Axial Flow Pump Rotor Ground Current Simulation Detection Device and Simulation Detection Method

Abstract

The present invention discloses an axial-flow pump rotor ground current simulation detection device and a simulation detection method. Among them, the simulation detection device includes a rotating component, a force measuring component and a supporting component; the rotating component includes a driving plate, a rotating plate, and a fixing plate connecting the driving plate and the rotating plate; the force measuring component includes a positioning mandrel, a connecting member, a weighing sensor and a lead screw; the supporting component includes a positioning plate, a positioning ring, and a support rod connecting the positioning plate and the positioning ring; the rotating plate is sleeved outside the positioning mandrel and can rotate around the positioning mandrel; the connecting member includes a connecting cross plate and a connecting vertical rod; one end of the lead screw passes through the positioning plate and is fixedly connected to the connecting cross plate; the weighing sensor is threadedly connected to the connecting vertical rod; the positioning mandrel is fixedly connected to the connecting vertical rod through an insulating plate; the lead screw is threadedly connected to the positioning plate. This device can simulate the axial force generated by the designed axial-flow pump during operation and detect the ground current of the axial-flow pump rotor under this axial force.

Description

Technical Field

[0001] The invention relates to the technical field of axial flow pumps, and in particular to a device and method for simulating detection of ground current of an axial flow pump rotor. Background Art

[0002] An axial flow pump is a pump that transports liquid along the axis by the force exerted by the blades of the rotating impeller on the liquid. There are several types: vertical, horizontal, oblique and cross-flow. When the axial flow pump is running, its rotor will generate a constant potential difference to the ground; an axial force (which can be calculated based on hydraulic parameters to obtain a relatively accurate value) and a radial force (the axial force component is large, and the radial force component is small) will be generated on the impeller (assembled together with the rotor), causing the rolling element of the rotor's supporting bearing to deviate from the center of the raceway and approach the raceway on one side. When the axial force reaches a certain value, the contact resistance between the rotor and the bearing and the bearing seat is very small, and the current flowing through the rotor, the inner ring of the bearing, the rolling element, the outer ring of the bearing, and the bearing seat will be very large, causing electrical corrosion between the rolling element and the raceway, forming washboard patterns on the raceway, causing the bearing to fail quickly, and ultimately causing the axial flow pump to fail.

[0003] Judging from the electrical corrosion failure phenomenon that occurs during the operation of many axial flow pumps at home and abroad, it is of great significance to the safe and reliable operation of axial flow pumps to understand the actual ground current of the rotor during operation and try to eliminate the probability of bearing electrical corrosion. However, there is currently no effective means to detect the ground voltage of the rotor of the axial flow pump, the contact resistance between the rotor, bearing, and bearing seat, and the ground current of the rotor during operation. Therefore, when designing axial flow pumps, manufacturers can only rely on theoretical calculations to roughly determine the bearing life of the designed axial flow pump. Summary of the invention

[0004] The purpose of the present invention is to provide an axial flow pump rotor to ground current simulation detection device to overcome the above-mentioned problems existing in the prior art. The axial flow pump rotor to ground current simulation detection device of the present invention can simulate the axial force generated by the designed axial flow pump during operation, and detect the ground current of the axial flow pump rotor under the axial force, so as to specifically eliminate the probability of electrical corrosion of the axial flow pump bearing and ensure the reliability of the operation of the designed axial flow pump. Correspondingly, the present invention also provides an axial flow pump rotor to ground current simulation detection method.

[0005] For the analog detection device, the technical solution of the present invention is: an axial flow pump rotor ground current analog detection device, comprising a rotating component, a force measuring component, and a supporting component; the rotating component includes a driving plate, a rotating plate, and a fixing plate disposed between the driving plate and the rotating plate; the force measuring component includes a positioning mandrel, a connecting member, a weighing sensor, and a lead screw; the supporting component includes a positioning plate, a positioning ring, and a supporting rod disposed between the positioning plate and the positioning ring; the driving plate is used to connect with the rotating shaft of the axial flow pump rotor, and the rotating plate is sleeved outside the positioning mandrel and can rotate around the positioning mandrel; the connecting member includes a connecting cross plate and a connecting vertical rod; one end of the lead screw passes through the positioning plate and is fixedly connected to the connecting cross plate; the weighing sensor is threadedly connected to the connecting vertical rod; the positioning mandrel is fixedly connected to the connecting vertical rod through an insulating plate; the lead screw is threadedly connected to the positioning plate; the positioning ring is used to be fixedly installed with the flange surface of the axial flow pump.

