JPH0792075B2 - Lubrication water supply method for bearings of vertical pumps - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for supplying lubricating water to a bearing of a vertical shaft pump installed in a drainage station installed in a waterway and used for draining rainwater and the like.

[Prior Art] As a bearing of a vertical shaft pump, a ceramic bearing that is lubricated and cooled by self-pumping water and can continue stable operation is adopted.

In this type of bearing, the dry operation is performed for a very short time immediately after the trajectory of the pump, and after this short time, it is immediately lubricated and cooled by the self-lifting water to start the stable operation. That is, in the ceramic bearing, the dry operation is limited to a short time.

On the other hand, with the rapid progress of urbanization, the inflow of rainwater to pumping stations located in waterways has increased significantly. In such a situation, even if the water level of the suction well at the drainage pump station drops below the pumping cutoff water level of the vertical shaft pump, the dry operation is continued, and the pre-standby operation and the air management operation that precede the operation state of the pump are performed. It is handled by doing.

[Problems to be Solved by the Invention] In the vertical shaft pump used for the preceding standby operation or the air management operation, the dry operation is continued for a long time. Therefore, it has not been possible to employ a ceramic bearing whose dry operation time is limited to a short time in a vertical shaft pump that performs a preceding standby operation and an air management operation.

The present invention has been made in view of the above circumstances, and it is possible to adopt a ceramic bearing even in a vertical shaft pump in which a dry operation is continued for a long time, such as a preceding standby operation or an air management operation, Moreover, it is an object of the present invention to provide a method of supplying lubricating water to a bearing of a vertical shaft pump that can efficiently supply the lubricating water and can accurately determine whether or not to supply the lubricating water.

[Means for Solving the Problems] In order to achieve the above object, the present invention is configured such that when the water level is above the pumping start water level, pumping operation is performed, and when the water level is below the pumping cutoff water level, it is switched to dry operation. A method of supplying lubricating water to a ceramics bearing rotatably supporting a main shaft of a vertical shaft pump by a lubricating water supply system that is interposed in a pipeline connecting the lubricating water supply source and the bearing, Pumping and pumping cutoff state detection means, which is arranged inside the discharge pipe of a vertical pump, opens when passage of pumping water and closes when pumping off is performed by detecting the open and closed positions of the check valve by switches. Detects the pumping state and pumping-off state of the vertical pump,
When the pumping state is detected by opening the check valve, the lubricating water supply system is closed, and the supply of lubricating water to the bearing is stopped.
In addition, the lubricating water supply system is opened to supply the lubricating water to the bearing when the pumping water cutoff state is detected by closing the check valve.

[Operation] According to the present invention, during the pumping operation of the vertical shaft pump, the pumping state is detected by opening the check valve provided in the discharge pipe of the vertical axis pump, and the lubricating water supply system is closed to lubricate the bearing. Water supply is stopped. Here, the bearing is lubricated and cooled by the self-pumping of the pump that started the pumping operation.

Also, when the pump is switched to dry operation because the water level drops below the pumping cutoff water level, the pumping and pumping shutoff means close the check valve to detect the pumping interruption state and open the lubricating water supply system. It for that reason,
Even if the pump is switched to the dry operation, the lubricating water is directly supplied into the bearing to be lubricated and cooled, so that the stable operation can be continued.

Of course, if the water level when the pump is operated is less than the pumping start water level, the pumping operation is not performed, so the check valve is closed, the lubricating water supply system is opened, and the lubricating water is stored in the bearing. Directly supplied.

As described above, the lubrication water supply system is opened only when the check valve in the discharge pipe closes and the pumping is shut off. Therefore, it is possible to eliminate the waste of the lubrication water supply and the fluctuation of the water level. It is possible to accurately determine the necessity of supplying the lubricating water without being affected.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a vertical shaft pump for supplying lubricating water to a bearing by the method according to the present invention. In the drawing, a main shaft 2 of the vertical shaft pump 1 is fixed to a base of a guide vane 4 above an impeller 3. The bearing 5 is rotatably supported by a bearing 8 fixed at substantially the same level as the floor surface 7 of the water absorption well 6, and is rotationally driven by a prime mover (not shown).

