KR101736268B1 - Submersible pump having a bearing cooling device - Google Patents

Abstract

The present invention relates to a submersible pump used for draining or water feeding and, more specifically, to a submersible pump provided with an oil cooling path, an oil inlet, and an oil outlet in a bearing housing to be able to cool down a high temperature in a bearing of the submersible pump in a forced circulation way by providing a cooling oil. In addition, the submersible pump (a submersible motor pump for draining, a submersible axial-flow pump, a submersible mixed-flow pump, etc.) of the present invention is used in an oil cooling and a water cooling ways together, such that a cooling effect is remarkable. Moreover, by forcibly discharging a heat to the outside, a shaft seal device, the bearing, and a motor can have a longer life span and have less maintenance costs, thereby having an economic effect.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a submersible pump having a bearing cooling device,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an underwater pump installed in water and used for drainage or pumping water, and relates to an underwater pump having a bearing cooling device.

Hereinafter, the submersible pump is referred to as "a pump including submerged motor pump, submerged axial flow pump, submerged submerged pump and the like, which is used by immersing the motor in water. The technical idea described below can be applied regardless of the type of underwater pump.

Generally, submersible pumps are widely used in various fields such as collecting the whole in a fluid and using it as drainage or pumping water, or transferring a liquid material to another process. Such an underwater pump is adapted to suck and discharge the fluid while rotating the impeller of the pump part by the operation of the motor.

The underwater pump is composed of a motor unit, a bearing cooling unit and a shaft unit, and a pump unit. A water pumping unit is installed at the lower end of the bearing housing so that water pumped by the pump unit can not be introduced into the motor. Cable is installed.

When the underwater pump installed in the water is operated, the motor rotor of the motor rotates and the heat generated inside the motor is transferred to the outer motor casing, cooled by the fluid contacting the outer circumferential surface of the motor casing, The heat is self-cooled by the grease inside the bearing.

Due to the nature of submersible pumps, when installed in water and operating, the water, which is a cooling medium, comes close to the motor, so it has excellent cooling effect. However, in the case of the bearing, there is no path for discharging the heat of the grease, which is the cooling medium, to the outside, and the cooling efficiency is lowered. In continuous operation, the temperature formed in the pump main bearing is about 40 ~ 100 ℃, and this temperature varies greatly depending on the capacity of the pump. The higher the capacity, the higher the temperature is formed.

Therefore, there is a problem that the life of the product is shortened due to the temperature rise of the pump main bearing located at the inner center of the sealed and waterproofed interior of the underwater pump.

In particular, the underwater pump has become large in size (discharge port diameter: 1200 mm or more) in the past, and the demand amount is also increasing gradually in the past. In the case of the motor, (F or H class) technology has been developed. However, in the case of the present bearing, there is no technique developed specifically to withstand high temperatures. It is the maximum permissible temperature of a bearing for a submersible pump specified by Korean Industrial Standard (KS) (80 ° C), and when the defective products are analyzed, the cause of the motor failure is that the coil of the motor stator is burned due to the constraint of the rotor due to the overheating of the bearings.

1. Korean Registered Patent No. 10-1597736 (published Feb. 25, 2016) 2. Korean Registered Patent No. 10-1104091 (published on January 12, 2012)

SUMMARY OF THE INVENTION The present invention has been developed in order to overcome the above problems, and an underwater pump capable of improving the cooling efficiency of a bearing is proposed.

A submersible pump having a bearing cooling apparatus according to the present invention comprises a main shaft rotatably provided at the center of an underwater pump, a motor coupled to an upper portion of the main shaft, a motor for rotating the main shaft, A pump main bearing for fixing the main shaft, a pump main bearing, an upper portion coupled to the motor casing, a lower portion coupled to the pump discharge casing, a hollow center portion, and an oil cooling passageway and the oil cooling passageway A bearing housing including a bearing cooling fin provided between the oil cooling passages, an oil pump provided in a space on one side of the upper portion of the bearing housing for oil circulation forcibly, an oil pump provided under the bearing housing, An oil chamber enclosing the oil chamber, An oil suction pipe extending to a lower portion of the oil pump and sucking bearing cooling oil in the oil chamber, and an oil suction pipe connected to the oil pump and the oil cooling passage, An oil supply line extending from an upper portion of the oil pump and connected to the oil cooling passage, the oil lubricated from the oil supply pipe is passed through the oil cooling passage And an oil discharge pipe for discharging the oil to the oil chamber.

