CN115163516A - Water pump system for monitoring jacking amount - Google Patents

Abstract

The application relates to a water pump system of monitoring jack-up volume contains: a water pump and a sensor assembly. The water pump includes a thrust assembly and a rotor assembly. The thrust assembly comprises a thrust pad and a thrust bearing head, and the lower surface of the thrust bearing head is arranged on the upper surface of the thrust pad. The rotor assembly includes a pump shaft to which a thrust bearing head is fixedly connected axially and circumferentially. The sensor assembly is used to measure the axial displacement of the thrust bearing head relative to the thrust shoe.

Description

Water pump system for monitoring jacking quantity

Technical Field

The present application relates to a water pump system, and in particular to a water pump system capable of visually monitoring the amount of lift between a thrust shoe and a thrust bearing head before start-up and during the course of operation.

Background

In fields such as nuclear power plants, circulating water systems are commonly used to provide a required amount of cooling water to the condensers of the turbines and the heat exchangers of conventional island auxiliary cooling water systems during operation of the unit. The circulating water pump is an important component in a circulating water system, and the reliable operation of the circulating water pump is related to the stable operation of a nuclear power station and the like.

Large flow rate of circulating water pump from nuclear power plant (e.g. greater than 30 m) ³ /s seawater) the circulating water pump operates to generate a large downward axial thrust force applied to the rotor assembly. In some cases, the maximum thrust may be up to, for example, about 200 tons. To counter this axial thrust, circulating water pumpsA thrust assembly is provided. Typically, the thrust system has a high pressure oil supply assembly. Before starting the pump, a high-pressure oil supply assembly is used for enabling a thrust bush of a high-pressure oil thrust assembly to be located between a thrust head and a thrust pad so as to form an oil film between the thrust bush and the thrust pad, thereby preventing dry friction of a bearing bush when the pump is started, prolonging the service life of a thrust bearing and preventing bush burning. While an oil film is formed between the thrust pad and the thrust collar, the thrust collar is pushed away from the thrust pad by a certain slight axial distance, for example 0.05-0.25mm, by the high-pressure oil film. This axial distance is also referred to as the jack-up.

Whether the high-pressure oil supply assembly is started successfully is generally judged by the oil pressure indicated by a pressure gauge or a pressure sensor on the high-pressure oil supply assembly pipeline. For example, if the oil pressure reaches a certain threshold for a period of time, the high pressure oil supply assembly is deemed to be successfully activated. However, this monitoring method directly measures the pressure in the high-pressure oil line and does not intuitively reflect the distance that the thrust head is pushed away from the thrust shoe by the high-pressure oil film. For example, in the event of a blockage in the high pressure oil line downstream of a pressure gauge or pressure sensor, the read oil pressure may reach a threshold and last for a period of time. At this time, it may be erroneously judged that the high-pressure oil supply assembly is successfully started, and the high-pressure oil is not supplied between the thrust pad and the thrust collar, thereby causing wear or pad burning. Therefore, when installing the circulating water pump, a manual rack gauge is also typically required to measure the actual jack-up height.

It can be seen that there is a need in the art for a measurement procedure that intuitively reflects the distance that a thrust head is pushed away from a thrust shoe by a high pressure oil film in a circulating water pump.

Disclosure of Invention

One aspect of the present application relates to a water pump system including a water pump and a sensor assembly. The water pump includes a rotor assembly and a thrust assembly for jacking the rotor assembly. The thrust subassembly contains thrust tile and thrust bearing head, and the lower surface setting of thrust bearing head is on the upper surface of thrust tile. The rotor assembly includes a pump shaft to which a thrust bearing head is fixedly connected axially and circumferentially. The sensor assembly is used to measure the axial displacement of the thrust bearing head relative to the thrust shoe. The water pump system provided by the application can be used for intuitively measuring the axial displacement of the thrust bearing head relative to the thrust shoe, and whether the jacking is successful or not is presumed without the aid of pressure measurement of a high-pressure oil pipeline, so that the water pump system is more reliable in the starting and running processes.

