JPH07259792A - Lubricating water feeding method for pump and vertical shaft pump - Google Patents

Abstract

PURPOSE:To prevent the occurrence of burning of the slide part of a main shaft by feeding lubricating water to the slide part of the main shaft even during reversing after the stop of a pump. CONSTITUTION:A circulation water feed system for the slide part 5 of a main shaft comprises an external water source 10A consisting of an elevated water tank; a first line 10B to feed circulation water from the external water source 10A; a second line 10E having an intake port 10e situated upper stream from a delivery valve 12 located between a delivery pipe 8 and a delivery piping 11 and connected to the downstream side of the check valve 10D of the first line 10B; and a third line 10H having an intake port 10h in a position situated right downstream from the delivery valve 12 and connected to a place situated downstream from the check valve 10G of the second line 10E. During pumping-up operation of a pump, lubricating water is inputted through the intake port 10e situated upper stream from the delivery valve 12 and fed to the slide part 5 of the main shaft. During the stop of a pump in a state that the delivery valve 12 is in a closed state, lubricating water is inputted through the intake port 10h in the vicinity of a position situated downstream from the delivery valve 12 and fed to the slide part 5 of the main shaft.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for supplying lubricating water to a sliding portion of a main shaft such as a shaft seal portion or a bearing portion of a pump, and a vertical shaft pump having a lubricating water supply function. Regarding

[0002]

2. Description of the Related Art Conventionally, in a vertical shaft pump 1 shown in FIG. 2, a main shaft 2 is rotatably supported by a sliding portion 5 of the main shaft. The sliding portion 5 of the main shaft is, for example, a lower bearing 5 fixed to the central boss portion of the guide vane 4 above the impeller 3.
A, an upper bearing 5B fixed at a height level above the floor surface 7 of the water intake well 6, and an intermediate bearing 5C fixed in the discharge pipe (pumping pipe) 8 between the lower bearing 5A and the upper bearing 5B. And a shaft seal portion 5D such as a gland packing or a mechanical seal. The main shaft 2 is rotationally driven by a prime mover 9 such as a motor or an engine connected to the upper end of the main shaft 2. Lower bearing 5A, upper bearing 5B
The intermediate bearing 5C and the intermediate bearing 5C are made of ceramics such as silicon carbide or rubber, and are supplied with lubricating water for lubrication and cooling from the lubricating water supply system 10. The lubricating water supply system 10
For example, an external water source 10A composed of an elevated water tank, a first pipeline 10B for supplying lubricating water from the external water source 10A to the shaft sealing portion 5D and the upper bearing 5B, and the first pipeline 10B.
Has a valve 10C and a check valve 10D such as a solenoid valve and an electric ball valve that are installed on the upstream side of the discharge valve 12 that is interposed between the discharge pipe 8 and the discharge pipe 11. The check valve 10 in the first conduit 10B is provided with the port 10e.
The second conduit 10E connected to the downstream side of D
The pipe 10E has a structure in which a valve 10F such as an electromagnetic valve or an electric ball valve and a check valve 10G are provided.

Therefore, when the vertical shaft pump 1 is started, by opening the valve 10C of the first pipe line 10B in the lubricating water supply system 10, lubricating water is supplied from the external water source 10A to the shaft seal portion 5D and the upper bearing 5B. , This lubricating water is a protective tube 1
It is supplied to the intermediate bearing 5C and the lower bearing 5A through the inside of 3. On the other hand, when pumping is started by activating the vertical shaft pump 1, the valve 10F of the second pipe line 10E is opened, so that pumped water (self-pressurized water) in the discharge pipe 8 is discharged from the intake port 10e to the second pipe. It is taken into the passage 10E, is supplied to the shaft seal portion 5D and the upper bearing 5B through the first pipe passage 10B, and is further supplied to the protection pipe 1.
It is supplied to the intermediate bearing 5C and the lower bearing 5A through the inside of 3 to lubricate and cool them. In addition,
The valve 10C of the first conduit 10B is closed after confirming that self-pressurized water is flowing through the second conduit 10E by a flow relay (not shown) or the like.

