JPH07109988A - Full round flow type canned motor pump - Google Patents

Abstract

PURPOSE:To provide a full round flow type canned motor pump which can prevent entering of slurry in respect to a rotor chamber without a filter. CONSTITUTION:In a canned motor pump, a circular space 55 is formed an an outer periphery of a canned motor 22. One end of the motor is provided with a pump suction port and impellers 15, 16. Self liquid is suctioned from the other end into a rotor chamber R, and discharged from the side of the impellers. A sand collar 40 for removing slurry is installed on a shaft end on the opposite side to the impellers.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a full-circulation canned motor pump, and more particularly to a full-circled canned motor pump having an annular space around the outer circumference of the canned motor.

[0002]

2. Description of the Related Art An all-circumferential flow type pump in which an annular flow path is formed in the outer peripheral portion of a canned motor has been known. Such a full-circulation pump is a kind of canned motor pump,
The pump casing is composed of a suction side casing, a discharge side casing, and an outer cylinder provided between the suction side casing and the discharge side casing. And
A canned motor is arranged in the pump casing, and the rotor of the canned motor is rotatably supported by bearings.

In the canned motor of the all-circumferential flow pump, the handling liquid discharged from the impeller is circulated to lubricate the bearing and cool the motor with the handling liquid.

[0004]

As described above, in the all-circumferential flow pump, the liquid to be handled is circulated in order to lubricate the bearings of the canned motor and cool the motor itself.
When the handling liquid flows into the canned motor, it is necessary to remove foreign substances in the handling liquid. Therefore, in the conventional pump, it was necessary to install a filter on the inflow side of the handling liquid to the canned motor.

However, when a large amount of slurry (solid matter such as sand) is contained in the liquid to be handled, there is a problem that the filter is clogged, the circulating flow is blocked, and the bearing is damaged in a short period of time. .

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a full-circulation canned motor pump which can prevent slurry from entering the rotor chamber without providing a filter.

[0007]

In order to achieve the above-mentioned object, the present invention provides an annular space on the outer circumference of a canned motor, a pump suction port and an impeller are provided at one end of the canned motor, and self-liquid is supplied from the other end. In a full-circulation canned motor pump configured to be taken into the rotor chamber and discharged from the impeller side, a sand collar for removing slurry is attached to the shaft end on the side opposite to the impeller. .

[0008]

According to the present invention having the above-described structure, the slurry liquid discharged from the impeller enters the casing on the side opposite to the impeller through the annular flow passage on the outer peripheral portion of the motor. In the casing on the side opposite to the impeller, a forced vortex is formed by the sand collar, and the slurry liquid is centrifugally separated by the forced vortex. The slurry passes near the inner surface of the casing, and most of it is discharged from the discharge port to the outside of the pump. Part of the slurry is again blown into the forced vortex inside the casing on the side opposite to the impeller by the sand color. On the other hand, part of the clean water after centrifugation passes through the axial gap between the sand collar and the non-rotating member typified by the bearing bracket, is guided into the rotor chamber, and is eventually discharged from the back side of the impeller. Return to the road. Also, if the slurry liquid flows backward when the pump is stopped,
The effect of the taper portion of the sand collar prevents the slurry from directly entering the rotor chamber.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An all-circulation canned motor pump according to the present invention will be described below with reference to FIGS. FIG. 1 is a cross-sectional view showing an all-round flow type in-line pump, which is a type of all-round flow type canned motor pump of the present invention. The in-line pump according to the present embodiment includes a suction side casing 1, a discharge side casing 5, and an outer cylinder 9 that connects the suction side casing 1 and the discharge side casing 5. The suction-side casing 1, the outer cylinder 9, and the discharge-side casing 5 are each provided with a flange portion extending outwardly on the outer peripheral portion of the end portion on the opening side. Then, the suction side casing 1 and the outer cylinder 9 are integrally connected by the adjacent flange portions being sandwiched by flanges 20 and 20 made of cast iron or the like and tightened with bolts. Also,
Similarly, the discharge-side casing 5 and the outer cylinder 9 are such that adjacent flange portions are sandwiched by flanges 21 and 21 made of cast iron such as cast iron and tightened by bolts.
Connected together. The suction side casing 1, the discharge side casing 5 and the outer cylinder 9 constitute a pump casing made of stainless steel plate, and a canned motor 22 is arranged in the pump casing.