In some embodiments, the thrust assembly further comprises a high pressure oil supply assembly. The high-pressure oil supply assembly is used for delivering high-pressure oil between the upper surface of the thrust pad and the lower surface of the thrust bearing head, so that an oil film is formed between the upper surface of the thrust pad and the lower surface of the thrust bearing head, and the thrust bearing head and the pump shaft move upwards relative to the thrust pad in an axial direction to enable the thrust bearing head to move axially relative to the thrust pad, namely, jacking quantity.

In some embodiments, the sensor assembly includes one or more sensors and one or more sensor brackets for fixedly mounting the respective sensors relative to the thrust shoe. Each of the one or more sensors is for measuring an axial displacement of the thrust bearing head relative to the thrust shoe.

In some embodiments, the thrust assembly further comprises a thrust bearing support for supporting portions of the thrust assembly, a thrust bearing cavity for receiving other portions of the thrust assembly, and a thrust bearing cover plate for covering the thrust bearing cavity. The thrust bearing cavity is fixedly attached to the thrust bearing support and houses at least a portion of the thrust pad, the thrust bearing head, and the pump shaft. The thrust pads are disposed within the thrust bearing cavity in a fixed manner relative to the thrust bearing mount, and the thrust bearing cover plate is fixedly attached to the thrust bearing cavity.

In some embodiments, one or more of the sensors is a non-contact displacement sensor, such as an eddy current displacement sensor, to accurately and non-contactingly sense a distance change using internal eddy currents generated by a metal conductor as it moves in an alternating magnetic field.

In some embodiments, the one or more sensor brackets are fixedly connected to the thrust bearing cover plate via fasteners, and each of the one or more sensors is fixedly connected to a respective one of the one or more sensor brackets such that the positions of the one or more sensors, the one or more sensor brackets, the thrust bearing cover plate, the thrust bearing cavity, and the thrust pads are fixed relative to each other. Therefore, although the sensor directly measures the axial displacement between the thrust bearing cover plate and the thrust bearing head, the displacement can intuitively reflect the axial displacement, i.e., the jacking amount, between the thrust shoe and the thrust bearing head.

In some embodiments, the one or more sensors include two sensors.

In some embodiments, the two sensors are arranged at 90 ° circumferentially relative to each other about the longitudinal axis of the water pump, thereby measuring the amount of lift at different orientations to provide more reliable results.

In some embodiments, the sensor assembly further comprises a monitoring device communicatively connected to the one or more sensors to convert, record and/or display the sensed signals received from the one or more sensors as a numerical value of the axial displacement of the thrust bearing head relative to the thrust shoe.

In some embodiments, the water pump system is used in a nuclear power circulating water system.

Drawings

Embodiments of the present application are further described, by way of example, with reference to the accompanying drawings, which form a part of this specification, and in which:

FIG. 1 is a schematic illustration of an example of a water pump system according to the present application;

FIG. 2 is a schematic cross-sectional view of a portion of a water pump system according to an embodiment of the present application;

FIG. 3 is a schematic diagram of sensors in a water pump system according to an embodiment of the present application;

FIG. 4 is a schematic top view of a plurality of sensor arrangements in a water pump system according to an embodiment of the present application;

fig. 5A-5C are side, front, and top views of a sensor mount in a water pump system according to an embodiment of the present application.

Detailed Description

Further features, advantages and effects of the present application will become apparent and more thorough apparent to those skilled in the art from the following detailed description of the embodiments, taken in conjunction with the accompanying drawings and detailed description. In the following description, spatial and orientational terms such as "upper", "lower", "front", "rear", "top", "bottom", "vertical" and "horizontal" may be used to describe embodiments of the invention, but it is understood that these terms are merely for convenience in describing the embodiments shown in the drawings and do not require that the actual device be constructed or operated in a particular orientation. In the following description, the use of terms such as "connected," "coupled," "secured," and "attached" may refer to two elements or structures being directly connected without other elements or structures therebetween, or indirectly connected through intervening elements or structures, unless expressly stated otherwise herein. In order to make the characteristics and advantages of the present application clearer, conventional arrangements known in the art in water pump systems may be omitted from the following description, which should not be construed as excluding these conventional arrangements from the water pump systems discussed in the present application.

