JP7161965B2 - VERTICAL SHAFT PUMP AND WEAR DETECTION METHOD - Google Patents

Description

TECHNICAL FIELD The present invention relates to a vertical shaft pump installed in a drainage pump station or the like, and more particularly to a vertical shaft pump having a structure suitable for maintenance of submerged bearings or submerged bearing sleeves. The present invention also relates to a method for detecting the amount of wear of a submerged bearing or a submerged bearing sleeve of such a vertical shaft pump.

Vertical shaft pumps are generally widely used as pumps for flood control (river drainage) and public sewage systems. A vertical shaft pump has an impeller arranged in a suction water tank, and pumps up liquid (for example, water) in the suction water tank and transfers it to another place. Such vertical shaft pumps are operated with the submersible bearings and submersible bearing sleeves immersed in water, and these members gradually wear and corrode over time. Therefore, it is necessary to inspect the vertical shaft pump periodically to check the wear condition of the submerged bearing and the submerged bearing sleeve, and to repair or replace them as necessary.

Patent Document 1 discloses a vertical shaft pump with a submersible bearing located below the impeller. A worker accesses the underwater bearing from the pump suction port, removes the bearing unit consisting of the underwater bearing and the bearing holder from the bearing housing, disassembles the bearing unit, and measures the amount of wear of the underwater bearing. According to the vertical shaft pump configured in this manner, the state of wear of the consumable members such as the submersible bearings can be appropriately detected without pulling the vertical shaft pump out of the suction water tank, and the proper replacement timing of the consumable members can be grasped and replaced. be able to.

JP 2007-285253 A

However, the bearing unit including the underwater bearing and the bearing holder is heavy (usually 20 kg or more), and sometimes requires an auxiliary device such as a hydraulic trolley to remove the bearing unit. In addition, the bottom surface of the suction water tank is slippery, and the bottom surface is sometimes slanted, resulting in low work safety.

Accordingly, the present invention provides a vertical shaft pump having a structure that enables detection of the amount of wear of the submersible bearing and the submersible bearing sleeve without removing the submersible bearing. The present invention also provides a method for detecting the amount of wear of a submerged bearing and/or a submerged bearing sleeve of such a vertical shaft pump.

In one aspect, a rotating shaft, an impeller fixed to the rotating shaft, a pump casing housing the impeller, and a submersible bearing arranged below the impeller and rotatably supporting the rotating shaft a water bearing sleeve fixed to the rotating shaft and supported by the water bearing, the rotating shaft having a groove formed in an outer peripheral surface of the rotating shaft; A vertical shaft pump is provided extending axially of and located inside said submersible bearing sleeve.

In one aspect, the groove has a flat bottom surface.
In one aspect, a portion of the inner peripheral surface of the underwater bearing sleeve is parallel to the bottom surface of the groove.
In one aspect, the vertical shaft pump further includes a lid fitted into the groove, and a bottom surface of the lid when fitted into the groove is parallel to the bottom surface of the groove.
In one aspect, the grooves are a plurality of grooves spaced apart in the circumferential direction of the rotating shaft.
In one aspect, the vertical shaft pump further includes a bearing holder that holds the submerged bearing, and a magnetic material that is arranged outside the submerged bearing.

In one aspect, a mark indicating the position of the magnetic member is formed on the end surface of the bearing holder.
In one aspect, the vertical shaft pump further includes a bearing holder that holds the submerged bearing, and a housing that holds the bearing holder, and the bearing holder and the housing have a hole located outside the submerged bearing. and the hole opens at the outer surface of the housing.
In one aspect, a mark indicating the position of the hole is formed on the end surface of the bearing holder.

In one aspect, the method for detecting the amount of wear of the hydrostatic bearing sleeve of the vertical shaft pump includes measuring the thickness of the hydrostatic bearing sleeve with an ultrasonic thickness gauge placed in the groove. provided.

In one aspect, in the method for detecting the amount of wear of the submerged bearing of the vertical shaft pump, a current measurement value is obtained by measuring the magnetism of the magnetic material with a magnetometer placed in the groove. and determining the amount of wear of the underwater bearing based on the difference between the initial measurement of the magnetism and the current measurement.

In one aspect, the method of detecting the amount of wear of the submersible bearing of the vertical shaft pump, wherein while changing the rotation angle of the rotating shaft with respect to the magnetic material, the magnetic material is detected by a magnetic measuring device arranged in the groove. measuring the magnetism of the magnetic material multiple times to obtain a plurality of measurements; determining from the plurality of measurements an initial value of the magnetism of the magnetic material over the predetermined range of rotation angles; The magnetism of the magnetic material at the current rotation angle of the rotating shaft is measured by the magnetism measuring device placed in the groove to obtain the current measurement value, and the magnetism corresponding to the current rotation angle. A method is provided for determining the amount of wear of the underwater bearing based on the difference between the initial value and the current measurement.