A suction nozzle 2 having a suction flange 3 is connected to the suction side casing 1. Further, the discharge side casing 5 also has a discharge nozzle 6 having a discharge flange 7.
Are connected.

On the other hand, the first side is provided inside the suction side casing 1.
An inner casing 10 and a second inner casing 11 are provided, and the return vane 10 is provided inside the first inner casing 10.
a is installed, and inside the second inner casing 11, a guide device 13 that constitutes a guide vane or a volute is installed. The guide device 13 has a spigot fitting portion, and the spigot fitting portion is fitted to the motor frame 23 of the canned motor 22. A seal member 14 is interposed in the gap between the first inner casing 10 and the suction side casing 1, and the suction side (low pressure side) is provided by the seal member 14.
The discharge side (high pressure side) is sealed. Liner rings 18, 18 are held at the inner ends of the first inner casing 10 and the second inner casing 11.

Impellers 15 and 16 are housed inside the first inner casing 10 and the second inner casing 11, respectively, and these impellers 15 and 16 are each a canned motor 22.
Is fixed to and supported by the main shaft 17 of the.

The motor frame 23 of the canned motor 22 has a substantially cylindrical frame outer case 24, and frame side plates 25, 2 provided at openings on both sides of the frame outer case 24.
6 and 6. A cable housing 50 is fixed to the outer frame 24 of the frame by welding, and a lead wire is pulled out from a coil in the outer frame 24 of the frame and connected to a power cable in the cable housing 50. Motor frame outer body 2
A stay 51 is fixed to 4 by welding. Further, by welding the drain pipe 52 and the like from the outer cylinder 9 side to the motor frame outer case 24 side, the cable housing 50 and the outer cylinder 9 are welded together, and the pipe 52 and the outer cylinder 9 are welded together. It is fixed to the outer cylinder 9.

A stator 27 and a rotor 28 are arranged in the motor frame 23. The rotor 28 is supported by the main shaft 17, and a cylindrical can 29 is fitted inside the stator 27. Also,
A bearing housing 31 holding a radial bearing 30 is provided on the frame side plate 25, and the radial bearing 30 rotatably supports a shaft sleeve 43 fitted to the main shaft 17. The bearing housing 31 has an opening 31 a communicating with the rotor chamber R.

A bearing housing 32 is detachably mounted on the frame side plate 26 via an O-ring 38 made of an elastic material. The bearing housing 32 is mounted on the radial bearing 3.
3 and the fixed side thrust metal 34 are respectively held, and the radial bearing 33 is adapted to rotatably support the shaft sleeve 35 fitted to the main shaft 17. On the other hand, spindle 1
A thrust disk 36 is fixed to the discharge side end portion of No. 7, and the thrust disk 36 is provided with a rotating thrust metal 37 facing the fixed thrust metal 34.

A sand collar 40 for removing slurry is fixed to the shaft end of the main shaft 17 on the side opposite to the impeller. As shown in FIG. 2 (FIG. 2A is a sectional view and FIG. 2B is a side view), the axial gap δ ₁ between the sand collar 40 and the non-rotating member represented by the bearing housing 32 is It is set to less than 2 mm. Further, the radial gap δ ₂ between the sand collar 40 and the non-rotating member represented by the motor frame side plate 26 is set to less than ₂ mm.

As shown in FIG. 2, the sand collar 40 has a tapered surface 40a, and a wing shape 40b is provided by forming a recess from the tapered surface 40a. That is, the tapered surface 40a allows the annular space 55
The main flow of the pump flowing from the to the axis is smoothly guided in the axial direction. The blade shape 40b forms a forced vortex in the fluid to centrifuge the slurry liquid.

The operation of the in-line pump will be briefly described. The slurry liquid sucked from the suction nozzle 2 is
It is guided into the impeller 15 through the inner casing 10. The slurry liquid discharged from the rotating impeller 15 is formed between the outer cylinder 9 and the motor frame outer shell 24 of the canned motor 22 after the flow direction is changed from the radial direction to the axial direction through the guide device 13. And flows into the discharge-side casing 5 through the flow path 55.