Fig. 1 is a schematic diagram of an example of a water pump system 1 according to the present application. As shown in fig. 1, the water pump system 1 may include a motor 10 for providing rotation, a gear box 20 for reducing the rotation provided by the motor 10, an impeller 50 connected to the gear box 20 and outputting the rotation to a pump shaft 30 and mounted on the pump shaft 30 for transmitting the rotation to liquid, a thrust assembly 40 (shown as a dashed box) for providing an axially upward force to the pump shaft 30, and a flow passage 60 for inflow and outflow of fluid. The water pump system 1 according to the present application may include other parts and components known or yet to be developed in the art, such as auxiliary pipes, sealing members, couplings, etc., as will be appreciated and as needed by those skilled in the art upon reading the present application. These components are those required by the water pump to perform the function of pumping water flow, but are not necessarily linked to monitoring the amount of lift between the thrust shoes 412 and the thrust bearing heads 414. Accordingly, these components may be omitted from the following description of the specific embodiments. The particular implementation of these components may be selected by those skilled in the art according to the particular design requirements of the water pump system.

Referring to fig. 1, in some embodiments, a water pump system 1 may include a water pump and a sensor assembly, as shown in more detail below with reference to fig. 2-5C. Fig. 2 is a schematic cross-sectional view of a part (a dashed box in fig. 1) of the water pump system 1 according to an embodiment of the present application. In some embodiments, the water pump includes a rotor assembly and a thrust assembly for jacking the rotor assembly. In some embodiments, the thrust assembly includes a thrust shoe 412 and a thrust bearing head 414, a lower surface of the thrust bearing head 414 being disposed above an upper surface of the thrust shoe 412. In some embodiments, the rotor assembly includes the pump shaft 30, and the thrust bearing head 414 is fixedly connected axially and circumferentially to the pump shaft 30 such that the axial displacement and rotational movement of the two are synchronized. The sensor assembly may be used to measure the axial displacement of the thrust bearing head 414 relative to the thrust shoe 412. For example, before the water pump is started, the thrust bearing head 414 is jacked up a slight axial displacement, which is the "jacking amount" used in the context of this application, when high-pressure oil supplied by a high-pressure oil supply assembly 416, as will be described in more detail later, forms an oil film between the lower surface of the thrust bearing head 414 and the upper surface of the thrust shoe 412. At this point, a sensor assembly containing, for example, displacement sensor 510 may directly measure the axial displacement, thereby visually providing a value of the axial displacement to monitoring device 518 via cable 519 for recording and viewing, as will be described in greater detail below. Unlike conventional designs that rely on a pressure gauge or pressure sensor on the line 417 in the high pressure oil supply assembly 416 to infer jack-up, the water pump system 1 according to the present application can directly measure the amount of jack-up. Therefore, the phenomenon that the jack-up amount is measured by a manual frame meter can be avoided, and accidents such as tile burning and the like caused by misjudgment of the jack-up amount due to reasons such as oil circuit blockage are also avoided.

With further reference to fig. 2, in some embodiments, the thrust assembly 40 of the water pump system 1 according to the present application may further include a high pressure oil supply assembly 416 for delivering high pressure oil between the upper surface of the thrust shoe 412 and the lower surface of the thrust bearing head 414 via the conduit 416. The high pressure oil may form an oil film and cause the thrust bearing head 414, with the pump shaft 30 fixedly attached axially and circumferentially thereto, to move axially upward relative to the thrust shoe 412 by the lift amount described above. The high pressure oil supply system 416 may employ any technique known and yet to be developed in the art, such as with a high pressure oil pump, to supply high pressure oil to a designated location via a conduit 417, for example, between the upper surface of the thrust shoe 412 and the lower surface of the thrust bearing head 414. Lubrication by an oil film separates the thrust bearing head 414 from the thrust shoe 412 by a small distance to reduce friction and also acts as a heat transfer medium. It should be understood that, as used herein, the amount of jacking (or the relative axial displacement between the thrust shoe 412 and the thrust bearing head 414) refers to the difference between the distance after the oil film is formed between the thrust shoe 412 and the thrust bearing head 414 by the high pressure oil and the distance before the high pressure oil is injected (e.g., in a shutdown state), such as in the range of 0.05mm to 0.25mm. As an example, if the distance between the thrust shoe 412 and the thrust bearing head 414 before the high-pressure oil is injected is 0.02mm, and the distance between the upper surface of the thrust shoe 412 and the lower surface of the thrust bearing head 414 after the high-pressure oil is injected to form an oil film is 0.10mm, the lift-up amount in this case is 0.10mm to 0.02mm =0.08mm. It should be appreciated that in other embodiments, the amount of lift between the thrust shoe 412 and the thrust bearing head 414 may be within other numerical ranges, such as greater than 0.25mm or less than 0.05mm.