In one aspect, the method for detecting the amount of wear of the submersible bearing of the vertical shaft pump includes measuring the magnetism of the magnetic material in the hole with a magnetism measuring device arranged in the groove, and measuring the current measurement A method is provided for obtaining a value and determining the amount of wear of the underwater bearing based on the difference between the initial measurement of the magnetism and the current measurement.

In one aspect, the method of detecting the amount of wear of the submerged bearing of the vertical shaft pump, wherein while changing the rotation angle of the rotating shaft with respect to the submerged bearing, a magnetic measuring device arranged in the groove is used to detect the amount of wear in the bore. measuring the magnetism of the magnetic material a plurality of times to obtain a plurality of measurements; determining from the plurality of measurements an initial value of the magnetism of the magnetic material over the predetermined range of rotation angles; The magnetism of the magnetic material at the current rotation angle of the rotating shaft with respect to the magnetic material in the groove is measured by the magnetometer placed in the groove to obtain a current measurement, and the current rotation A method is provided for determining the amount of wear of the underwater bearing based on the difference between the initial magnetic value corresponding to the angle and the current measurement.

According to the present invention, the thickness of the underwater bearing sleeve can be measured by inserting an ultrasonic thickness gauge into the groove formed in the rotating shaft. Similarly, a magnetometer can be inserted into the groove to measure the magnetism, which varies depending on the thickness of the hydrobearing. Therefore, the amount of wear of the underwater bearing sleeve and the underwater bearing can be detected without removing the underwater bearing sleeve from the rotary shaft and without removing the underwater bearing from the bearing holder. Workers can work safely and quickly complete the measurement work.

It is a schematic diagram which shows one Embodiment of a vertical shaft pump. 1 is a cross-sectional view showing one embodiment of a submersible bearing, a bearing holder, and a rotating shaft; FIG. FIG. 3 is a cross-sectional view taken along line AA of FIG. 2; FIG. 4 is a diagram showing how an ultrasonic thickness gauge is used to measure the thickness of the underwater bearing sleeve. FIG. 5(a) is a perspective view showing a lid for fixing the posture of the probe of the ultrasonic thickness gauge in the groove, and FIG. 5(b) is a lid fitted into the groove. It is a cross-sectional view showing a state in which the FIG. 6(a) is a cross-sectional view showing another embodiment of the underwater bearing sleeve, and FIG. 6(b) is a cross-sectional view showing a rotating shaft to which the underwater bearing sleeve shown in FIG. 6(a) is fixed. be. FIG. 4 is a cross-sectional view showing another embodiment of the underwater bearing, bearing holder, and rotating shaft; FIG. 8 is a cross-sectional view taken along line BB of FIG. 7; FIG. 4 is a cross-sectional view showing another embodiment of the underwater bearing, bearing holder, and rotating shaft; FIG. 10 is a cross-sectional view taken along line CC of FIG. 9; It is a figure which shows a mode that the magnetism of a magnetic material is being measured with the magnetometer. FIG. 4 is a cross-sectional view showing another embodiment of the underwater bearing, bearing holder, and rotating shaft; FIG. 13 is a cross-sectional view taken along line DD of FIG. 12; FIG. 4 shows end faces of the bearing holder, the underwater bearing sleeve, and the rotating shaft; 15(a) to 15(e) are diagrams in which the rotation angle of the rotating shaft with respect to the magnetic material changes little by little. Fig. 10 is a graph showing the initial value of the magnetism of the magnetic material over the range of rotation angles from 0 degrees to 90 degrees; FIG. 4 is a cross-sectional view showing another embodiment of the underwater bearing, bearing holder, and rotating shaft; FIG. 18 is a cross-sectional view taken along line EE of FIG. 17; FIG. 10 is a cross-sectional view showing a state in which the plug is removed from the hole and the magnetic material is inserted into the hole; FIG. 10 is a diagram showing a state in which a plurality of magnetic materials are respectively arranged in a plurality of holes;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram showing one embodiment of a vertical shaft pump. As shown in FIG. 1 , the vertical shaft pump 20 is a pump for pumping up liquid in the suction water tank 1 .

The vertical shaft pump 20 is installed on the pump installation floor 2 . The vertical shaft pump 20 includes a rotating shaft 32 extending in a vertical direction, an impeller 31 fixed to the rotating shaft 32, a pump casing 27 housing the impeller 31 therein, and a pump pipe connected to the upper end of the pump casing 27. 28 , a curved discharge pipe 30 connected to the upper end of the pumping pipe 28 , and a discharge pipe 34 connected to the end of the curved discharge pipe 30 on the discharge side. The rotating shaft 32 is connected to a driving source (an electric motor, a diesel engine, a gas turbine engine, etc.) (not shown).

