JPH02275091A - Supplying method of lubricating water to bearing for vertical shaft pump - Google Patents

Abstract

PURPOSE:To perform lubrication and cooling with lubricating water by closing a lubricating water supply system at a time when a water level of a water absorptive well goes up to more than the specified water level, and performing the lubrication and cooling with self-pumping of a pump, while closing the lubricating water supply system when the water level goes down. CONSTITUTION:At time of operation of a vertical pump 1 whose main shaft 2 is rotated, if a water level of a water absorptive well 6 is more than a pumping start level HWL, pumping operation is performed by an impeller 3. At this time, a valve 9C of a lubricating water supply system 9 is closed by an output signal of a level switch 10, and lubricating water is no longer supplied to each of bearing 5, 8. However, these bearings 5, 8 are lubricated and cooled by self-pumping drawn up by the impeller 3. On the other hand, when the water level goes down to the pumping cutoff level LWL, this level is detected by the level switch 10 and the valve 9C is opened. Consequently, lubricating water is fed to these bearings 5, 8 from a lubricating water supply source 9A of the lubricating water supply system 9 via a pipeline 9B, so that lubrication and cooling are performed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for supplying lubricating water to the bearings of a vertical shaft pump installed at a drainage pump station located in a waterway and used for draining rainwater.

[Prior Art] Ceramic bearings, which are lubricated and cooled by self-pumped water and can continue stable operation, are used as bearings for vertical shaft pumps.

This type of bearing operates dry for a very short period of time immediately after the pump is started, and after this short period of time, it is immediately lubricated and cooled by self-pumped water and begins stable operation. That is, with ceramic bearings, dry operation is limited to a short period of time.

On the other hand, with the rapid progress of urbanization, the amount of rainwater flowing into pumping stations installed in waterways has increased significantly. In such a situation, even if the water level in the water intake well at the drainage pump station drops below the cut-off water level of the vertical shaft pump, dry operation can be continued, and advance standby operation or air control operation that precedes the pump operation status is recommended. We respond by doing things.

[Problems to be Solved by the Invention] The vertical shaft pump used for the above-mentioned advance standby operation and air management operation continues to operate dry for a long time. Therefore, it has not been possible to use a ceramic bearing, which limits the dry operation time to a short time, in a vertical shaft pump that performs advance standby operation or air control operation.

The present invention was developed in view of the above circumstances, and is a vertical shaft pump that can employ ceramic bearings even in vertical shaft pumps that continue dry operation for a long time, such as advance standby operation or air management operation. The purpose is to provide a method for supplying lubricating water to bearings.

[Means for Solving the Problems] In order to achieve the above object, the present invention uses a water level detector to detect a pumping start water level and a pumping cutoff water level specific to a vertical shaft pump, and when the pumping start water level is detected, lubricating water is removed. The supply system is closed to stop the supply of lubricating water to the bearing, and when the pumping cutoff water level is detected, the lubricating water supply system is opened to supply lubricating water to the bearing.

[Effect]

According to the present invention, when the water level rises above the vertical pump pumping start water level, this water level is detected by the water level detector and the lubricating water supply system is closed. The bearings are lubricated and cooled by the self-pumped water of the pump that has started pumping.

Further, when the water level falls below the pumping cutoff water level, this water level is detected by a water level detector and the lubricating water supply system is opened. Therefore, even when the pump is switched to dry operation, lubricating water is supplied to the bearings to lubricate and cool them, allowing stable operation to continue.

[Example] Embodiments of the present invention will be described below based on the drawings.

FIG. 1 shows a vertical shaft pump configured to supply lubricating water to bearings by the method according to the present invention. In the figure, the main shaft 2 of the vertical shaft pump 1 is fixed to the base of a guide vane 4 above an impeller 3. It is rotatably supported by a bearing 5 and a bearing 8 fixed at approximately the same height level as the floor 7 of the water absorption well 6.

It is rotationally driven by a prime mover (not shown).