In some embodiments, high pressure oil line 417 of high pressure oil supply assembly 416 and thrust assembly 40 are threaded, high pressure oil supply assembly 416 is mounted to the side of thrust bearing bracket 410, and high pressure oil supply assembly 416 provides high pressure oil to the thrust assembly (particularly between thrust shoe 412 and thrust bearing head 414) through high pressure oil line 417.

With further reference to fig. 2, in some embodiments, a sensor assembly of a water pump system 1 according to the present application may include one or more sensors 510 for measuring the axial displacement, i.e., the amount of jacking, of the thrust bearing head 414 relative to the thrust shoe 412. The sensor assembly of water pump system 1 may also include one or more sensor brackets 514 for fixedly mounting the respective sensor 510 relative to thrust shoe 412. It should be understood that this is not meant to fix the sensor 510 or the sensor holder 514 directly to the thrust shoe 412, but rather to mean that substantially no relative axial movement occurs between the sensor holder 514 and the thrust shoe 412 for fixing the sensor 510. For example, as will be described in greater detail below, in some embodiments, thrust shoes 412, thrust bearing cavities 418, thrust bearing supports 410, and thrust bearing cover plate 419 may be fixed (i.e., do not produce relative movement) with respect to one another. In this case, fixedly mounting sensor 510 and sensor bracket 514 on any of thrust bearing cavity 418, thrust bearing bracket 410, and thrust bearing cover plate 419 may enable fixedly mounting sensor 510 relative to thrust shoe 412.

In some embodiments, thrust assembly 40 of water pump system 1 according to the present application may further include a thrust bearing support 410, a thrust bearing cavity 418, and a thrust bearing cover plate 419 for supporting portions of thrust assembly 40. A thrust bearing cavity 418 may be fixedly attached to thrust bearing support 410 and configured to receive thrust shoe 412, thrust bearing head 414, and a portion of pump shaft 30 between the upper and lower ends of thrust assembly 40. In some embodiments, thrust shoe 412 may be disposed within thrust bearing cavity 418 in a fixed manner relative to thrust bearing support 410. In some embodiments, a thrust bearing cover plate 419 may cover thrust bearing cavity 418 and be fixedly connected to thrust bearing cavity 418. In some embodiments, thrust bearing cover plate 419 may be sealed peripherally to thrust bearing cavity 418 and peripherally to the outer perimeter of rotating thrust bearing head 414.

In some embodiments, one or more of the sensors 510 is a non-contact sensor capable of accurately measuring a change in distance, i.e., relative displacement, between an upper surface of the thrust bearing cover plate 419, e.g., as a metallic conductor, and a sensor probe end face (e.g., probe 511 described below with reference to FIG. 3). In some embodiments, the non-contact sensor may be an eddy current displacement sensor. Because of the advantages of good long-term working reliability, wide measuring range, high sensitivity, high resolution and the like, the eddy current displacement sensor is widely used in the real-time monitoring and fault diagnosis of the state of large-scale rotating machinery.

Without being bound by any theory, when a metal conductor is placed in a changing magnetic field or does a motion of cutting magnetic lines of force in the magnetic field, induced current in a vortex shape, namely, an electric vortex, is generated in the conductor. In general, an eddy current displacement sensor measures a change in distance between its measuring head and the surface of a metal conductor according to the above-described principle.