The pump casing 27 is suspended inside the suction water tank 1 by a pumping pipe 28 . A pump casing 27 comprises a suction bellmouth 22 , an impeller casing 21 and a discharge bowl 24 . The upper end of the discharge bowl 24 is connected to the lower end of the lift pipe 28 . The upper end of impeller casing 21 is connected to the lower end of discharge bowl 24 . The suction bell mouth 22 has a suction port 22 a that opens downward, and the upper end of the suction bell mouth 22 is connected to the lower end of the impeller casing 21 . The suction port 22 a is formed at the lower end of the pump casing 27 . Impeller 31 is housed within impeller casing 21 and discharge bowl 24 .

The pumping pipe 28 extends downward through an opening 5 formed in the pump installation floor 2 forming the upper wall of the suction water tank 1 . A mounting flange 33 is fixed to the upper end of the pumping pipe 28 . The mounting flange 33 is fixed to the pump installation floor 2 by foundation bolts (not shown). The rotating shaft 32 extends vertically through the curved discharge pipe 30 and the pumping pipe 28 , and the lower end of the rotating shaft 32 is positioned inside the suction bellmouth 22 . The rotating shaft 32 is rotatably supported by the outer bearing 45 and the underwater bearing 41 .

The rotating shaft 32 protrudes upward from the discharge curved pipe 30 and extends. The outer bearing 45 is arranged outside the curved discharge pipe 30 and rotatably supports the portion of the rotary shaft 32 protruding from the curved discharge pipe 30 . A submersible bearing that supports the rotating shaft 32 may also be disposed within the lift pipe 28 . The outer bearing 45 is fixed to the upper portion of the discharge curved pipe 30 and supports the upper portion of the rotating shaft 32 . The underwater bearing 41 is arranged below the discharge bowl 24 and the impeller 31 and supports the lower portion of the rotating shaft 32 .

The underwater bearing 41 is held by a bearing holder 47 . A plurality of support members 43 are fixed to the inner peripheral surface of the suction bell mouth 22 . The underwater bearing 41 and bearing holder 47 are supported by these support members 43 . The underwater bearing 41 is close to the suction port 22a of the suction bell mouth 22, and the operator can access the underwater bearing 41 through the suction port 22a.

Disposed within discharge bowl 24 is inner bowl 25 , which is connected to discharge bowl 24 by a plurality of guide vanes 37 . A plurality of guide vanes 37 are arranged above the impeller 31 (discharge side). A liquid flow path is formed between the inner surface of the discharge bowl 24 and the outer surface of the inner bowl 25 . When the impeller 31 rotates, the liquid in the suction water tank 1 is sucked through the suction port 22 a of the pump casing 27 . As the impeller 31 rotates, the liquid is transferred to the discharge pipe 34 through the pump casing 27 , the pumping pipe 28 and the discharge curved pipe 30 .

FIG. 2 is a sectional view showing one embodiment of the underwater bearing 41, the bearing holder 47, and the rotating shaft 32, and FIG. 3 is a sectional view taken along line AA of FIG. A cylindrical underwater bearing sleeve 50 is fixed to the outer peripheral surface of the rotating shaft 32 . The underwater bearing sleeve 50 is rotatably supported by the underwater bearing 41 . That is, the underwater bearing sleeve 50 is positioned inside the underwater bearing 41 , and the outer peripheral surface of the underwater bearing sleeve 50 is supported by the inner peripheral surface of the underwater bearing 41 . The underwater bearing sleeve 50 is made of a metal such as cemented carbide or stainless steel, and the underwater bearing 41 is made of a nonmetallic material such as resin, rubber or ceramics. The outer peripheral surface of the underwater bearing 41 is held by a bearing holder 47 .

The bearing holder 47 includes a cylindrical base 47a to which the underwater bearing 41 is fixed, a cylindrical elastic member 47b that holds the cylindrical base 47a, and a bearing casing 47c that holds the elastic member 47b. The bearing casing 47 c is fixed to the housing 55 , and the housing 55 is fixed to the support member 43 . The cylindrical base 47a is made of metal such as stainless steel, and the elastic member 47b is made of elastic resin such as rubber.

The rotating shaft 32 has a groove 35 formed on its outer peripheral surface. The groove 35 extends in the axial direction of the rotating shaft 32 and is located inside the hydrobearing sleeve 50 . The bottom end of the groove 35 reaches the bottom end of the rotating shaft 32 . The groove 35 has a flat bottom surface 35a. The groove 35 has such a depth that an ultrasonic thickness measuring device and a magnetic measuring device, which will be described later, can be inserted. In this embodiment, the depth of the groove 35 is greater than the sum of the thickness of the hydrobearing sleeve 50 and the hydrobearing 41 . The length of the groove 35 is greater than the axial length of the underwater bearing 41 . Further, the length of groove 35 is less than the axial length of hydrobearing sleeve 50 .