[0006] Compared with the prior art, the axial flow pump rotor ground current analog detection device of the present invention can simulate the axial force generated during the operation of the designed axial flow pump by setting the force measuring component and the rotating component, and then measure the DC resistance between the axial flow pump rotor and the bearing, bearing seat, and oil pump grounding seat under this axial force, as well as the ground voltage of the axial flow pump rotor, and calculate the ground current of the rotor, so as to determine the possibility of the axial flow pump occurring electric corrosion, and thus can specifically eliminate the probability of the axial flow pump bearing electric corrosion (such as taking insulation and other measures) to ensure the reliability of the operation of the designed axial flow pump.

[0007] As an optimization, in the axial flow pump rotor ground current analog detection device described above, a plain bearing is embedded in the rotating plate, and the positioning mandrel is inserted into the plain bearing. The plain bearing is used to bear the axial force generated during the test of the analog detection device, so as to avoid damage to the rotating plate due to long-term stress; in addition, the plain bearing is convenient for use and maintenance and is easy to replace.

[0008] As an optimization, in the axial flow pump rotor ground current analog detection device described above, the lead screw is fixedly connected to the connecting cross plate through a lead screw shaft head holding plate; the end of the lead screw is fixed in the lead screw shaft head holding plate, and the lead screw shaft head holding plate is threadedly connected to the connecting cross plate. Thus, it is convenient to make the force measuring component generate an axial displacement.

[0009] As an optimization, in the axial flow pump rotor ground current analog detection device described above, the number of the insulating plates is two, and both the connecting vertical rod and the positioning mandrel are fixed between the two insulating plates. Thus, the connection firmness between the connecting vertical rod and the positioning mandrel and the insulating plates can be ensured.

[0010] Furthermore, the connecting vertical rod and the positioning mandrel are threadedly connected to the two insulating plates. At this time, the structure is simple, easy to assemble, and has high connection firmness.

[0011] Furthermore, the insulating board is an epoxy glass cloth board. The epoxy glass cloth board has the characteristics of high mechanical and dielectric properties, good heat resistance and good moisture resistance. Using the epoxy glass cloth board as the insulating board can extend its service life while ensuring the insulation performance.

[0012] Furthermore, a retaining rod is provided on the connecting longitudinal rod. One end of the retaining rod is lapped on the support rod, and the other end passes through the insulating board and the connecting longitudinal rod and is locked and fixed by a nut. The design of the retaining rod is to restrict the connecting longitudinal rod so that it can only move axially and cannot move circumferentially, thus ensuring the stability of the entire simulation detection device during operation.

[0013] As an optimization, in the aforementioned axial flow pump rotor ground current simulation detection device, three support rods are provided between the positioning ring and the positioning plate. The two ends of the support rod are respectively connected to the positioning ring and the positioning plate by welding. Thus, a triangular connection structure can be formed between the positioning ring and the positioning plate, with good stability. Moreover, the positioning ring, the positioning plate and the support rod are connected by welding, which is convenient for processing and makes the entire support component have high firmness, large rigidity and good integrity, and can withstand greater pressure, thus ensuring the stability of the entire simulation detection device during operation.

[0014] As an optimization, in the aforementioned axial flow pump rotor ground current simulation detection device, two symmetrically distributed fixing plates are provided between the driving plate and the rotating plate. The two ends of the fixing plate are respectively connected to the driving plate and the rotating plate by threaded connections. Thus, the connection firmness between the driving plate and the rotating plate is ensured, and the disassembly and assembly are convenient.

[0015] For the simulation detection method, the technical solution of the present invention is: an axial flow pump rotor ground current simulation detection method, which is realized by using the aforementioned axial flow pump rotor ground current simulation detection device. First, remove the front housing and impeller of the axial flow pump. Pass the rotating shaft of the axial flow pump rotor through the positioning ring and fix it on the driving plate, and then install the positioning ring on the flange surface of the axial flow pump. During detection, rotate the screw rod clockwise to make the screw rod move upward, and drive the force measuring component to move upward to tension the rotating shaft, the rotating component and the force measuring component. The weighing sensor detects the actual tension value. When the measured tension value reaches the set value, stop rotating the screw rod. At this time, measure the DC resistance R between the rotor and the bearing, the bearing seat and the oil pump grounding seat. Then start the axial flow pump, the rotating shaft rotates, and drives the rotating component to rotate. Measure the ground voltage of the rotor at the positioning mandrel, and calculate the ground current value I of the axial flow pump rotor according to the formula I = U / R.