Further, the present invention is characterized by further comprising a strainer provided at an end of the oil suction pipe, for preventing inflow of foreign matter such as sludge.

The bearing housing may further include a bearing cooling casing coupled to the bearing housing at a position facing the oil cooling passage in the bearing housing.

The apparatus may further include a plurality of bearing auxiliary cooling fins provided at regular intervals on an outer circumferential surface of the bearing cooling casing.

Further, the present invention is characterized by further comprising a plurality of oil cooling fins provided at regular intervals in the oil chamber.

Further, the oil cooling passage and the bearing cooling fin are spiral-shaped.

The apparatus further includes a leakage detection sensor provided in a space on the other side of the upper portion of the bearing housing to prevent bearing cooling oil leaking from the bearing housing from penetrating into the motor.

It is also possible to detect in real time that the temperature of the pump main bearing rises above a preset temperature and to have a plurality of holes for the upper bearing cover to be fixedly coupled to the bearing housing by a plurality of upper bearing cover fastening bolts, And a bearing temperature detecting sensor provided at a lower end of at least one of the plurality of upper bearing cover fastening bolts.

Since the underwater pump having the bearing cooling device according to the present invention uses the water-cooling type water for releasing the heat generated in the pump main bearing through the forced circulation system and the oil-cooled type for forcedly circulating the lubricating oil for the shaft- Thereby maximizing the cooling effect of the bearing.

In addition, the water pump of the present invention has an economical effect of facilitating maintenance and maintenance of the facility, extending the service life of the shaft device, the bearing, and the motor by continuously discharging generated hot heat to the outside, .

1 is a cross-sectional view showing a submersible pump to which the present invention is applied;
Fig. 2 is a cross-sectional view of Fig. 1 in which the bearing cooling and shaft-
Figure 3 is an enlarged cross-sectional view of the bearing cooling and shaft-

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

Like reference numerals are used for like elements in describing each drawing. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

And / or < / RTI > includes any combination of a plurality of related listed items or any of a plurality of related listed items.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention.

The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

Hereinafter, the submersible pump is referred to as "a pump including submerged motor pump, submerged axial flow pump, submerged submerged pump and the like, which is used by immersing the motor in water. The technical idea described below can be applied regardless of the type of underwater pump. In addition, "pump main bearing" includes the same meaning as thrust bearing.

The submersible pump according to the present invention comprises a bearing cooling device. The bearing cooling system allows the bearing to be cooled by forced circulation of oil through the hot heat generated by the pump main bearing when the submersible pump is operated.

Hereinafter, a submersible pump having a bearing cooling apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a sectional view showing a submersible pump to which the present invention is applied, and FIG. 2 is a sectional view in which a bearing cooling device and a shaft end device are installed.

1 and 2, a submersible pump 1001 according to the present invention includes a motor unit 100, a bearing cooling and shaft cap unit 200, and a pump unit 300 in the same manner as the conventional submersible pump 1000 And a shaft seal device 270 is installed at the lower end of the bearing housing 220 so that the water to be pumped by the pump section 300 can not be introduced into the motor 120, An underwater cable 171 is installed.

The motor unit 100 includes a main shaft 110, a motor 120, a motor casing 130, a motor bracket 140, a motor bracket cover 150, an upper bearing (radial bearing) 160, a cable gland 170 And a pump discharge pipe 180.

The main shaft 110 is located at the inner center of the submerged pump 1001. The main shaft 110 is rotatably fixed to the motor 120, the upper bearing 160, and the pump main bearing (thrust bearing) 210 so as to be rotated by the operation of the motor 120.

The motor 120 includes a motor rotor 121 and a motor stator 122 and is fixedly coupled to the main shaft 110. The propeller (impeller) 310 at the end of the main shaft 110 rotated by the rotation of the motor rotor 121 rotates and sucks the fluid from the pump suction casing 320 so that the pump discharge casing 330 and the pump discharge pipe (180) to the designated place.