FIG. 4 is a diagram showing how the thickness of the underwater bearing sleeve 50 is measured by the ultrasonic thickness gauge 60. As shown in FIG. A probe 61 of an ultrasonic thickness gage 60 is inserted into the groove 35 and positioned within the groove 35 facing the hydrobearing sleeve 50 (ie, facing outward). In this state, the thickness gauge 60 measures the thickness of the underwater bearing sleeve 50 . The ultrasonic thickness gauge 60 can measure the thickness of the underwater bearing sleeve 50 made of metal, which is a magnetic material. Such an ultrasonic thickness gauge 60 is commercially available.

The measured value of the thickness of the underwater bearing sleeve 50 is automatically or manually input to the wear monitoring device 70 and stored in the storage device 70 a of the wear monitoring device 70 . The wear amount monitoring device 70 comprises a computer having a storage device 70a for storing programs and data (thickness measurement values, etc.) and a processing device (CPU, etc.) 70b for executing calculations according to instructions included in the program. be. The wear monitor 70 determines the wear of the hydrobearing sleeve 50 from the difference between the initial thickness measurement and the current thickness of the hydrobearing sleeve 50 . Initial measurements of the thickness of the underwater bearing sleeve 0 are pre-stored in the storage device 70a.

An initial measurement of the thickness of the hydrobearing sleeve 50 is the thickness of the hydrobearing sleeve 50 when the hydrobearing sleeve 50 is not worn. The thickness of the hydrobearing sleeve 50 when the hydrobearing sleeve 50 is not worn is the thickness of the hydrobearing sleeve 50 when the hydrobearing sleeve 50 is not worn (that is, after a new hydrobearing sleeve 50 has been installed, and measured by the ultrasonic thickness gauge 60 (before the vertical shaft pump 20 is started). The wear monitoring device 70 generates an alarm signal when the difference (absolute value) between the initially measured value and the current measured value of the thickness of the hydrobearing sleeve 50 exceeds a predetermined threshold. good too.

According to this embodiment, the thickness of the underwater bearing sleeve 50 can be measured without removing the underwater bearing sleeve 50 from the rotating shaft 32 and without removing the underwater bearing 41 from the bearing holder 47 . Therefore, the worker can safely carry out the work, and can quickly complete the measurement work.

FIG. 5(a) is a perspective view showing a lid 73 for fixing the posture of the probe 61 of the ultrasonic thickness measuring device 60 within the groove 35, and FIG. 5(b) is a perspective view showing the lid 73. FIG. 4 is a cross-sectional view showing a state of being fitted in a groove 35; The width of the lid 73 is smaller than the width of the groove 35 and configured to fit into the groove 35 . The lid 73 is detachably attached to the rotating shaft 32 . A bottom surface 73a of the lid 73 is flat. The bottom surface 73 a of the lid 73 when fitted into the groove 35 is parallel to the bottom surface 35 a of the groove 35 . A gap is formed between the bottom surface 73a of the lid 73 and the bottom surface 35a of the groove 35, and the probe 61 of the ultrasonic thickness gauge 60 is arranged in this gap.

The probe 61 contacts both the bottom surface 73a of the lid 73 and the bottom surface 35a of the groove 35, thereby stabilizing the attitude of the probe 61. FIG. That is, the probe 61 faces the radial direction of the underwater bearing sleeve 50 and the ultrasonic thickness gauge 60 measures the thickness of the underwater bearing sleeve 50 along the radial direction. According to this embodiment, the posture of the probe 61 is stabilized, so the ultrasonic thickness measuring device 60 can measure the accurate thickness of the underwater bearing sleeve 50 .

FIG. 6(a) is a cross-sectional view showing another embodiment of the underwater bearing sleeve 50, and FIG. 6(b) shows the rotating shaft 32 to which the underwater bearing sleeve 50 shown in FIG. 6(a) is fixed. It is a cross-sectional view. The underwater bearing sleeve 50 has a protrusion 50 a for fixing the position of the probe 61 of the ultrasonic thickness gauge 60 within the groove 35 . A bottom surface 50 a - 1 of the protrusion 50 a forms part of the inner surface of the underwater bearing sleeve 50 . The bottom surface 50a-1 of the protrusion 50a is flat and parallel to the bottom surface 35a of the groove 35. As shown in FIG. A gap is formed between the bottom surface 50a-1 of the projection 50a and the bottom surface 35a of the groove 35, and the probe 61 of the ultrasonic thickness gauge 60 is arranged in this gap.

The probe 61 contacts both the bottom surface 50a-1 of the projection 50a and the bottom surface 35a of the groove 35, which are part of the inner surface of the underwater bearing sleeve 50, thereby stabilizing the posture of the probe 61. FIG. That is, the probe 61 faces the radial direction of the underwater bearing sleeve 50 and the ultrasonic thickness gauge 60 measures the thickness of the underwater bearing sleeve 50 along the radial direction. According to this embodiment, the posture of the probe 61 is stabilized, so the ultrasonic thickness measuring device 60 can measure the accurate thickness of the underwater bearing sleeve 50 .

