JP2001090695A - Vertical shaft pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vertical shaft pump capable of lowering the cost for maintenance and lowering the vibration and the noise. SOLUTION: A suction casing 2, an impeller casing 3, a diffuser casing 4 and a discharge casing 5 are arranged upward so as to form a pump casing. This casing is to be embedded underground, and the impeller casing 3 has an impeller 10 inside thereof, and the diffuser casing 5 has a diffuser 11 inside thereof. An opening 5-1 of the discharge casing 5 is closed by an upper cover 7, and a shaft 12 of the impeller 19 is connected to a motor provided on the upper cover 7 while passing through the upper cover 7. In a vertical shaft pump with this structure, a diffuser vane 11-1 is separated from the diffuser casing 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vertical pump, and more particularly to a large vertical pump used as a water pump for flood prevention measures, the vertical pump having an outer periphery filled with concrete.

[0002]

2. Description of the Related Art FIG. 3 shows a conventional vertical pump.
As shown in the figure, the bottom 15 of the pump pit 15
-1, the suction casing 2 is installed, the impeller casing 3 is mounted on the suction casing 2, and the diffuser casing 4 is mounted on the impeller casing 3. Further, the discharge casing 5 is installed on the upper floor surface 15-2 of the pump pit 15 so as to be located above the diffuser casing 4, and the impeller 10 incorporated into the impeller casing 3 from the opening 5-1 of the discharge casing 5. Further, internal structures such as the diffuser 11 incorporated in the diffuser casing 4 can be inserted and pulled out. C in the figure is a concrete structure. Impeller 1
0 indicates several impeller vanes 10-1 and one boss 1
Each impeller vane 10-1 is provided with a stem (not shown) for attachment to the boss 10-2.

The impeller boss 10-2 is a submerged bearing 1
3 is connected to a shaft 12 supported by the upper cover 7.
The stuffing box 8 and a shaft sealing device 9 installed inside the stuffing box 8 are provided at the penetrating portion to prevent water leakage.

Accordingly, with the rotation of the shaft 12, the liquid in the pit 15 is sucked from the suction flow path 1 and discharged from the suction flow path 6.
Is discharged from the nozzle.

In such prior art, the diffuser vane 1
1-1 is integrally attached to the diffuser casing 4 and the impeller casing 3 is attached to the diffuser casing 4. Therefore, when performing maintenance and inspection of the impeller 10 and the diffuser 11, the diffuser casing 4 and the impeller casing 3 are attached to the diffuser 11. And it was necessary to pull out with the impeller 10. In this case, since the diffuser casing 4 and the impeller casing 3 are heavy articles of large weight, the cost required for their removal and replacement is large. Also, since the diffuser casing 4 and the impeller casing 3 need to be pulled out, they cannot be buried in concrete, which is a great disadvantage in reducing vibration and noise during operation of the pump.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to reduce the cost of maintenance and inspection by enabling the impeller and the diffuser to be pulled out of the pump pit without removing the diffuser casing and the impeller casing. It is another object of the present invention to provide a vertical axis pump that enables a diffuser casing and an impeller casing to be embedded in concrete, thereby reducing vibration and noise.

[0007]

According to the present invention, a pump casing is constructed by arranging a suction casing, an impeller casing, a diffuser casing, and a discharge casing upward in this order. It is buried underground, the impeller casing has a built-in impeller, the diffuser casing has a built-in diffuser, and the discharge casing has an opening for incorporating and removing the impeller, and the opening is In a longitudinal pump closed by the upper cover and the shaft of the impeller is penetrated through the upper cover and connected to the prime mover installed on the upper part thereof,
The diffuser vanes of the diffuser are separated from the diffuser casing.

Therefore, the impeller and the diffuser can be lifted from the pump pit without removing the diffuser casing and the impeller casing, and the cost of maintenance and inspection of the impeller and the diffuser can be reduced. Further, since the maintenance and inspection of the impeller can be performed without removing the diffuser casing and the impeller casing, the diffuser casing and the impeller casing can be embedded in the concrete, so that vibration and noise can be reduced.

According to the present invention, a reinforcing ring is attached to the outer periphery of the diffuser vane.

By providing the reinforcing ring in this way, the strength of the diffuser vane can be sufficiently secured.

Further, according to the present invention, the impeller vane of the impeller is a movable blade, and the inner surface of the impeller casing is formed to have a spherical surface below the stem center line of the impeller vane and a cylindrical surface at the top. It is.

