Pump condition monitoring device and pump equipped with same

Abstract

To provide a state monitoring technique for pump that is applicable to pump state monitoring, remote monitoring, and an information transmission device.SOLUTION: A state monitoring device 10 for pump is used for a pump 1 such that a liquid contact part of a casing 5 has its inner surface lined with soft rubber or a liner 3 made of soft rubber is included inside the casing 5 so as to monitor a state of the pump 1, and also has: pressure sensors 20A, 20B, 20C, and 20D which are embedded at a plurality of places in the soft rubber constituting a lining or liner 3 while isolated from the inner surface of the liquid contact part of the lining or liner 3; and a controller 30 which detects information associated with the state of the pump 1 based upon pressure information acquired by the pressure sensors 20A, 20B, 20C, and 20D at the plurality of places.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a technique for monitoring the state of a pump. [Background technology]

[0002] For example, slurry pumps that pump high-concentration or corrosive slurries can suffer from early wear of wetted parts, blockages or foreign matter getting caught in the pump, and a significant drop in performance. For this reason, it is necessary to be prepared for unexpected maintenance on a regular basis.

[0003] On the other hand, if parts are replaced early in order to avoid unexpected issues, the optimal maintenance intervals are often missed. As a result, both users and manufacturers must always have a large inventory of parts and maintenance support personnel, resulting in high maintenance and running costs. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2008-261668 A (paragraphs 0011 and 0016) Summary of the Invention [Problem to be solved by the invention]

[0005] In response to this, it has long been common to attach pressure gauges to the suction and discharge piping connected to a pump in order to monitor the pump's condition (see, for example, Patent Document 1), but in order to obtain more information about the operating condition, it is necessary to attach a pressure sensor to the liquid-contacting part of the pump or as close to the liquid-contacting part as possible.

[0006] However, in high-concentration / corrosive slurry pumps, there is a problem that wear progresses from the pressure sensor mounting hole, making it practically difficult to mount a pressure sensor on the liquid-contacting part of the slurry pump itself.

[0007] Therefore, the present invention has been made with attention to these problems, and it is an object of the present invention to provide a pump condition monitoring device and a pump equipped with the same, which are capable of monitoring the condition of the pump itself, even in the case of a slurry pump that pumps high-concentration slurry or corrosive slurry. [Means for solving the problem]

[0008] In order to solve the above problems, one embodiment of the present invention provides a pump condition monitoring device that is used in a pump in which the inner surface of the liquid-contacting part of the casing is lined with soft rubber or a soft rubber liner is contained inside the casing, and that monitors the condition of the pump, and is characterized in having pressure sensors embedded in multiple locations in the soft rubber and spaced apart from the inner surface of the liquid-contacting part of the soft rubber, and a condition information detection unit that detects information related to the condition of the pump based on pressure information acquired by the pressure sensors at multiple locations.

[0009] According to one aspect of the present invention, a pump condition monitoring device includes pressure sensors embedded in soft rubber and spaced apart from the liquid contact surface of a soft rubber lining or liner, which are arranged at multiple locations on the inner surface of the liquid contact portion, and a condition information detection unit can detect information related to the condition of the pump based on pressure information obtained by the pressure sensors at multiple locations. Therefore, even in the case of a slurry pump that pumps high-concentration or corrosive slurry, if the inner surface of the casing that comes into contact with the liquid is lined with soft rubber or a soft rubber liner is incorporated inside the casing, then by using a pump condition monitoring device according to one embodiment of the present invention on the pump, the condition of the pump itself, such as abnormalities in the internal pressure of the pump, deterioration of the pump performance, and wear status, can be monitored.

[0010] In order to solve the above problems, a pump according to one aspect of the present invention is a pump in which the inner surface of the liquid-contacting part of the casing is lined with soft rubber or a soft rubber liner is contained inside the casing, and is characterized in that the pump is equipped with a pump condition monitoring device according to one aspect of the present invention. According to the pump according to an aspect of the present invention, since the pump status monitoring device according to an aspect of the present invention is equipped, the status of the pump itself can be monitored. Effect of the Invention

[0011] As described above, the present invention allows the condition of the pump itself to be monitored. [Brief description of the drawings]

[0012] [Figure 1] 1 is a schematic vertical cross-sectional view illustrating an embodiment of a pump equipped with a pump condition monitoring device according to an aspect of the present invention. [Diagram 2] 2A and 2B are schematic diagrams of a pressure sensor used in the pump condition monitoring device of FIG. 1, in which FIG. 2A is a front view and FIG. 2B is a ZZ sectional view of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the drawings as appropriate. In this embodiment, a pump condition monitoring device according to an embodiment of the present invention is installed in a centrifugal pump used as a high-concentration / corrosive slurry pump. It should be noted that the drawings are schematic, and therefore the relationship and ratio between thickness and planar dimensions may differ from the actual relationship and ratio between the drawings. Furthermore, the embodiments described below are merely examples of devices and methods for embodying the technical ideas of the present invention, and the technical ideas of the present invention do not limit the materials, shapes, structures, arrangements, etc. of the components to the embodiments described below.