FIG. 7 is a sectional view showing another embodiment of the underwater bearing 41, the bearing holder 47, and the rotating shaft 32, and FIG. 8 is a sectional view taken along line BB of FIG. Details of this embodiment that are not particularly described are the same as those of the embodiment described with reference to FIGS.

The rotary shaft 32 has a plurality of grooves 35 spaced apart in its circumferential direction. As shown in FIG. 8, in this embodiment, four grooves 35 are formed on the outer peripheral surface of the rotating shaft 32 at regular intervals. According to this embodiment, the ultrasonic thickness measuring device 60 can measure the thickness of the hydrostatic bearing sleeve 50 at a plurality of measurement points located at different positions in the circumferential direction of the hydrostatic bearing sleeve 50 . Therefore, the overall wear amount of the underwater bearing sleeve 50 can be determined more accurately. In particular, according to this embodiment, the uneven wear amount of the underwater bearing sleeve 50 can be detected.

9 is a cross-sectional view showing another embodiment of the underwater bearing 41, bearing holder 47, and rotary shaft 32, and FIG. 10 is a cross-sectional view taken along line CC of FIG. Details of this embodiment that are not particularly described are the same as those of the embodiment described with reference to FIGS.

In this embodiment, the magnetic material 80 is arranged outside the underwater bearing 41 . In one example, magnetic material 80 is a permanent magnet. A magnetic material 80 is embedded in the bearing holder 47 . More specifically, the bearing holder 47 is formed with a radially extending bore 82 and the magnetic material 80 is disposed within the bore 82 . The hole 82 penetrates the bearing casing 47c and the elastic member 47b and reaches the cylindrical base 47a that holds the underwater bearing 41. As shown in FIG. The bottom of the hole 82 is located within the cylindrical base 47a. Aperture 82 may extend through cylindrical base 47a.

A thread groove (not shown) is formed in the inner peripheral surface of the hole 82 , and a screw 85 as a plug is screwed into the hole 82 . The magnetic member 80 is pressed against the bottom of the hole 82 (or the outer peripheral surface of the underwater bearing 41) by a screw 85, thereby fixing the position of the magnetic member 80. As shown in FIG. The magnetic material 80 has a spherical shape, but may have other shapes.

FIG. 11 is a diagram showing how the magnetism of the magnetic material 80 is measured by the magnetometer 90. As shown in FIG. A probe 91 of a magnetic measuring device 90 is inserted into the groove 35 and placed in the groove 35 facing the water bearing 41 (that is, facing outward). In this state, the magnetometer 90 measures the magnetism of the magnetic material 80 . The underwater bearing 41 is positioned between the probe 91 and the magnetic material 80 . The underwater bearing 41 made of a non-magnetic material has the effect of preventing the magnetic transmission of the magnetic material 80 , so the strength of the magnetism reaching the magnetic measuring device 90 varies depending on the thickness of the underwater bearing 41 . That is, as the thickness of the underwater bearing 41 decreases, the strength of the magnetism reaching the magnetometer 90 increases. Therefore, the thickness of the underwater bearing 41 can be estimated from the strength of the magnetism measured by the magnetometer 90 . Such a magnetic measuring instrument 90 is commercially available.

The magnetic measurement value is automatically or manually input to the wear amount monitoring device 70 and stored in the storage device 70 a of the wear amount monitoring device 70 . Initial measurements of magnetism are pre-stored in storage device 70a. The wear monitor 70 determines the wear of the underwater bearing 41 based on the difference between the initial and current measurements of magnetism.

The initial measurement of the magnetism of the magnetic material 80 is the measurement of the magnetism of the magnetic material 80 when the hydrobearing 41 is not worn. That is, in a state where the submersible bearing 41 is not worn (that is, after a new submersible bearing 41 is installed and before the operation of the vertical shaft pump 20 is started), the magnetic material is measured by the magnetic measuring device 90 . 80 magnetism is measured. The wear monitoring device 70 may generate an alarm signal when the difference (absolute value) between the initial and current measurements of magnetism exceeds a predetermined threshold.

According to this embodiment, the wear amount of the underwater bearing 41 can be detected without removing the underwater bearing 41 from the bearing holder 47 . Therefore, the worker can safely carry out the work, and can quickly complete the measurement work.

Embodiments of the lid 73 described with reference to FIGS. 5(a) and 5(b) or the hydrostatic bearing sleeve 50 described with reference to FIGS. 6(a) and 6(b) are shown in FIGS. It can be applied to the embodiment shown in FIG.

12 is a sectional view showing another embodiment of the underwater bearing 41, the bearing holder 47, and the rotating shaft 32, and FIG. 13 is a sectional view taken along line DD of FIG. Details of this embodiment that are not specifically described are the same as those of the embodiment described with reference to FIGS.