The bearings 5 and 8 are each made of ceramics such as silicon carbide, and lubricating water for lubricating and cooling is supplied to each from a lubricating water supply system 9.

The lubricating water supply system 9 includes a lubricating water supply source 9A and this lubricating water supply source
It is composed of a pipe line 9B for communicating 9A with the bearings 5 and 8, and a valve 9C such as an electromagnetic valve or an electric ball valve provided in the pipe line 9B. Therefore, when the valve 9C is opened, the lubricating water supply source 9A supplies the lubricating water to the bearings 5 and 8, and when the valve 9C is closed, the supply of the lubricating water to the bearings 5 and 8 is stopped.

The discharge pipe 1A of the vertical shaft pump 1 is provided with pumping and pumping cutoff state detecting means 10. The pumping and pumping cutoff state detecting means 10 is for detecting whether the vertical shaft pump 1 is in a pumping operation state or a dry operation state, and as shown in FIGS. Piping 1A
Of the plate-like check valve 10A, which is arranged on the downstream side of the valve seat 1B formed across the inside of the valve seat and corresponds to a pair of upper and lower through holes 1b, 1b formed in the valve seat 1B. 10A and these check valves 10A, 1
The upper end base of 0A is fitted and fixed, and the discharge pipe 1A
Valve shafts 10B and 10B horizontally and rotatably supported by liquid-tight shafts
And the projection 1 that is externally fitted and fixed to the pipe extension portion of each valve shaft 10B, 10B.
0C and the protrusion 10C are arranged on the rotation locus, for example, 1
It is composed of a pair of micro switches 10D and 10E. Then, the signals output from the micro switches 10D and 10E are input to the controller 11, from which the lubricating water supply system 9
A signal is output to the valve 9C to open and close the valve 9C.

Next, a procedure for supplying lubricating water to the bearings 5 and 8 will be described.

In the operating state of the vertical shaft pump 1 in which the main shaft 2 is rotationally driven, if the water level of the suction well 6 is equal to or higher than the pumping start water level HWL, the pumping operation in which water is pumped up by the impeller 3 is performed. In this case, the pumped water passes through the through holes 1b, 1b formed in the valve seat 1B of the discharge pipe 1A, so that the check valves 10A, 10A
Is opened as shown by the phantom line in FIG. 2, whereby the protrusion 10C presses the microswitch 10E as shown by the phantom line in FIG. 4, and a signal is output from this to the controller 11,
The valve 9C is closed by the signal output from the controller 11. Therefore, although the lubricating water is not supplied to the bearings 5 and 8, the bearings 5 and 8 are lubricated and cooled by the self-lifted water sucked up by the impeller 3.

When the water level drops to the pumping cutoff water level LWL, the vertical shaft pump 1 is switched to dry operation. That is, water stops flowing in the discharge pipe 1A. Therefore, the check valves 10A, 10A rotate by their own weight to the closed position shown by the solid line in FIG. 2 to prevent backflow from the downstream side, and as shown by the solid line in FIG. The switch 10E is pressed, a signal is output from this to the controller 11, and the valve 9C is opened by the signal output from the controller 11. As a result, the lubricating water is supplied from the lubricating water supply source 9A of the lubricating water supply system 9 to the bearings 5 and 8 through the pipe 9B, thereby performing lubrication and cooling. Therefore, the vertical pump 1 is switched to the dry operation,
Even if the bearings 5 and 8 are no longer lubricated by self-pumping water, they are lubricated by the lubricating water supplied from the lubricating water supply system 9,
It is intended to continue stable operation. Of course, when the water level when the vertical pump 1 is operated is less than the pumping start water level HWL, the pumping cutoff state in which the pumping water does not pass through the discharge pipe 1A is detected and the lubricating water supply system 9 is opened to supply the lubricating water. Bearing from source 9A
Lubricating water is supplied to 5,8.

When the water level of the suction well 6 rises due to the continuation of the dry operation and reaches the pumping start water level HWL, the pumping operation is switched as described above, and the bearings 5 and 8 are lubricated by the self pumping.