The motor casing 130 surrounds the motor 120 so that the motor 120 is not separated from the main shaft 110. The motor bracket 140 is coupled to the motor casing 130 at an upper portion of the main shaft 110 and is provided for fixing the motor 120 and the main shaft 110.

The motor bracket cover 150 can be fitted to the upper portion of the motor bracket 140 and coupled by bolts. The upper bearing 160 is coupled to the upper end of the main shaft 110 and the motor 120 is coupled to the lower portion of the upper bearing 160. The cable gland 170 is located at the upper end of one side of the motor bracket cover 150 and is formed to connect the underwater cable 171.

The bearing cooling and shaft seal unit 200 will be described in detail in the description of FIG. 3 below.

The pump unit 300 includes a propeller 310, a pump suction casing 320, and a pump discharge casing 330.

The propeller 310 is fixedly coupled to the lower end of the main shaft 110 and sucks fluid from the pump suction casing 320 by rotation of the main shaft 110 which is rotated by operation of the motor 120, And the pump discharge pipe 180 to the designated place.

The pump suction casing 320 is fixedly coupled to the lower portion of the underwater pump 1001 and sucks the fluid by the rotation of the propeller 310 and transfers the fluid to the pump discharge casing 330.

The pump discharge casing 330 is coupled to the lower portion of the bearing cooling and shaft cap 200 and has an inner center portion vertically passed therethrough and an outer circumferential surface communicating with the pump suction casing 320 in the axial direction And a plurality of guide vanes (not shown) are formed in the water channel so as to naturally induce the flow of water upward.

3 is an enlarged cross-sectional view of the bearing cooling and shaft end device of FIG. 2;

Referring to Figure 3, the bearing cooling and shaft seal assembly 200 of the present invention includes a pump main bearing (thrust bearing) 210, a bearing housing 220, an upper bearing cover 231, a lower bearing cover 232, A bearing cooling casing 240, an oil pump 250, an oil chamber 260, a shaft end device 270, and a leakage detection sensor 280.

The pump main bearing 210 is located at the center of the inner part of the underwater pump 1001 and at the bottom of the motor 120. The pump main bearing 210 is fixedly coupled to the main shaft 110 in the bearing housing 220, .

The bearing housing 220 has a hollow at a central portion through which the main shaft 110 passes, and the upper and lower portions of the central portion at which the pump main bearing 210 is to be assembled are protruded. The upper part of the bearing housing 220 is engaged with the motor casing 130, and the lower part is coupled with the pump discharge casing 330. The position of the bearing housing 220 in contact with the bearing 210 may be a hollow shape in which the inner space is empty. The oil cooling passage 221 is provided on the outer surface of the space in contact with the bearing 210 in a spiral shape. The oil cooling passages 221 adjacent to each other in the up and down direction on the spiral are spaced apart. Thus, the oil cooling passage 221 functions as the cooling fin 222, whereby the contact surface of the oil cooling passage 221 with respect to the heat on the bearing is maximized, and the cooling efficiency can be maximized.

Here, the oil cooling passage 221 and the bearing cooling fin 222 are not limited to a helical shape and can be deformed into different forms if necessary.

Two holes are formed on one side of the bearing housing 220 so as to be connected to the oil pump 250 through an oil supply pipe 252 and an oil discharge pipe 253. The bearing housing 220, Two holes are formed in the lower part of the space where the oil pump 250 is installed so that the oil suction pipe 251 and the oil discharge pipe 253 are connected to the oil pump 250.

The upper bearing cover 231 is fixedly coupled to the bearing housing 220 by a plurality of upper bearing cover fastening bolts 233 at the upper portion of the pump main bearing 210 and has a bearing housing 220, And has a plurality of holes to be engaged by bolts 233. A bearing temperature detection sensor 234 may be installed at the lower end of at least one of the plurality of upper bearing cover fastening bolts 233. [

The bearing temperature detection sensor 234 senses in real time that the bearing 210 rises above a predetermined temperature and detects a signal passing through the inside of the upper bearing cover fastening bolt 233 to transmit the sensed value of the temperature sensor 234 Line can be installed.