The bearings 5.8 are each made of ceramics such as silicon carbide, and are each provided with a lubricating water supply system 9.
Lubricant water for lubrication and cooling is supplied from the

The lubricating water supply system 9 includes a lubricating water supply source 9A, a pipe line 9B that communicates the lubricating water supply source 9A with the bearings 5 and 8, and a valve such as a solenoid valve or an electric ball valve interposed in the pipe line 9B. It is composed of 9C. Therefore, when the valve 9C is opened, lubricating water is supplied from the lubricating water supply source 9A to the bearings 5.8, and when the valve 9C is closed, the supply of lubricating water to the bearings 5, 8 is stopped.

The water level detector 10 is the pumping start water level HW specific to the vertical shaft pump 1.
The valve 9 is for detecting the pumping cutoff water level LWL and is composed of a float type detector, and the water level detection signal from this is interposed in the pipe line 8B of the lubricating water supply source 9A.
When the water level reaches the pumping start water level HWL or higher, the valve 9C is closed, and when the water level falls below the pumping cutoff water level LWL, the valve 9C is opened to supply lubricating water. Lubricating water is supplied from source 9A to each of the bearings 5.8 through line 8B.

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

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 water suction well 6 is equal to or higher than the pumping start water level HWL, a pumping operation is performed in which water is sucked up by the impeller 3. In this case, the valve 9C is closed by the signal output from the water level detector 10, and although no lubricating water is supplied to the bearings 5 and 8, the bearings 5 and 8 are lubricated by the self-pumped water sucked up by the impeller 3. and will be cooled.

Even if the water level drops below the pumping start water level HWL due to continued pumping operation, the valve 9C remains closed until the water level drops to the pumping cutoff water level LWL, and the bearings 5 and 8 are closed due to self-pumping water. continues to be lubricated and cooled.

When the water level drops to the pumping cutoff water level LWL, vertical shaft pump 1
is switched to dry operation. At the same time, this water level is detected by the water level detector IO, and a signal outputted from the water level detector IO causes the valve 9C to open. As a result, the lubricating water supply system 9
Lubricating water is supplied from the lubricating water supply source 9A to the bearings 5, 8 through the pipe 9B, and this performs lubrication and cooling. Therefore, the vertical shaft pump l is switched to dry operation, and the bearings 5, 8 are pumped by self-pumping water. Even if it is no longer lubricated,
The lubricating water supplied from the lubricating water supply system 9 provides lubrication and continues stable operation.

As the dry operation continues, the water level in the water intake well 6 rises and reaches the pumping start water level HWL, and as described above, the pumping operation is switched to, and the bearings 5.8 are lubricated by the self-pumped water.

In this way, during the dry operation of the vertical shaft pump l, the bearings 5 and 8 are lubricated and cooled by the lubricating water supplied from the lubricating water supply system 9, so that the dry operation continues for a long period of time, such as advance standby operation or Ceramic bearings 5 and 8 can also be employed in the vertical shaft pump 1 that performs air management operation.

[Effects of the Invention] As explained above, according to the present invention, when the water level reaches such a level that the bearing cannot be lubricated by self-pumped water, the lubricating water is stopped by a signal from the water level detector that detects the current water level. The supply system can be opened and the bearings can be lubricated and cooled with the lubricating water from this system, allowing stable operation to continue, allowing advance standby operation and air control operation, which were previously considered impossible. Ceramic bearings can also be used in vertical shaft pumps, improving versatility.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of a vertical shaft pump applied to the method according to the present invention. 1...Vertical shaft pump 2...Main shaft 5.8...Ceramic bearing 9...Lubricating water supply system 10...Water level detector HWL...Pumping start water level LWL...Pumping cutoff water level Patent application Person Kubota Iron Works Co., Ltd. Agent Patent Attorney Takashi Suzue −

Claims (1)

[Claims] (1) A method of supplying lubricating water to the ceramic bearing that pivotally supports the main shaft of a vertical shaft pump, in which a water level detector is used to detect the pumping start water level and pumping cutoff water level specific to the vertical shaft pump, and the pumping start water level is When the lubricating water supply system is detected, the lubricating water supply system is closed to stop the lubricating water supply to the bearing,
A method for supplying lubricating water to a bearing of a vertical shaft pump, characterized in that a lubricating water supply system is opened when a pumping cutoff water level is detected to supply lubricating water to the bearing.