[0014] 1, this centrifugal pump 1 includes a casing 5 provided in front of a frame (not shown). The frame is provided with a bearing portion that rotatably supports a drive shaft 4 via bearings spaced apart from each other in the axial direction.

[0015] A semi-open impeller 2 housed inside a casing 5 is fixed to the tip of the drive shaft 4. The impeller 2 has a substantially disk-shaped base portion 2b, and a plurality of blades 2c protruding axially forward are integrally formed with the base portion 2b.

[0016] The casing 5 has a main body portion 5b at the rear and a suction portion 5a at the front. The suction portion 5a and the main body portion 5b are fixed to each other with bolts and nuts (not shown), and an accommodation space for the impeller 2 is defined inside.

[0017] A discharge port 5t is formed at the top of the main body 5b of the casing 5, and a discharge piping 8 is connected to the discharge port 5t. A front cover 6 is attached to the front of the suction portion 5a of the casing 5, and a suction port 6n is formed in the front cover 6 and protrudes forward along the axial direction, and a suction piping 7 is connected to the suction port 6n.

[0018] A liner 3 that covers the entire inner surface of the liquid-contacting part is attached inside the casing 5. The inner surface of the liquid-contacting part of the casing 5 may be lined with soft rubber instead of the liner 3. In other words, the present invention is applicable to pumps in which the inner surface of the liquid-contacting part of the casing is lined with soft rubber or in which a soft rubber liner is incorporated inside the casing.

[0019] Here, the soft rubber that constitutes the lining or the liner is selected from natural rubber or various synthetic rubbers (e.g., acrylonitrile-butadiene rubber (NBR), butyl rubber (isobutene-isoprene rubber (IIR)), etc.) according to the properties of the liquid being pumped (e.g., the corrosiveness of the slurry, etc.).

[0020] The hardness of the soft rubber constituting the lining or liner is preferably a type A durometer hardness of 70° or less (JIS K6253) as measured by a durometer hardness tester, and the soft rubber preferably has a small compression set, and sponge-like rubber or other rubber containing air bubbles is not suitable.

[0021] In this embodiment, the soft rubber constituting the liner 3 has better abrasion resistance than metal materials for fine particle slurries with an average particle size of approximately 1 mm or less. In addition, the soft rubber constituting the liner 3 can also handle highly concentrated and corrosive slurries by selecting an appropriate soft rubber material for corrosion resistance and chemical resistance. For this reason, a slurry pump with a rubber lining on the inner surface of the liquid-contacting part or a soft rubber liner inside the casing is suitable for highly concentrated and corrosive slurries.

[0022] Here, the condition monitoring device 10 of this embodiment has pressure sensors 9A and 9B for the piping section, a plurality of thin pressure sensors 20A, 20B, 20C, and 20D, and a controller 30 constituting an operation state information detection section. The controller 30 is an information processing device including a computer, and is configured to be able to execute a predetermined pump operation state information detection process and monitor the operation state of the pump, such as an abnormality in the internal pressure of the pump, a decrease in pump performance, and a wear state.

[0023] More specifically, in this embodiment, a piping pressure sensor 9A is attached to the suction pipe 7, and a piping pressure sensor 9B is attached to the discharge pipe 8. Furthermore, thin pressure sensors 20A, 20B, 20C, and 20D are embedded in a plurality of locations (four locations in this example) on the inner surface of the liquid-contacting portion of the casing 5, spaced at arbitrary distances from the liquid-contacting surface of the liner 3 made of soft rubber.

[0024] In this embodiment, by arranging pressure sensors 20A, 20B, 20C, and 20D at multiple arbitrary locations on the inner surface of the liquid-contacting portion, detailed information related to the operating state of the centrifugal pump 1 can be detected based on pressure information acquired by the pressure sensors 20A, 20B, 20C, and 20D at multiple locations.

[0025] As a result, the controller 30 is able to detect abnormalities in the pump's internal pressure, deterioration of the pump's performance, pump wear, etc. by executing the pump operating status information detection process, and output the detected information to a display device such as a monitor.

[0026] Here, in the pump operation status information detection process executed by the controller 30, the pump operation status is not necessarily monitored and diagnosed using absolute values ​​such as pressure values, but can be monitored and diagnosed by evaluating fluctuations due to wear and corrosion from when the pump was new relatively to the initial pressure value when the pump was new. Further, the pressure sensors 20A, 20B, 20C, and 20D are not particularly limited, but it is preferable to use a film-like thin-film pressure-sensitive sensor (eg, manufactured by Interlink Electronics) having a thickness of about 0.2 mm.

[0027] This type of pressure-sensitive sensor, like the pressure-sensitive sensor 20 shown in Fig. 2, includes a two-wire pressure-sensitive section 20a with a diameter of about φ5 mm and no moving parts, and a gusset section 20f. As shown in Fig. 2(b), the pressure-sensitive section 20a has a structure in which an upper adhesive section 20b, an upper substrate 20c, an internal adhesive section 20d, and a lower substrate 20e are laminated in this order from the top side. The portion formed by the internal adhesive section 20d and the lower substrate 20e is the gusset section 20f including wiring led out from the pressure-sensitive section 20a.