[0016] Compared with the prior art, the method for simulating and detecting the ground current of the axial flow pump rotor of the present invention can measure the ground current of the rotor of the axial flow pump during operation, so as to eliminate the probability of bearing electrical corrosion and ensure the reliability of the designed axial flow pump operation. This method first simulates the axial force generated by the designed axial flow pump during operation, measures the DC resistance between the rotor of the axial flow pump and the bearing, the bearing housing, and the oil pump grounding seat under this axial force, then measures the ground voltage of the rotor when the axial flow pump starts, and calculates the ground current of the rotor according to the formula I = U / R. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic structural diagram of the device for simulating and detecting the ground current of the axial flow pump rotor in an embodiment of the present application;

[0018] Figure 2 is Figure 1 the front view of the device for simulating and detecting the ground current of the axial flow pump rotor in

[0019] The reference signs in the drawings are: 1 - driving plate; 2 - fixing plate; 3 - rotating plate; 4 - positioning mandrel; 5 - insulating plate; 6 - connecting member, 601 - connecting cross plate, 602 - connecting longitudinal rod; 7 - weighing sensor; 8 - lead screw; 9 - positioning plate; 10 - support rod; 11 - positioning ring; 12 - bearing; 13 - retaining rod; 14 - lead screw shaft head clamping plate; 15 - screw; 16 - rotating shaft. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] The present application will be further described below with reference to the drawings and embodiments, but it shall not be used as a basis for limiting the present application.

[0021] See Figure 1 and Figure 2, the axial flow pump rotor ground current simulation detection device of the present invention includes a rotating component, a force measuring component, and a supporting component; the rotating component includes a driving plate 1, a rotating plate 3, and a fixing plate 2 disposed between the driving plate 1 and the rotating plate 3; the force measuring component includes a positioning mandrel 4, a connecting vertical rod 6, a weighing sensor 7, and a lead screw 8; the supporting component includes a positioning plate 9 (the positioning plate 9 is disc-shaped), a positioning ring 11, and a supporting rod 10 disposed between the positioning plate 9 and the positioning ring 11; the driving plate 1 is used to connect with the rotating shaft 16 of the axial flow pump rotor, and the rotating plate 3 is sleeved outside the positioning mandrel 4 and can rotate around the positioning mandrel 4 (the end of the positioning mandrel 4 passes through the rotating plate 3 and is fixedly connected with the insulating plate 5, and its head abuts against the rotating plate 3 to form a limit); the connecting member 6 includes a connecting horizontal plate 601 and a connecting vertical rod 602; one end of the lead screw 8 passes through the positioning plate 9 and is fixedly connected with the connecting horizontal plate 601; the weighing sensor 7 is threadedly connected with the connecting vertical rod 602; the positioning mandrel 4 is fixedly connected with the connecting vertical rod 602 through the insulating plate 5 (the insulating plate 5 is provided to play an insulating role and ensure the accuracy of subsequent tests); the lead screw 8 is threadedly connected with the positioning plate 9; the positioning ring 11 is used to be fixedly installed with the flange surface of the axial flow pump.

[0022] Embodiment:

[0023] In this embodiment, a plain bearing 12 is embedded in the rotating plate 3, and the positioning mandrel 4 is inserted into the plain bearing 12. The plain bearing 12 is used to bear the axial force generated during the test of the simulation detection device, so as to avoid damage to the rotating plate 3 due to long-term force; in addition, the plain bearing 12 is convenient for use and maintenance and is easy to replace.

[0024] In this embodiment, the lead screw 8 is fixedly connected with the connecting horizontal plate 601 through a lead screw shaft head holding plate 14; the end of the lead screw 8 is fixed inside the lead screw shaft head holding plate 14, and the lead screw shaft head holding plate 14 is bolted to the connecting horizontal plate 601. Thus, it is convenient to make the force measuring component generate an axial displacement.