The rotary shaft 32 has a plurality of grooves 35 spaced apart in its circumferential direction, and a plurality of magnetic members 80 are arranged outside the underwater bearing 41 . The number of grooves 35 is the same as the number of magnetic members 80 . In one embodiment, the number of grooves 35 may differ from the number of magnetic materials 80 . As shown in FIG. 13, in this embodiment, four grooves 35 are formed on the outer peripheral surface of the rotary shaft 32 at equal intervals, and four magnetic members 80 are arranged around the underwater bearing 41 at equal intervals. there is That is, the four grooves 35 are arranged at intervals of 90 degrees around the axis of rotation 32 , and likewise the four magnetic members 80 are arranged at intervals of 90 degrees around the axis of rotation 32 .

FIG. 14 is a diagram showing end surfaces of the bearing holder 47, the underwater bearing sleeve 50, and the rotary shaft 32. FIG. As shown in FIG. 14, a mark 95 indicating the position of the magnetic member 80 is formed on the end surface of the bearing holder 47, more specifically, on the end surface of the bearing casing 47c. The rotation angle of the rotating shaft 32 with respect to the magnetic material 80 corresponds to the rotation angle of the groove 35 with respect to the mark 95 .

The wear amount of the underwater bearing 41 can be detected as follows. First, when the submersible bearing 41 is not worn out (that is, after a new submersible bearing 41 is installed and before the vertical shaft pump 20 starts operating), the rotary shaft relative to the magnetic member 80 is The magnetism of the magnetic material 80 is measured multiple times by the magnetometer 90 placed in the groove 35 while changing the rotation angle of the groove 32 to obtain multiple measurements.

15(a) is a diagram showing a state in which the rotation angle of the rotating shaft 32 with respect to the magnetic material 80 is 0 degrees, and FIG. FIG. 15(c) is a diagram showing a state in which the rotation angle of the rotating shaft 32 with respect to the magnetic material 80 is 45 degrees, and FIG. 15(e) is a diagram showing a state in which the rotation angle of the rotating shaft 32 with respect to the magnetic material 80 is 90 degrees.

The magnetism of the magnetic material 80 is measured by the magnetometer 90 in a state where the rotation angle of the rotating shaft 32 with respect to the magnetic material 80 is 0 degrees. The rotation angle of the rotating shaft 32 with respect to the magnetic material 80 is slightly changed, and the magnetism of the magnetic material 80 is measured by the magnetometer 90 . By repeating the same operation, the magnetism of the magnetic material 80 is measured by the magnetometer 90 until the rotation angle of the rotating shaft 32 with respect to the magnetic material 80 reaches 90 degrees. A plurality of measured values obtained at different rotation angles are automatically or manually input to the wear amount monitoring device 70 and stored in the storage device 70 a of the wear amount monitoring device 70 .

The wear monitoring device 70 determines an initial value of the magnetism of the magnetic material 80 over a predetermined range of rotation angles from the plurality of measurements. FIG. 16 is a graph showing the initial value of the magnetism of the magnetic material 80 over a range of rotation angles from 0 degrees to 90 degrees. Magnetic initial values other than the plurality of measurements obtained by the magnetometer 90 are calculated by interpolation. The initial value of magnetism at each rotation angle within the range of 0 to 90 degrees is stored in the storage device 70a of the wear monitoring device 70. FIG.

After a certain amount of time has passed since the start of operation of the vertical shaft pump 20, the operation of the vertical shaft pump 20 is stopped for maintenance. During this maintenance, the magnetism of the magnetic material 80 at the current rotation angle of the rotating shaft 32 with respect to the magnetic material 80 is measured by the magnetometer 90 to obtain the current measured value. As shown in FIG. 16, the wear amount monitoring device 70 determines the wear amount of the underwater bearing 41 based on the difference between the initial magnetic value corresponding to the current rotation angle and the current measured value.

The stop position of the rotary shaft 32 when the operation of the vertical shaft pump 20 is stopped can change depending on the inertial rotation of the rotary shaft 32 . As a result, the distance between the groove 35 of the rotary shaft 32 and the magnetic material 80 during magnetic measurement can also change. According to this embodiment, when the rotation of the rotating shaft 32 stops, the angle of any one of the four grooves 35 with respect to the magnetic material 80 is within the range of 0 to 90 degrees. Therefore, the initial value of the magnetism at the rotational angle of the rotating shaft 32 with respect to the magnetic material 80 when the rotating shaft 32 stops can be obtained from the storage device 70 a of the wear monitoring device 70 . The wear amount monitoring device 70 accurately measures the wear amount of the underwater bearing 41 based on the difference between the initial value of magnetism stored in the storage device 70a and the current measured value of magnetism output from the magnetism measuring device 90. can decide.