Usually, in the movable vane axial flow pump, the inner surface of the impeller casing and the outer peripheral surface of the impeller vane are spherical, and the diameter of the horizontal cutting circle is maximized at the central surface of the stem of the vane. Even when separated from the casing, the impeller cannot be pulled out of the impeller impeller casing. However, in the present invention, the impeller casing can be pulled out without removing the impeller casing even for the movable blade axial flow pump by making the inner surface shape of the impeller casing a cylindrical surface above the center line of the vane stem.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 shows a case where the present invention is applied to a vertical-axis pump having movable blades, and the same parts as those in FIG.

The suction casing 2, the impeller casing 3, the diffuser casing 4 and the discharge casing 5 are provided, and the outer periphery of the suction casing 2 and the discharge casing and the inside of the cone portion 2-1 of the suction casing are filled with concrete. Similar to the conventional example, but according to the present invention, the outer peripheries of the impeller casing 3 and the diffuser casing 4 are also filled with concrete 17, 18. Thus, the casings 2, 3, 4, 5
Is hardened by concrete 17 and 18, sufficient strength can be obtained even with a relatively thin casing, and vibration and noise can be reduced. Further, a blade 2-2 is provided inside the suction casing 2, and connects an outer portion of the straightening and suction casing to a cone portion.

The impeller 10 includes an impeller boss 10-
2 and several impeller vanes 10-1, the impeller boss 10-2 is attached to the lower end of the shaft 12, and the impeller vane 10-1 is attached to the impeller boss 10-2 by a stem (not shown). The points are the same as in the conventional example. And impeller vane 10-
The first stem is engaged with a control mechanism (not shown) provided in the impeller boss 10-2, and the control mechanism controls the mounting angle of the impeller vane 10-1. In the impeller casing 3, a lower portion 3a is formed into a spherical surface from a stem center line AA of a surface engaging with the impeller vane 10-1, and an upper portion 3b is formed into a cylindrical surface. With this configuration, even if the impeller vane 10-1 is a movable wing, the impeller 10 can be easily pulled upward.

The diffuser 11 includes a plurality of diffuser vanes 11-1, a diffuser boss 11-2, and an upper flange 11-3. And upper flange part 1
It is attached to the lower flange portion 7-1 of the upper cover 7 by 1-3. The diffuser vane 11-1 is inserted with a slight gap s in the radial direction between the diffuser vane 11-1 and the diffuser casing 4 so that the diffuser 11 can be easily pulled upward.

An underwater bearing 13 for supporting the shaft 12 is provided inside the diffuser boss 11-2, and the diffuser vane 11-1 is connected to the diffuser boss 11-1.
Is attached to the outer surface of the conventional example.

Further, similarly to the conventional example, the upper cover 7
It comprises a lower flange portion 7-1 and an upper flange portion 7-2. The lower flange part 7-1 is a diffuser 11
The upper flange portion 7-2 is attached to the upper surface of the discharge casing 5 by a bolt 7-3.
And the opening 5-1 is closed. A stuffing box 8 is provided at a portion where the shaft 12 passes through the upper flange portion 7-2 of the upper cover 7,
Water leakage from a gap between the shaft 12 and the upper cover 7 is prevented by the shaft sealing device 9 provided inside.

The suction casing 2 is connected to the suction flow path 1, and the discharge casing 5 is connected to the discharge flow path 6.

In operation, when the prime mover is driven to rotate the shaft 12, the impeller 10 rotates and the liquid flowing into the suction casing 2 from the suction passage 1 is added with kinetic energy by the impeller 10, and the kinetic energy is diffused by the diffuser. At 11, the pressure energy is converted into pressure energy, discharged through the discharge casing 5, and discharged into the discharge channel 6.

In the case where the vertical pump is out of order or in case of regular maintenance, the bolt 7-3 is removed and the discharge casing 5 and the upper cover 7 are released. When the wire of the crane is hung on the upper cover 7 and pulled up, the impeller 10 and the diffuser 11 are pulled up from the pump pit 15 together with the upper cover 7. In this way, it can be pulled up to the ground for maintenance or repair.

After the maintenance or repair is completed, the impeller 10 and the diffuser 11 are lowered together with the upper cover 7 into the pump pit 15, and the upper cover 7 is discharged and fixed to the casing 5 with bolts 7-3.

FIG. 2 shows another embodiment, in which a reinforcing ring 11-4 is provided on the outer periphery of the diffuser vane 11-1.
And a slight gap s is provided in the radial direction between the reinforcing ring 11-4 and the diffuser casing 4. The other parts are the same as those in the embodiment of FIG. 1, and the same parts are denoted by the same reference numerals and description thereof will be omitted.