[0025] In this embodiment, the number of the insulating plates 5 is two, and both the connecting longitudinal rod 6 and the positioning core shaft 4 are fixed between the two insulating plates 5. After clamping and fixing the connecting longitudinal rod 6 and the positioning core shaft 4 by the two insulating plates 5, the connection firmness between the connecting longitudinal rod 6 and the positioning core shaft 4 and the insulating plates 5 can be ensured. Further, the connecting longitudinal rod 6 and the positioning core shaft 4 are threadedly connected to the two insulating plates 5. At this time, the structure is simple, easy to assemble, and has high connection firmness. Further, the insulating plate 5 is an epoxy glass cloth board. The epoxy glass cloth board has the characteristics of high mechanical and dielectric properties, good heat resistance, and good moisture resistance; using the epoxy glass cloth board as the insulating plate 5 can extend its service life while ensuring the insulation performance. Further, a retaining rod 13 is provided on the connecting longitudinal rod 6; one end of the retaining rod 13 is lapped on the support rod 10, and the other end passes through the insulating plate 5 and the connecting longitudinal rod 6 and is locked and fixed by a nut. The design of the retaining rod 13 is to limit the connecting longitudinal rod 6 so that it can only move axially and cannot move circumferentially, thereby ensuring the stability of the entire simulation detection device during operation. During assembly, the two insulating plates 5 are respectively located on both sides of the connecting longitudinal rod 6, and the retaining rod 13 is sequentially passed through the first insulating plate, the connecting longitudinal rod 6, and the second insulating plate; then, on the retaining rod 6, outside the two insulating plates 5, a nut is respectively installed, and finally the nut is screwed and tightened to clamp the connecting longitudinal rod 6 by the two insulating plates 5 to complete the fixation. The positioning core shaft 4 is fixedly connected to the two insulating plates 5 by a screw 15. During assembly, the two insulating plates 5 are respectively located on both sides of the positioning core shaft 4, and the screw 15 is sequentially passed through the first insulating plate, the positioning core shaft 4, and the second insulating plate; then, on the screw 15, outside the two insulating plates 5, a nut is respectively installed, and finally the nut is screwed and tightened to clamp the positioning core shaft 4 by the two insulating plates 5 to complete the fixation.

[0026] In this embodiment, three support rods 10 are provided between the positioning ring 11 and the positioning plate 9; both ends of the support rods 10 are respectively connected to the positioning ring 11 and the positioning plate 9 by welding. Thus, a triangular connection structure can be formed between the positioning ring 11 and the positioning plate 9, with better stability. Moreover, the positioning ring 11 and the positioning plate 9 are connected to the support rods 10 by welding, which is convenient for processing and makes the entire support component have higher firmness, greater rigidity, and better integrity, and can withstand greater pressure, thereby ensuring the stability of the entire simulation detection device during operation.

[0027] In this embodiment, two symmetrically distributed fixing plates 2 are provided between the driving plate 1 and the rotary plate 3; both ends of the fixing plates 2 are respectively connected to the driving plate 1 and the rotary plate 3 by bolts. Thus, the connection firmness between the driving plate 1 and the rotary plate 3 is ensured, and the disassembly and assembly are convenient.

[0028] Detection method of the axial flow pump rotor ground current simulation detection device of the present invention. First, remove the front housing and impeller of the axial flow pump; pass the rotating shaft 16 of the axial flow pump rotor through the positioning ring 11 and fix it on the driving plate 1 (the rotating shaft 16 and the driving plate 1 are connected by a flat key), and then install the positioning ring 11 on the flange surface of the axial flow pump. During detection, rotate the lead screw 8 clockwise to move the lead screw 8 upward and drive the force measuring components (the positioning mandrel 4, the insulating plate 5, the connecting piece 6, and the load cell 7) upward to tension the rotating shaft 16, the rotating component, and the force measuring components (the rotary plate 3 is tensioned with the positioning mandrel 4, and the driving plate 1 is tensioned with the rotating shaft 16); the load cell 7 detects the actual tension value. When the measured tension value reaches the set value (the set value is set according to the axial force of the designed axial flow pump), stop rotating the lead screw 8. At this time, measure the DC resistance R between the rotor and the bearing, the bearing seat, and the oil pump grounding seat; then start the axial flow pump, the rotating shaft 16 rotates and drives the rotating component to rotate (the rotary plate 3 rotates around the positioning mandrel 4), and the force measuring components do not move. Measure the ground voltage U of the axial flow pump rotor at the positioning mandrel 4, and calculate the ground current value I of the axial flow pump rotor according to the formula I = U / R. Thus, by adjusting the insulation between the axial flow pump rotor and the bearing seat, the ground current value of the axial flow pump rotor can be restricted, the occurrence of electrocorrosion can be eliminated, and the reliability of the axial flow pump operation can be ensured.

[0029] The above general description of the invention involved in this application and the description of its specific implementation manners should not be understood as a limitation on the technical solution of the invention. Those skilled in the art can, based on the disclosure of this application, without violating the constituent elements of the involved invention, add, subtract, or combine the disclosed technical features in the above general description or / and specific implementation manners (including embodiments) to form other technical solutions within the protection scope of this application.