In some embodiments, a high-frequency oscillation current is conducted to the measuring head coil in the eddy current displacement sensor to generate an alternating magnetic field in the measuring head coil. When the measured metal conductor is close to the magnetic field, the surface of the metal conductor generates induced current and simultaneously generates an alternating magnetic field with the direction opposite to the direction of the measuring head coil. Due to the action of the opposing alternating magnetic field, the amplitude and phase of the high-frequency oscillating current in the measuring head coil (characteristic impedance of the coil) are changed, reflecting the change in the distance of the measuring head coil from the surface of the metal conductor. In case other factors affecting the characteristic impedance of the coil are substantially constant within a certain range, the characteristic impedance of the coil is substantially a single-valued function of the distance between the measuring head and the metal conductor. Based on this, the change of the distance between the measuring head coil and the metal conductor can be deduced by deriving the change of the voltage or current output by the sensor as the change of the characteristic impedance of the coil.

Although the sensor assembly in a water pump system according to embodiments of the present application is described herein with reference to a non-contact sensor, such as an eddy current displacement sensor, other forms and principles of displacement or distance sensors may be employed.

With further reference to FIG. 2, in some embodiments, a sensor assembly according to the present application may also include a monitoring device 518, the monitoring device 518 communicatively connected to the one or more sensors 510 via a cable 519 to convert, record and/or display sensed signals received from the one or more sensors 510 as a numerical value, i.e., the amount of jacking, of the axial displacement of the thrust bearing head 414 relative to the thrust shoe 412. In some embodiments, the monitoring device 518 may include a transmitter and a recording/display device (not shown). The transmitter is communicatively coupled to the sensor 510 to process the distance/displacement signal received from the sensor 510 into a standardized electrical signal (such as a voltage signal or a current signal) that complies with a certain industry standard. A recording/display device is communicatively coupled to the transmitter to convert the normalized electrical signal received from the transmitter into a jack-up quantity value, and to record the jack-up quantity value (e.g., a time-varying graphical representation) and/or present the jack-up quantity value to a technician, e.g., on a display, in real time. In some embodiments, the recording/display device comprises a paperless recorder.

Fig. 3 is a schematic diagram of a sensor 510 in the water pump system 1 according to an embodiment of the present application. Sensor 510 may have a probe 511 for detecting a change in distance, i.e., displacement, of a surface (e.g., the upper surface of thrust bearing head 414) opposite thereto. In some embodiments, one or more sensor brackets 514 according to the present application may be fixedly coupled to thrust bearing cover plate 419 via fasteners, such as screws/threads 512. Each of the one or more sensors 510 may be fixedly connected to a respective one of the one or more sensor brackets 514 such that the positions of the one or more sensors 510, the one or more sensor brackets 514, the thrust bearing cover plate 419, the thrust bearing cavities 418, the thrust shoes 412 are fixed relative to one another. In this case, when sensor bracket 514 is fixedly attached to thrust bearing cover plate 419, sensor 510 may, for example, directly measure the distance between probe 511 of sensor 510 and thrust bearing head 414. This change in distance may directly reflect a change in distance between thrust bearing cover plate 419 and thrust bearing head 414. Since the positions of the thrust bearing cover plate 419, the thrust bearing cavity 418, and the thrust pad 412 are fixed relative to each other, the change in the measured distance may also directly reflect the change in the distance between the thrust bearing head 414 and the thrust pad 412 (i.e., the jacking amount), thereby accurately determining whether jacking is successful. It will be appreciated that the amount of lift may also be visually reflected when the sensor bracket 514 is fixedly attached to the outer surface of the thrust bearing cavity 418 or the thrust bearing bracket 410, among other structures. In some embodiments, the sensor 510 may also have an output port 513 to transmit a signal indicative of the jack-up amount to a monitoring device 518 via a cable 519.

Fig. 4 is a schematic top view of a plurality of sensor arrangements in a water pump system 1 according to an embodiment of the present application. In some embodiments, the one or more sensors 510 of the sensor assembly of the water pump system 1 include two sensors 510A, 510B that may be arranged at 90 ° circumferentially relative to each other about a longitudinal axis of the water pump (shown as the center of a circle in fig. 4) via respective two sensor brackets 514A, 514B, as shown in top view in fig. 4. Two sensors 510A, 510B arranged at 90 ° degrees can measure the amount of lift at positions in two orthogonal directions in a plane perpendicular to the longitudinal axis of the water pump to make the measurement more reliable. In some embodiments, the sensor brackets 514A, 514B may be secured to an upper surface of the thrust bearing cover plate 419 via fasteners (such as a screw/nut arrangement) in the holes 515A, 515B, respectively. In some embodiments, the sensors 510A, 510B may be fixedly mounted in the holes 516A, 516B of the sensor brackets 514A, 514B, respectively, via, for example, screws/nuts.

