improved, there is a problem in that the threaded connection of the cylindrical body 8 becomes loose due to intense vibration during pump operation. Therefore, after the thread grooves 9 and 10 of the cylindrical body 8 were screwed onto the outer peripheries of the lower casing 2 and the discharge casing 3, they were screwed together with fixing screws 11 and 12.

Therefore, tap-cutting work is required to attach the fixing screws 11 and 12, which is not easy. In addition, a pipe wrench must be used to tighten the screws of the cylindrical body 8, and the cylindrical body 8
is dented by the pipe wrench, reducing the product value. On the other hand, it is possible to make the cylindrical body 8 thick so as not to be dented, but if the outer diameter is constant, the inner diameter will be reduced by the wall thickness, and the diameter of the unit pump element will also be smaller, that is, the diameter of the blade will also be smaller. As the pump becomes smaller, the output decreases, and the number of stages in the unit pump element must be increased.

Furthermore, when disassembled after many years of use, it becomes difficult to remove the fixing screws 11 and 12 due to rust, etc.
Since the cylindrical body 8 is tightly screwed together, it is difficult to remove it.
Then, when reassembling, fixing screws 11 and 12
There is a problem that the position of the hole for screwing together is not accurate.

Furthermore, when the discharge casing 3 is rotated and tightened, the casing of the unit pump element 1 inside also rotates by friction, and force is applied not only in the vertical direction but also in the radial direction, and the fitting gap of the unit pump element 1 in each stage is limited in one direction. The sliding parts of the rotating part and the fixed part accumulate tolerances at each stage, making it impossible to maintain an appropriate gap and causing them to rub against each other and slide, causing problems in starting. In addition, 13 in FIG. 4 is a bearing casing, 14 is a check valve, and 15 is a discharge part.

The present invention takes these problems into consideration, and aims to provide a slim submersible pump using a cylindrical body for the tightening member, which is easy to assemble and maintain, and has good characteristics. The basic structure of the present invention to achieve the above object is that a lower casing and a discharge casing are arranged at the lower and upper ends of a plurality of unit pump elements arranged in tandem, and both casings are tightened using a cylindrical body. , the thread groove inside the lower part of the cylindrical body is screwed into the threaded part of the lower casing, a member is fixed inside the upper part of the cylindrical body, and this member and the discharge casing are tightened with vertical bolts. It is.

Embodiments of the present invention will be described below with reference to FIGS. 1 and 2.

In the figure, 16 is a plurality of unit pump elements arranged in a column, 17 and 18 are a lower casing and a discharge casing arranged at the lower and upper ends of the unit pump element 1, 19 is a cylindrical body for tightening, and 20 is a cylindrical body for tightening. In the bearing casing, 21 is a check valve. Said cylindrical body 1
9 has a thread groove 22 inside its lower end, and is coupled to the lower casing 17 by screwing this thread groove 22 into a threaded portion formed on the outer periphery of the lower casing 17. A member 24 having a bolt 23 projecting vertically is fixed inside the upper part of the cylindrical body 19. The fixing means for this member 24 is that in the one shown in FIG. 1, the member 24 is formed into a ring shape;
The structure is such that a threaded portion formed on the outer periphery of the member is screwed into a threaded groove 25 formed inside the upper part of the cylindrical body 19 for fixation, and in the one shown in FIG. A locking body 26 such as a C-ring, for example, a member elastically protruding outward is provided on the upper outer edge of the cylindrical body 19. It is configured to be fixed by fitting into a concave groove 27 formed inside the. Note that the means for fixing this member 24 is not limited to the above-mentioned method, but may also be performed by means such as welding. The discharge casing 18 is located above the fixing member 24 and has holes 2 corresponding to the bolts 23 of the member 24.
8, and after passing the bolt 23 through the hole 28, the nut 29 is screwed in and tightened, thereby the discharge casing 18 is connected to the cylindrical body 19, and the lower casing 17 is connected to the lower casing 17 via the bearing casing 20. The unit pump element 16 is clamped using the same force.

Next, a procedure for assembling the slim submersible pump having the above structure will be explained.

First, a plurality of unit pumps 16 are stacked on the lower casing 17, and then the bearing casing 20 is stacked on top of the lower casing 17.