In this embodiment, since the wear amount of the underwater bearing 41 is detected using the four grooves 35 and the four magnetic members 80, the wear amount of the entire underwater bearing 41 can be detected. In particular, according to this embodiment, the uneven wear amount of the underwater bearing 41 can be detected. However, the present invention is not limited to this embodiment. In one embodiment, only one groove 35 and one magnetic material 80 may be used to detect the amount of wear of the underwater bearing 41 . For example, the rotation angle range of the rotating shaft 32 with respect to the magnetic material 80 is in the range of -20 to +20 degrees, and the initial value of the magnetism of the magnetic material 80 over this rotation angle range may be calculated. If the rotational angle of the rotating shaft 32 with respect to the magnetic material 80 when the rotating shaft 32 stops is within the range of -20 to +20 degrees, the wear amount monitoring device 70 detects the magnetic initial value stored in the storage device 70a. value and the current measurement of the magnetism output from the magnetometer 90, the amount of wear of the underwater bearing 41 can be determined.

17 is a sectional view showing another embodiment of the underwater bearing 41, the bearing holder 47, and the rotating shaft 32, and FIG. 18 is a sectional view taken along line EE of FIG. Details of this embodiment that are not specifically described are the same as those of the embodiment described with reference to FIGS.

In this embodiment, the bearing holder 47 and housing 55 have holes 100 for placing the magnetic material 80 outside the underwater bearing 41 . The hole 100 is located outside the hydrostatic bearing 41 and extends radially of the bearing holder 47 . Aperture 100 opens on the outer surface of housing 55 . The magnetic material 80 is not positioned within the bore 100 when the vertical shaft pump 20 is in operation. The opening of hole 100 is closed by plug 101 to prevent liquid from entering hole 100 . The plug 101 is composed of screws. A thread groove (not shown) is formed in the inner peripheral surface of the hole 100, and the plug 101 is screwed into the thread groove. The hole 100 passes through the housing 55, the bearing casing 47c, and the elastic member 47b and reaches the cylindrical base 47a that holds the underwater bearing 41. As shown in FIG. The bottom of the hole 100 is located within the cylindrical base 47a. Aperture 100 may extend through cylindrical base 47a.

When detecting the wear amount of the underwater bearing 41, the plug 101 is removed from the hole 100 and the magnetic member 80 is inserted into the hole 100 as shown in FIG. Additionally, a screw 105 is screwed into the hole 100 to force the magnetic material 80 into the hole 100 . The magnetic member 80 is pressed against the bottom of the hole 100 (or the outer peripheral surface of the underwater bearing 41) by the screw 105, thereby fixing the position of the magnetic member 80. FIG.

According to this embodiment, the magnetic material 80 is not placed in the hole 100 when the vertical shaft pump 20 is in operation. Therefore, it is possible to prevent a decrease in magnetism due to corrosion of the magnetic material 80 or the like. As a result, the wear amount of the underwater bearing 41 can be detected more accurately.

The embodiments shown in FIGS. 17-19 can also be applied to the embodiments described with reference to FIGS. 12-16. FIG. 20 is a diagram showing a state in which a plurality of magnetic members 80 are arranged in a plurality of holes 100, respectively. The method of detecting the amount of wear of the underwater bearing 41 described with reference to FIGS. 12 to 16 can be similarly applied to the embodiment shown in FIG. That is, the method of detecting the amount of wear of the underwater bearing 41 is to measure the magnetism of the magnetic material 80 in the hole 100 with a magnetic measuring device 90 arranged in the groove 35 while changing the rotation angle of the rotating shaft 32 with respect to the underwater bearing 41 . a plurality of measurements are obtained, an initial value of the magnetism of the magnetic material 80 over a predetermined range of rotation angles is determined from the plurality of measurements, and the axis of rotation relative to the magnetic material 80 in the bore 100 is determined. The magnetism of the magnetic material 80 at the current rotation angle of 32 is measured by the magnetometer 90 placed in the groove 35 to obtain the current measurement and the magnetic initial value corresponding to the current rotation angle. and determining the amount of wear of the underwater bearing 41 based on the difference between the value and the current measurement. 12-16 are applied to the embodiment shown in FIG. 20, the plurality of marks 95 shown in FIG. 14 indicate the positions of the plurality of holes 100, respectively.

The above-described embodiments are described for the purpose of enabling a person having ordinary knowledge in the technical field to which the present invention belongs to implement the present invention. Various modifications of the above embodiments can be made by those skilled in the art, and the technical idea of the present invention can be applied to other embodiments. Accordingly, the present invention is not limited to the described embodiments, but is to be construed in its broadest scope in accordance with the technical spirit defined by the claims.