As described above, during the dry operation of the vertical shaft pump 1, the lubricating water supplied from the lubricating water supply system 9 lubricates and cools the bearings 5 and 8. The ceramic bearings 5 and 8 can also be adopted in the vertical pump 1 that performs the air management operation.

Incidentally, for example, it may be possible to judge the necessity of supplying the lubricating water only from the water level before the operation of the vertical shaft pump 1, but in this case, the lubricating water supply efficiency is not good. That is, even if the water level before the operation of the pump 1 is lower than the upper edge of the impeller 3, for example, pumping is started by the start of the operation of the pump 1. At this time, the supply of the lubricating water is detected by detecting the water level. Is started and this is continued until the operation of the pump 1 is stopped, so that the lubricating water is unnecessarily supplied. On the other hand, as in the above embodiment, the vertical shaft pump 1
Pumping and pumping cutoff detection means installed in the discharge pipe 1A
By determining the necessity of supplying the lubricating water according to 10, the lubricating water can be reliably supplied only when the pumping is cut off. Further, since it is not affected by the fluctuation of the water level at all, the necessity of supplying the lubricating water can be accurately determined.

Although the pair of microswitches 10D and 10E is used in the above embodiment, only the microswitch 10D may be used and the microswitch 10E may be omitted.

[Effects of the Invention] As described above, according to the present invention, the switch detects the opening / closing of the check valve that is provided in the discharge pipe of the vertical pump and opens when pumping up and closes when pumping off. The pumping and pumping cutoff detection means are used to detect the pumping condition and pumping cutoff condition, respectively, and the lubricating water supply system is opened at the time of dry operation condition where the bearing cannot be lubricated by self pumping, that is, when the pumping cutoff condition is detected. Since the bearings can be lubricated and cooled by the lubricating water from here to continue stable operation, ceramics can be used for vertical axis pumps that have not been able to be adopted in the past, and for vertical standby pumps that perform air management operation. It is possible to use bearings and improve versatility.

Moreover, since it is possible to determine whether or not the supply of lubricating water is necessary by detecting the pumping and pumping cutoff states in the discharge pipe of the vertical pump, the supply of lubricating water is limited to the pumping cutoff state. It is possible to efficiently supply lubricating water without wasteful supply of water. Moreover, it is possible to accurately supply / stop the lubricating water without being affected by the fluctuation of the water level.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of a vertical shaft pump applied to a method according to the present invention, FIG. 2 is an enlarged vertical sectional view of an essential part, FIG. 3 is a plan view of FIG. 2, and FIG. In Fig. 2
It is sectional drawing which follows the IV-IV line. 1 …… Vertical pump 1A …… Discharge pipe 2 …… Spindle 5,8 …… Ceramics bearing 9 …… Lubrication water supply system 9A …… Lubrication water supply source 9B …… Pipe line 9C …… Valve 10 …… Pumping and pumping Shut-off state detection means 10A …… Check valve 10C, 10D …… Switch HWL …… Pump start water level LWL …… Pump cutoff water level

Claims (1)

[Claims] Claim: What is claimed is: 1. A ceramic bearing for supporting a main shaft of a vertical shaft pump, which is constructed so that a pumping operation is performed when the water level is higher than the pumping start water level and a dry operation is switched when the water level is lower than the pumping cutoff water level. A method of supplying lubricating water by means of a lubricating water supply system which is interposed in a pipe line that connects the lubricating water supply source and the bearing, and which is arranged inside the discharge pipe of the vertical shaft pump to pass the pumping water. Open the valve,
In addition, the pumping and pumping cutoff state detection means that detects the open and closed positions of the check valve that is closed by pumping cutoff respectively detects the pumping state and pumping cutoff state of the vertical axis pump, and the check valve When the pumping state is detected by opening the valve, the lubricating water supply system is closed to stop the supply of lubricating water to the bearing, and when the check valve is closed, the lubricating water supply system is closed. Open it up,
Lubricating water is supplied to the bearing, and a method for supplying lubricating water to the bearing of the vertical shaft pump is characterized.