In the discharge casing 5, the sand collar 4
A forced vortex is formed by 0, and the slurry liquid is centrifuged by this forced vortex. The slurry passes near the inner surface of the discharge side casing 5, and most of the slurry is discharged from the discharge port to the outside of the pump. Some slurries are sand color 4
By 0, it is again skipped into the forced vortex in the discharge side casing 5. On the other hand, part of the clean water after centrifugation passes through the back surface of the sand collar 40 and is guided into the rotor chamber R, passes through the opening 31a at the suction side end of the motor frame 23, and eventually the blades. It merges with the discharge flow of the car 15. Further, when the slurry liquid flows back when the pump is stopped, the slurry is prevented from directly entering the rotor chamber R by the effect of the taper of the taper portion 40a of the sand collar 40. In addition,
The foreign substance passable diameter of the passage 31a that connects the rotor chamber R and the pump chamber provided on the back surface of the impeller 16 is larger than the foreign substance passable diameter formed by the sand collar 40 and its corresponding bearing housing 32. It is set large.

FIG. 3 is a sectional view showing another embodiment of the full-circulation canned motor pump of the present invention. The full-circulation canned motor pump of this embodiment is an end-top type pump. The points different from the embodiments shown in FIGS. 1 and 2 are the number of impellers and the flow path configuration. That is, in this embodiment, only the single-stage impeller 15 is fixed to the main shaft 17. A cover 70 is fixed to the pump casing outer cylinder 9 by flanges 21 and 21.

A discharge nozzle 65 is fixed to the outer casing 9 of the pump casing by welding.
The discharge flange 66 is fixed to. Sand color 6
0 and the flow passage structure in the rotor chamber R are substantially the same as those in the embodiment shown in FIGS. However, since the sand collar 60 does not need to guide the main flow of the pump, it does not have a tapered surface and is not provided with a blade shape. In this embodiment, the fluid discharged from the impeller 15 is guided to the annular flow passage 55 and then discharged from the discharge nozzle 65. On the other hand, the annular flow path 5
A part of the fluid flowing in 5 flows into the space 71 between the cover 70 and the motor 22, flows into the rotor chamber R from the gap between the sand collar 60 and the bearing housing 32, and passes through the opening 31 a of the bearing bracket 31. Join the discharge stream. The operation of the sand collar 60 is similar to that of the embodiment shown in FIG.

[0022]

As described above, according to the present invention,
Since the sand collar for generating the forced vortex is provided in the discharge side casing, the slurry liquid can be forcibly separated and the slurry can be prevented from entering the rotor chamber. Further, since the slurry liquid can be continuously separated, it is not necessary to install a filter, and there is no fear that the filter will be clogged.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a full-circulation canned motor pump according to the present invention.

FIG. 2 is a diagram showing a main part of a canned motor pump according to the present invention, FIG. 2 (a) is a sectional view thereof, and FIG.
(B) is the side view.

FIG. 3 is a cross-sectional view showing another embodiment of the full-circulation canned motor pump according to the present invention.

[Explanation of symbols]

 1 Suction Side Casing 2 Suction Nozzle 5 Discharge Side Casing 6 Discharge Nozzle 9 Outer Cylinder 10, 11 Inner Casing 13 Guide Device 14 Sealing Member 15, 16 Impeller 17 Spindle 22 Canned Motor 23 Motor Frame 24 Motor Frame Outer Body 25, 26 Frame Side plate 27 Stator 28 Rotor 32 Bearing housing 40, 60 Sand collar 50 Cable housing

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Keita Uei 4-2-1 Honfujisawa, Fujisawa City, Kanagawa Prefecture EBARA Research Institute

Claims (6)

[Claims] 1. An annular space is provided on the outer circumference of a canned motor, a pump suction port and an impeller are provided at one end of the canned motor, and self-liquid is taken into the rotor chamber from the other end and discharged from the impeller side. An all-circumferential-type canned motor pump, wherein a sand collar for removing slurry is attached to the shaft end on the side opposite to the impeller. 2. The all-circumferential-flow canned motor pump according to claim 1, wherein an axial gap between the sand collar and a non-rotating member represented by a bearing housing is less than 2 mm. 3. The radial gap between the sand collar and a non-rotating member represented by a motor frame side plate is 2 mm.
The total flow canned motor pump according to claim 1 or 2, wherein 4. The full-circulation canned motor pump according to claim 1, wherein the sand collar is provided with a blade shape. 5. The sand collar is provided with a taper so that the main pump flow flowing from the annular space toward the axial center can be smoothly guided in the axial direction. Full-circulation canned motor pump described in. 6. A foreign matter passable diameter of a passage communicating with the rotor chamber and the pump chamber provided on the back surface of the impeller is larger than a foreign matter passable diameter formed by the sand collar and its counterpart. The full-circulation canned motor pump according to any one of claims 1 to 5, characterized in that there is.