1 Suction water tank 2 Pump installation floor 5 Opening 20 Vertical shaft pump 21 Impeller casing 22 Suction bell mouth 22a Suction port 24 Discharge bowl 25 Inner bowl 27 Pump casing 28 Lifting pipe 30 Discharge bent pipe 31 Impeller 32 Rotating shaft 33 Mounting flange 34 Discharge pipe 35 Groove 35a Bottom surface 37 Guide vane 41 Underwater bearing 43 Support member 45 Outer bearing 47 Bearing holder 47a Cylindrical base 47b Elastic member 47c Bearing casing 50 Underwater bearing sleeve 50a Projection 50a-1 Bottom surface 55 Housing 60 Ultrasonic thickness gauge 61 Probe 70 Wear monitoring device 70a Storage device 70b Processing device 73 Lid 73a Bottom surface 80 Magnetic material 82 Hole 85 Screw 90 Magnetic measuring device 91 Probe 95 Mark 100 Hole 101 Plug 105 Screw

Claims (14)

a rotating shaft;
an impeller fixed to the rotating shaft;
a pump casing housing the impeller;
an underwater bearing disposed below the impeller and rotatably supporting the rotating shaft;
a hydrostatic bearing sleeve fixed to the rotating shaft and supported by the hydrostatic bearing;
The rotating shaft has a groove formed on the outer peripheral surface of the rotating shaft,
The vertical shaft pump, wherein the groove extends in the axial direction of the rotating shaft and is located inside the submersible bearing sleeve. 2. The vertical shaft pump of claim 1, wherein said groove has a flat bottom surface. 3. The vertical shaft pump according to claim 2, wherein a portion of the inner peripheral surface of said underwater bearing sleeve is parallel to the bottom surface of said groove. The vertical shaft pump further includes a lid fitted into the groove,
3. The vertical shaft pump according to claim 2, wherein the bottom surface of said lid when fitted into said groove is parallel to the bottom surface of said groove. The vertical shaft pump according to any one of claims 1 to 4, wherein the grooves are a plurality of grooves spaced apart in the circumferential direction of the rotating shaft. The vertical shaft pump according to any one of claims 1 to 5, further comprising a bearing holder that holds the submerged bearing, and a magnetic material arranged outside the submerged bearing. 7. The vertical shaft pump according to claim 6, wherein a mark indicating the position of said magnetic member is formed on the end face of said bearing holder. The vertical shaft pump further includes a bearing holder that holds the underwater bearing, and a housing that holds the bearing holder,
the bearing holder and the housing have holes located outside the hydrostatic bearing;
6. The vertical shaft pump according to any one of claims 1 to 5, wherein said hole is open on the outer surface of said housing. 9. The vertical shaft pump according to claim 8 , wherein a mark indicating the position of the hole is formed on the end surface of the bearing holder. A method for detecting the amount of wear of the submersible bearing sleeve of the vertical shaft pump according to any one of claims 1 to 9,
A method of measuring the thickness of the hydrobearing sleeve with an ultrasonic thickness gauge placed in the groove. A method for detecting the amount of wear of the submersible bearing of the vertical shaft pump according to claim 6,
measuring the magnetism of the magnetic material with a magnetometer placed in the groove to obtain a current measurement;
A method for determining the amount of wear of the hydrobearing based on the difference between the initial measurement of the magnetism and the current measurement. A method for detecting the amount of wear of the submersible bearing of the vertical shaft pump according to claim 7,
While changing the rotation angle of the rotating shaft with respect to the magnetic material, the magnetism of the magnetic material is measured a plurality of times by a magnetic measuring device arranged in the groove to obtain a plurality of measured values;
determining from the plurality of measurements an initial value of the magnetism of the magnetic material over the predetermined range of rotation angles;
measuring the magnetism of the magnetic material at the current rotation angle of the rotating shaft with respect to the magnetic material by the magnetometer disposed in the groove to obtain a current measurement;
A method for determining the amount of wear of the underwater bearing based on the difference between the initial magnetic value corresponding to the current rotation angle and the current measured value. A method for detecting the amount of wear of the submersible bearing of the vertical shaft pump according to claim 8,
measuring the magnetism of the magnetic material in the hole by a magnetometer placed in the groove to obtain a current measurement;
A method for determining the amount of wear of the hydrobearing based on the difference between the initial measurement of the magnetism and the current measurement. A method for detecting the amount of wear of the submersible bearing of the vertical shaft pump according to claim 9,
obtaining a plurality of measured values by measuring the magnetism of the magnetic material in the hole a plurality of times with a magnetic measuring device arranged in the groove while changing the rotation angle of the rotating shaft with respect to the underwater bearing;
determining from the plurality of measurements an initial value of the magnetism of the magnetic material over the predetermined range of rotation angles;
measuring the magnetism of the magnetic material at the current rotation angle of the rotating shaft with respect to the magnetic material in the hole by the magnetometer disposed in the groove to obtain a current measurement;
A method for determining the amount of wear of the underwater bearing based on the difference between the initial magnetic value corresponding to the current rotation angle and the current measured value.

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