The lower bearing cover 232 is fixedly coupled to the bearing housing 220 by a plurality of lower bearing cover fastening bolts 235 at the lower portion of the pump main bearing 210 and is fixedly coupled to the lower bearing cover 232 and the oil chamber cover 263 (Not shown).

The bearing cooling casing 240 has a hollow interior and is coupled with the bearing housing 220 at a position opposite to the oil cooling passage 221. O-ring grooves for preventing oil leakage are formed on the inner surface to prevent leakage of the oil, so that the oil-repelling O-rings 241 and 242 can be respectively inserted. Two holes are formed upward and downward so that the oil supply pipe 252 and the oil discharge pipe 253 are passed to one side and connected to the oil pump 250. In addition, a plurality of bearing auxiliary cooling fins 243 having a wing shape in the axial direction may be attached at regular intervals along the outer peripheral surface of the bearing cooling casing 240.

The oil pump 250 is disposed in a space on one side of the upper portion of the bearing housing 220 and includes an oil (low oil) suction pipe 251, an oil (low oil) oil supply pipe 252, ), A strainer 254, and an oil leakage prevention device 255.

The oil pump 250 is operated by the bearing temperature sensor 234 when the bearing 210 rises above a predetermined temperature and the bearing cooling oil 261 in the oil chamber 260 is supplied to the oil suction pipe 251 And supplies oil to the oil cooling passage 221 through the oil refueling pipe 252 to cool the pump main bearing 210. The bearing cooling oil 261 whose temperature has been raised while cooling the pump main bearing 210 is again discharged to the oil chamber 260 via the oil discharge pipe 253. [

The oil suction pipe 251 passes through one of the holes under the oil pump 250 and is connected to the oil chamber 260 and pumps the bearing cooling oil 261 in the oil chamber 260. The pumped bearing cooling oil 261 is moved to the oil refueling pipe 252. At this time, in order to prevent the bearing cooling oil 261, which is sucked into the oil pump 250, from leaking and flowing into the motor 120, an oil leakage prevention An apparatus 255 may be provided.

The oil supply pipe 252 is connected to the oil cooling passage 221 through a hole in the lower side of the bearing housing 220 and a hole in the lower portion of the bearing cooling casing 240 and is connected to the bearing cooling oil 261 to the oil cooling passage 221 to cool the pump main bearing 210. [

The oil discharge pipe 253 is connected to the upper hole on one side of the oil cooling passage 221 and the remaining holes on the lower portion of the oil pump 250 and is connected to the bearing cooling oil 261 having the increased temperature while cooling the pump main bearing 210, And then discharged to the oil chamber 260 again. At this time, in order to prevent the bearing cooling oil 261 discharged to the oil chamber 260 from leaking and flowing into the motor 120, an oil leakage prevention (not shown) is provided on the upper surface of the oil chamber 260 to which the oil discharge pipe 253 is connected. An apparatus 255 may be provided.

The oil leakage preventing device 255 is installed in the through hole where the oil suction pipe 251 and the oil discharge pipe 253 pass through the bearing housing 200 on the upper surface of the oil chamber 260. The oil leakage preventing device 255 may be installed to prevent the motor 120 from failing when the bearing cooling oil 261 in the oil chamber 260 flows into the motor unit 100 through the through hole. have.

In addition, when the bearing cooling oil 261 in the oil chamber 260 is sucked into the oil suction pipe 251, foreign substances such as sludge contained in the bearing cooling oil 261 are prevented from flowing, The strainer 254 may be installed at the lower end of the oil suction pipe 251 for use.

The oil chamber 260 is located in the lower portion of the bearing housing 220 and the oil chamber 260 is provided with bearing cooling oil 261 therein and the high temperature bearing cooling oil 261 introduced through the oil discharge pipe 253 Is cooled by the flow of water pumped by the operation of the underwater pump 1001 because it is located inside the channel of the pump discharge casing 330 and is cooled by the oil cooling pin 262 provided in the oil chamber 260, Can be further maximized.

The mechanical shaft seal 270 is fixedly installed between the lower bearing cover 232 and the oil chamber cover 263 in the oil chamber 260 at the lower end of the bearing housing 220, And is hermetically installed to prevent the water pumped by the pump unit 300 from penetrating into the motor unit 100 while being installed through the bearing housing 220.