By providing the reinforcing ring 11-4, the diffuser vane 11-1 is simply separated from the diffuser casing 4 as in the embodiment of FIG.
Therefore, measures such as increasing the thickness of the diffuser vane 11-1 become unnecessary.

As described above, in the vertical pump according to the present invention, the diffuser 11 is connected to the diffuser casing 4.
, The impeller 10 and the diffuser 11 can be lifted from the pump pit without removing the heavy diffuser casing 4 and the impeller casing 3, thereby greatly reducing the cost of maintenance and inspection.

Since the diffuser casing 4 and the impeller casing 3 do not need to be removed, they can be buried in concrete, the strength of which can be shared with concrete, and the production cost of these casings can be reduced. You can save money. Furthermore, since vibration and noise during pump operation are absorbed by concrete, vibration and noise can be reduced.

When the impeller vane 10-1 is a movable blade, the impeller casing 3 has a cylindrical inner surface 3b above the center line of the impeller vane 10-1, so that the impeller 10 can be easily pulled out. Become like

[0028]

As described above, according to the present invention, a pump casing is constructed by arranging a suction casing, an impeller casing, a diffuser casing, and a discharge casing upward in this order, and the pump casing is located underground. It is buried, the impeller casing has an impeller, the diffuser casing has a built-in diffuser vane, and the discharge casing has an opening for incorporating and removing the impeller, and the opening is closed by the upper cover. The diffuser vane of the diffuser is separated from the diffuser casing in the longitudinal pump connected to the prime mover mounted on the upper part of the impeller through the upper cover, and the diffuser casing and the impeller shaft are configured. Will be able to raise the impeller and diffuser without removing the over the casing from the pump pit, it is possible to reduce the cost of the impeller and diffuser of maintenance and inspection. In addition, since the maintenance and inspection of the impeller and the diffuser can be performed without removing the diffuser casing and the impeller casing, the diffuser casing and the impeller casing can be embedded in the concrete, and vibration and noise can be reduced. become.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a vertical axis pump of the present invention.

FIG. 2 is a longitudinal sectional view of a vertical axis pump according to a second embodiment of the present invention.

FIG. 3 is a longitudinal sectional view of a conventional vertical axis pump.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Suction flow path 2 ... Suction casing 2-1 ... Cone part 2-2 ... Blade 3 ... Impeller casing 4 ... Diffuser casing 5 ... Discharge casing 5-1・ ・ ・ Opening 6 ・ ・ ・ Discharge channel 7 ・ ・ ・ Top cover 7-1 ・ ・ ・ Lower flange 7-2 ・ ・ ・ Upper flange 7-3 ・ ・ ・ Bolt 8 ・ ・ ・ Stuffing box 9 ... Shaft sealing device 10 ... Impeller 10-1 ... Impeller vane 10-2 ... Impeller boss 11 ... Diffuser 11-1 ... Diffuser vane 11-2 ... Diffuser boss 11 -3 ・ ・ ・ Top flange part 11-4 ・ ・ ・ Reinforcing ring 12 ・ ・ ・ Shaft 13 ・ ・ ・ Underwater bearing 14 ・ ・ ・ Shaft coupling 15 ・ ・ ・ Pump pit 15-1 ・ ・ ・ Bottom part 15-2 ・··Up Part floor surface 17, 18, 19 ... concrete

Continued on the front page (72) Inventor Kazuyuki Sato 11-1 Haneda Asahimachi, Ota-ku, Tokyo F-term in Ebara Corporation 3H034 AA01 BB01 BB08 BB16 CC03 DD07 DD12 DD28 EE06 EE17

Claims (3)

[Claims] 1. A pump casing comprising a suction casing, an impeller casing, a diffuser casing, and a discharge casing arranged upward in this order, and a pump casing is buried underground. The impeller casing has a built-in impeller, the diffuser casing has a built-in diffuser, the discharge casing has an opening for incorporating and removing the impeller, the opening is closed by the upper cover, and the impeller shaft is A vertical-axis pump penetrating through an upper cover and connected to a prime mover mounted on an upper part thereof, wherein the diffuser vane of the diffuser is separated from a diffuser casing. 2. The vertical axis pump according to claim 1, wherein a reinforcing ring is attached to an outer periphery of the diffuser vane. 3. The impeller vane of the impeller is a movable vane, wherein the inner surface of the impeller casing has a spherical surface below the stem center line of the impeller vane and a cylindrical surface at the top. 3. The vertical axis pump according to 1.