Fig. 5A-5C are side, front, and top views, respectively, of a sensor bracket 514 in a water pump system 1 according to an embodiment of the present application. As shown in fig. 5A-5C, the sensor bracket 514 may have a generally L-shape in side view, with holes 515 in the vertical portion for fasteners to pass through to fixedly attach to, for example, the upper surface of the thrust bearing cover plate 419, and holes 516 in the horizontally extending portion for fixedly mounting the sensor 510.

In some embodiments, the water pump system 1 according to the present application is for a nuclear power circulating water system to ensure reliable operation of nuclear power plant water circulation.

While the present application has been described with reference to the above embodiments, those skilled in the art will appreciate that various changes may be made without departing from the spirit and scope of the present application, as defined by the appended claims. While this specification contains many specifics of particular implementations, these should not be construed as limitations on the scope of what may be claimed, but rather as descriptions of features specific to particular embodiments. The scope of the application is defined by the appended claims and equivalents thereof, and is not limited to the embodiments described above.

Claims (11)

1. A water pump system, comprising:

a water pump, comprising:

a rotor assembly, comprising:

a pump shaft, and

a thrust assembly for jacking the rotor assembly, comprising:

the thrust bearing shoe is arranged on the upper portion of the frame,

a thrust bearing head fixedly connected axially and circumferentially to the pump shaft, and a lower surface of the thrust bearing head disposed above an upper surface of the thrust shoe; and

a sensor assembly for measuring axial displacement of the thrust bearing head relative to the thrust pad.

2. The water pump system of claim 1, wherein the thrust assembly further comprises a high pressure oil supply assembly for delivering high pressure oil between an upper surface of the thrust shoe and a lower surface of the thrust bearing head to axially move the thrust bearing head, along with the pump shaft, upward relative to the thrust shoe by axial displacement of the thrust bearing head relative to the thrust shoe.

3. The water pump system of claim 1, wherein the sensor assembly comprises:

one or more sensors, each of the one or more sensors for measuring an axial displacement of the thrust bearing head relative to the thrust shoe,

one or more sensor brackets, each of the one or more sensor brackets for fixedly mounting a respective said sensor relative to the thrust shoe.

4. The water pump system of claim 1, wherein the thrust assembly further comprises:

a thrust bearing support for supporting portions of the thrust assembly,

a thrust bearing cavity fixedly attached to said thrust bearing support and adapted to receive at least a portion of said thrust shoe, said thrust bearing head, and said pump shaft, wherein said thrust shoe is fixedly disposed within said thrust bearing cavity relative to said thrust bearing support, an

A thrust bearing cover plate covering the thrust bearing cavity and fixedly connected to the thrust bearing cavity.

5. The water pump system of claim 1, wherein the one or more sensors are non-contact displacement sensors.

6. The water pump system of claim 5, wherein the non-contact displacement sensor is an eddy current displacement sensor.

7. The water pump system of claim 3, wherein the one or more sensor brackets are fixedly connected to the thrust bearing cover plate via fasteners and each of the one or more sensors is fixedly connected to a respective one of the one or more sensor brackets, a measurement head of each of the one or more sensors being aligned with an upper surface of the thrust bearing head to measure a relative axial displacement between the measurement head and the upper surface of the thrust bearing head.

8. The water pump system of claim 7, wherein the one or more sensors comprise two sensors.

9. The water pump system of claim 8, wherein the two sensors are arranged at 90 ° circumferentially relative to each other about a longitudinal axis of the water pump.

10. The water pump system of claim 1, wherein the sensor assembly further comprises a monitoring device communicatively connected to the one or more sensors to convert, record, and/or display sensed signals received from the one or more sensors as a numerical value of axial displacement of the thrust bearing head relative to the thrust shoe.

11. The water pump system according to any one of claims 1 to 10, wherein the water pump system is used for a nuclear power circulating water system.

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