[0028] 2 has a characteristic that the electrical resistance decreases linearly as the pressure applied to the pressure-sensitive portion 20a increases. Therefore, it can be used as a pressure sensor that has a low operating pressure, a wide sensitivity range, is thin, and is durable and resistant to moisture, dirt, etc.

[0029] In this embodiment, pressure sensors 20A, 20B, 20C, and 20D having the same configuration as the pressure sensor 20 shown in Fig. 2 are embedded at multiple positions (four positions in this example) as shown in Fig. 1 at any distance from the inner surface of the soft rubber. That is, the first pressure sensor 20A is embedded at a position facing the front end of the blade 2c of the impeller 2. This makes it possible to detect the fluctuation state of the clearance.

[0030] The second pressure sensor 20B is embedded in the suction port 6n of the front cover 6 or in a position nearby it (a corner of the suction port 6n in this embodiment). The third pressure sensor 20C is embedded in the lowest position of the casing 5 or in a position nearby it (the lowest position in this embodiment). The fourth pressure sensor 20D is embedded in the discharge port 5t of the casing 5 or in a position nearby it (a position nearby the discharge port 5t in this embodiment).

[0031] When the impeller 2 wears and the pump performance of the centrifugal pump 1 decreases, the pressure drops significantly mainly at the pressure sensor 20D near the discharge port 5t. Also, when the wear of the liner 3 progresses, the pressure sensors of the pressure sensors 20A, 20B, 20C, and 20D in the worn parts become exposed and cause electrical failure, so that it can be detected at that point that the wear has reached the embedded position of the pressure sensors.

[0032] Furthermore, the remaining time until the hole finally penetrates the liner 3 can be predicted from the positions where the pressure sensors 20A, 20B, 20C, and 20D are embedded and the elapsed time until the electrical failure occurs. Therefore, according to the condition monitoring device 10 of this embodiment, the parts replacement cycle of the centrifugal pump 1 can be optimized. In addition to the pressure information obtained from these pressure sensors 20A, 20B, 20C, and 20D, by adding pressure information obtained from pressure sensors 9A and 9B for the piping section and data obtained from other sensors such as temperature sensors, even more detailed operating conditions of the centrifugal pump 1 can be obtained.

[0033] As described above, the pump condition monitoring device 10 of this embodiment is a technology that can be applied to general pump condition monitoring, but as in this embodiment, in a centrifugal pump 1 such as a slurry pump for high concentration / corrosive substances, it is suitable for monitoring the pump operation condition such as abnormality in the pump's internal pressure, deterioration of the pump's performance, wear status, etc. It is particularly effective for the maintenance of slurry pumps exposed to harsh liquid properties.

[0034] Furthermore, the pump status monitoring device 10 of this embodiment can be used to remotely monitor the centrifugal pump 1, and can be used in conjunction with other devices to provide information such as maintenance information for the centrifugal pump 1, such as a slurry pump. The pump status monitoring device and the pump equipped therewith according to the present invention are not limited to the above embodiment, and various modifications are possible without departing from the spirit of the present invention. [Explanation of symbols]

[0035] 1. Centrifugal pump 2 Impeller 3 Liner 4 Drive shaft 5 Casing 6 Front cover 7 Suction piping 8 Discharge piping 9A, 9B (for piping) pressure sensors 10 Condition monitoring device 20, 20A, 20B, 20C, 20D Pressure Sensor 30 Controller (Status Information Detection Unit)

Claims

1. A status monitoring device for use in a pump in which the inner surface of a casing that comes into contact with liquid is lined with soft rubber or in which a soft rubber liner is contained inside the casing, the status monitoring device monitoring the status of the pump, comprising: a sensor embedded in the soft rubber constituting the lining or the liner at a distance from an inner surface of the lining or the liner in contact with the liquid; a status information detection unit that monitors an operating status of the pump based on the current flow information acquired by the sensor; having The sensor acquires the current flow information by itself, the sensor being embedded in one location; The status information detection unit, when acquiring power-on information opposite to that during normal operation of the sensor (information of a non-powered state if the normal operation is a powered state, and information of a powered state if the normal operation is a non-powered state), predicts the remaining time until the lining or the liner is penetrated based on the position where the sensor is embedded and the elapsed time until the opposite power-on information is acquired.

2. A condition monitoring device for a pump as described in claim 1, wherein the sensors are embedded in multiple locations in the lining or the soft rubber that constitutes the liner.

3. The pump includes an impeller having a plurality of blades housed inside the casing, Among the plurality of sensors, The first sensor is embedded in a position facing a front end of the impeller blade, The second sensor is embedded in the casing at or near the suction port, a third sensor embedded in the casing at or near the lowest position; 3. The pump condition monitoring device according to claim 2, wherein the fourth sensor is embedded at or near the discharge port of the casing.

4. A pump in which the inner surface of the liquid-contacting part of the casing is lined with soft rubber or a soft rubber liner is contained inside the casing, A pump comprising the pump condition monitoring device according to any one of claims 1 to 3.

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