The leakage detection sensor 280 is installed in the other space above the bearing housing 220 and is installed to prevent the bearing cooling oil 261 leaking from the bearing housing 220 from penetrating into the motor unit 100 To prevent the motor from malfunctioning due to oil penetration.

100:
110: main shaft 120: motor
121: motor rotor 122: motor stator
130: motor casing 140: motor bracket
150: Motor bracket cover 160: Upper bearing (radial)
170: Cable Grand 171: Underwater cable
180: Pump discharge pipe (column pipe)
200: Bearing cooling and shaft seal
210: pump main bearing (thrust) 220: bearing housing
221: Oil cooling passage 222: Bearing cooling pin
231: upper bearing cover 232: lower bearing cover
233: Upper bearing cover fastening bolt 234: Bearing temperature sensor
235: Lower bearing cover fastening bolt 240: Bearing cooling casing
241: Oil-repelling O-ring (upper) 242: Oil-repelling O-ring (lower)
243: Bearing auxiliary cooling fin 250: Oil pump
251: Oil (low-temperature oil) suction pipe 252: Oil (low-temperature oil)
253: oil (high-temperature oil) discharge pipe 254: strainer
255: oil leakage prevention device 260: oil chamber
261: Bearing cooling oil 262: Oil cooling pin
263: Oil chamber cover 270: Sealing device (mechanical seal)
280: Leak detection sensor
300: pump section
310: propeller (impeller) 320: pump suction casing
330: pump discharge casing
1000: Conventional underwater pump
1001: Submerged pump of the present invention

Claims (8)

A main shaft rotatably provided at the center of an underwater pump;
A motor coupled to an upper portion of the main shaft for rotating the main shaft;
A pump main bearing coupled to a main shaft at a lower portion of the motor and fixing the main shaft;
The pump main bearing is enclosed, the upper portion is coupled to the motor casing, the lower portion is coupled to the pump discharge casing, and the hollow portion has a hollow at the center, and is provided in the inner space between the oil cooling passages and the oil cooling passages along the oil cooling passages A bearing housing including a bearing cooling fin;
An oil pump provided in a space on one side of the upper portion of the bearing housing for forcibly circulating oil;
An oil chamber provided at a lower portion of the bearing housing and containing oil therein;
A shaft closing device installed to be hermetically sealed inside the oil chamber so that fluid is not penetrated into the motor;
An oil suction pipe extending to a lower portion of the oil pump and sucking bearing cooling oil in the oil chamber;
An oil refueling pipe connected to the oil pump and the oil cooling passage for refueling the oil sucked from the oil suction pipe to the oil cooling passage;
An oil discharge pipe extending from an upper portion of the oil pump and connected to the oil cooling passage and discharging the oil lubed from the oil lubrication pipe to the oil chamber through the oil cooling passage; / RTI >
Characterized in that the oil cooling passage and the bearing cooling fin are helical and the oil cooling passages adjacent to each other in the upper and lower directions on the spiral are separated from each other,
Wherein the oil pump forcibly circulates the oil to suppress a temperature rise of the bearing. delete The method according to claim 1,
And a bearing cooling casing coupled to the bearing housing at a position opposite to the oil cooling passage. The method of claim 3,
Further comprising: a plurality of bearing auxiliary cooling fins provided at regular intervals on an outer circumferential surface of the bearing cooling casing. The method according to claim 1,
Further comprising: a plurality of oil cooling fins provided at regular intervals in the oil chamber. delete The method according to claim 1,
And a leakage detection sensor provided in a space on the other side of the upper portion of the bearing housing and installed to prevent bearing cooling oil leaking from the bearing housing from penetrating into the motor. An underwater pump. The method according to claim 1,
Further comprising a bearing temperature sensor for sensing in real time that the temperature of the pump main bearing rises above a predetermined temperature and operating the oil pump when the temperature of the pump main bearing is detected to be higher than a predetermined temperature,
Further comprising an upper bearing cover having a plurality of holes for fixedly engaging the bearing housing by a plurality of upper bearing cover fastening bolts,
Wherein the bearing temperature detecting sensor is installed at a lower end of at least one of the plurality of upper bearing cover fastening bolts.

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