Claims

1. Axial flow pump rotor ground current simulation detection method, Characterized in that: This method is realized by using an axial flow pump rotor ground current simulation detection device; the axial flow pump rotor ground current simulation detection device includes a rotating component, a force measuring component and a supporting component; the rotating component includes a driving plate (1), a rotating plate (3), and a fixing plate (2) arranged between the driving plate (1) and the rotating plate (3); the force measuring component includes a positioning mandrel (4), a connecting piece (6), a weighing sensor (7) and a lead screw (8); the supporting component includes a positioning plate (9), a positioning ring (11), and a supporting rod (10) arranged between the positioning plate (9) and the positioning ring (11); the driving plate (1) is used to connect with the rotating shaft (16) of the axial flow pump rotor, and the rotating plate (3) is sleeved outside the positioning mandrel (4) and can rotate around the positioning mandrel (4); the connecting piece (6) includes a connecting cross plate (601) and a connecting vertical rod (602); one end of the lead screw (8) passes through the positioning plate (9) and is fixedly connected with the connecting cross plate (601); the weighing sensor (7) is threadedly connected with the connecting vertical rod (602); the positioning mandrel (4) is fixedly connected with the connecting vertical rod (602) through an insulating plate (5); the lead screw (8) is screwed with the positioning plate (9); the positioning ring (11) is used for installing and fixing with the flange surface of the axial flow pump; First, remove the front housing and impeller of the axial flow pump, pass the rotating shaft (16) of the axial flow pump rotor through the positioning ring (11) and fix it on the driving plate (1), and then install the positioning ring (11) on the flange surface of the axial flow pump; during detection, rotate the lead screw (8) clockwise to move the lead screw (8) upward and drive the force measuring component to move upward, so that the rotating shaft (16), the rotating component and the force measuring component are tensioned; the weighing sensor (7) detects the actual tension value, and when the measured tension value reaches the set value, stop rotating the lead screw (8). At this time, measure the DC resistance R between the rotor and the bearing, bearing seat, and oil pump grounding seat; then start the axial flow pump, the rotating shaft (16) rotates and drives the rotating component to rotate, measure the ground voltage U of the axial flow pump rotor at the positioning mandrel (4), and according to the formula I = U / R, the ground current value I of the rotor can be calculated.

2. The axial flow pump rotor ground current simulation detection method according to claim 1, Characterized in that: A plain bearing (12) is embedded in the rotating plate (3), and the positioning mandrel (4) is inserted into the plain bearing (12).

3. The axial flow pump rotor ground current simulation detection method according to claim 1, Characterized in that: The lead screw (8) is fixedly connected with the connecting cross plate (601) through a lead screw shaft head holding plate (14); the end of the lead screw (8) is fixed inside the lead screw shaft head holding plate (14), and the lead screw shaft head holding plate (14) is threadedly connected with the connecting cross plate (601).

4. The axial flow pump rotor ground current simulation detection method according to claim 1, Characterized in that: The number of the insulating plates (5) is two, and both the connecting vertical rod (6) and the positioning mandrel (4) are fixed between the two insulating plates (6).

5. The method for simulating and detecting the ground current of an axial flow pump rotor according to claim 4, characterized in that: The connecting longitudinal rod (6) and the positioning mandrel (4) are threadedly connected to the two insulating plates (5).

6. The method for simulating and detecting the ground current of an axial flow pump rotor according to claim 5, characterized in that: A stop rod (13) is provided on the connecting longitudinal rod (6); one end of the stop rod (13) is lapped on the support rod (10), and the other end passes through the insulating plate (5) and the connecting longitudinal rod (6) and is locked and fixed by a nut.

7. The method for simulating and detecting the ground current of an axial flow pump rotor according to claim 6, characterized in that: The insulating plate (5) is an epoxy glass cloth board.

8. The method for simulating and detecting the ground current of an axial flow pump rotor according to claim 1, characterized in that: Three support rods (10) are provided between the positioning ring (11) and the positioning plate (9); both ends of the support rod (10) are welded to the positioning ring (11) and the positioning plate (9) respectively.

9. The method for simulating and detecting the ground current of an axial flow pump rotor according to claim 1, characterized in that: Two fixing plates (2) are provided between the driving plate (1) and the rotary plate (3); both ends of the fixing plate (2) are threadedly connected to the driving plate (1) and the rotary plate (3) respectively.

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