Next, the cylindrical body 19 is placed over the bearing casing 20, and the thread groove 22 inside the lower part of the cylindrical body 19 is screwed into the threaded portion on the outer periphery of the lower casing 17.
At this time, the screwing strength does not need to be strong, and it is sufficient to lightly screw it in by hand.

Next, the threaded portion on the outer periphery of the member 24 with the plurality of bolts 23 protruding from it is inserted into the threaded groove 25 on the inner periphery of the upper part of the cylindrical body 19.
and fix the member 24 to the cylindrical body 19.
The fixing position of this member 24 is determined so that a gap is created between the upper surface of the member 24 and the lower surface of the discharge casing 18 when the discharge casing 18, which will be described below, is tightened. The threading strength between the cylindrical body 19 and the member 24 does not need to be strong in this case as well, and may be sufficient to be screwed by hand to the above-mentioned fixed position.

Next, a check valve 21 is arranged in the upper part of the bearing casing 20, and the discharge casing 18 is further arranged in the member 24.
A plurality of bolts 23 protruding from the discharge casing 1
After passing through the same number of bolt holes 28 provided in 8, it is located on the member 24 and the bearing casing 20.

Next, the nut 29 is screwed onto the bolt 24 passed through the bolt hole 28 of the discharge casing 18, and the nut 29 is tightened to tighten the discharge casing 1.
8 and the lower casing 17 form a bearing casing 20.
The assembly is completed by tightening the plurality of unit pump elements 16 through the screws.

According to the above configuration, the cylindrical body 19 only needs to be screwed into the lower casing 17, and there is no need to screw it in strongly. That is, this threaded portion is connected to the cylindrical body 19.
There is a hook that prevents the pipe from moving in the axial direction, so it can be screwed together without the need for any pipe wrench. Therefore, assembly is easy, and there is no problem of denting of the cylinder body 19 by a pipe wrench. However, since the output can be increased, the number of stages of the unit pump elements 16 can be reduced.

In addition, since the nut 29 is screwed onto the bolt 23 and tightened, in other words, the discharge casing 18 is not rotated during tightening, so there is no possibility that the internal unit pump element 16 may rotate or a gap shift may occur. Its characteristics are stable, and it is easy to disassemble and assemble after long-term use.

In the above embodiment, the bolt 23 is attached to the member 2.
4 is a implanted structure, but the bolt is attached to member 24.
It is also possible to have a structure in which it is screwed into.

In addition, the discharge casing 18 and the bearing casing 2
0 may be configured integrally.

As explained above, according to the present invention, it is easy to disassemble and assemble, and stable pump characteristics can be obtained without unreasonable displacement of internal elements due to assembly, which is of great value. be.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional side view of a slim submersible pump according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of main parts of another embodiment of the present invention, and FIGS. 3 and 4 are of a conventional slim submersible pump. FIG. 16...Unit pump element, 17...Lower casing, 18...Discharge casing, 19...Cylindrical body, 22...Thread groove, 23...Bolt, 24...
Member, 28...hole, 29...nut.

Claims (1)

[Claims] 1. A lower casing and a discharge casing are arranged at the lower and upper parts of a plurality of unit pump elements arranged in series, and a tightening cylindrical body surrounding the unit pump elements is provided, and a tightening cylindrical body is provided inside the lower part of the cylindrical body. The threaded groove is screwed into the threaded part on the outer periphery of the lower casing, and the member fixed inside the upper part of the cylindrical body and the discharge casing arranged above are tightened with vertical bolts, and the lower casing and the discharge casing are connected to each other. A casing tightening device for a slim submersible pump, which tightens the unit pump element through a bearing casing on the unit pump element. 2. The casing tightening device for a slim submersible pump according to claim 1, wherein the bolt is implanted in a member fixed inside the upper part of the cylindrical body, and a hole through which the bolt is inserted is formed in the discharge casing. 3. Claim 1, characterized in that the fixing member is formed in a ring shape, and is fixed to the cylindrical body by screwing a threaded portion formed on the outer periphery into a threaded groove formed inside the upper part of the cylindrical body. A casing tightening device for a small submersible pump according to item 1 or 2. 4. The fixing member is formed in a ring shape, has a locking member that springs outward on the upper outer edge, and is fixed to the cylindrical body by fitting the locking member into a recess formed inside the upper part of the cylindrical body. A casing tightening device for a slim submersible pump according to claim 1.