On the other hand, by stopping the prime mover 9 and closing the discharge valve 12, the operation of the vertical pump 1 is stopped. However, when the operation of the vertical shaft pump 1 is stopped, the water in the discharge pipe 8 may fall into the water absorption well 6, and the impeller 3 and the main shaft 2 may be reversed at high speed. However, in the conventional vertical pump 1, since the water in the discharge pipe 8 falls into the suction well 6,
Since the intake port 10e of the second conduit 10E opens at the negative pressure portion in the discharge pipe 8, the lubricating water cannot be taken in and supplied. As a result, the lower bearing 5A and the upper bearing 5
B, the intermediate bearing 5C, the shaft seal portion 5D, and other sliding portions 5 of the main shaft may be burned out.

[0005]

The problem to be solved is that the supply of lubricating water to the sliding portion of the main shaft is cut off during reverse rotation after the pump is stopped, so that the sliding portion of the main shaft burns out. This is a point of concern.

[0006]

According to the invention of claim 1, a discharge valve is provided between the discharge pipe and the discharge pipe, and the discharge pipe is raised above the position of the discharge valve. In, the intake port of the lubricating water supply system of the pump is provided at both the upstream side and the downstream vicinity of the discharge valve, and during pumping operation of the pump, the lubricating water is taken in from the intake port on the upstream side of the discharge valve. Of the pump, and when the pump is stopped when the discharge valve is closed, the lubricating water is taken from the intake port near the downstream side of the discharge valve and supplied to the sliding part of the main shaft. The objective of preventing burnout of the sliding portion of the spindle was achieved by supplying lubricating water to the sliding portion of the spindle even when reversing after stopping.

According to a second aspect of the present invention, there is provided a vertical shaft pump in which a discharge valve is provided between the discharge pipe and the discharge pipe, and the discharge pipe is raised above the position of the discharge valve.
At the upstream and downstream sides of the discharge valve, intake ports of a lubricating water supply system for supplying lubricating water to the sliding parts of the main shaft are provided at the time of reverse rotation after stopping the vertical shaft pump. Also in the above, the purpose of preventing burnout of the sliding portion of the spindle was achieved by supplying lubricating water to the sliding portion of the spindle.

[0008]

According to the invention of claim 1, since water remains inside the discharge pipe even after the pump with the discharge valve closed is stopped, the lubricating water is taken in from the intake port near the downstream side of the discharge valve. Can be supplied to the sliding part of the spindle.

According to the second aspect of the present invention, since water remains inside the discharge pipe even after the vertical pump with the discharge valve closed is stopped, the lubricating water is taken from the intake port near the downstream side of the discharge valve. It can be supplied to the sliding part of the main shaft.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic configuration diagram of a vertical shaft pump to which the present invention is applied. A main shaft 2 of the vertical shaft pump 1 is rotatably supported by a sliding portion 5 of the main shaft. Vertical shaft 1 main shaft 2
Is a lower bearing 5A fixed to the central boss portion of the guide vane 4 on the upper side of the impeller 3, an upper bearing 5B fixed to a height level above the floor surface 7 of the water absorption well 6, a lower bearing 5A and an upper portion. An intermediate bearing 5C fixed in the discharge pipe (pumping pipe) 8 between the bearings 5B and a shaft sealing portion 5D such as a gland packing or a mechanical seal are included. The main shaft 2 is rotationally driven by a prime mover 9 such as a motor or an engine connected to the upper end of the main shaft 2. The bearing lower part 5A, the upper bearing 5B and the intermediate bearing 5C are each made of ceramics such as silicon carbide or rubber, and are supplied with lubricating water for lubrication and cooling from the lubricating water supply system 10, respectively. Has become.

The lubricating water supply system 10 is a first external water source 10A, which is, for example, an elevated water tank, and the first external water source 10A supplies lubricating water to the shaft seal portion 5D and the upper bearing 5B.
It has a pipe line 10B, a valve 10C such as an electromagnetic valve or an electric ball valve and a check valve 10D provided in the first pipe line 10B, and is provided between the discharge pipe 8 and the discharge pipe 11. The intake port 10e is provided on the upstream side of the discharge valve 12
The first pipeline 10B is provided with a second pipeline 10E connected to the downstream side of the check valve 10D, and the second pipeline 10E is provided with a valve 10F such as a solenoid valve or an electric ball valve and a check valve 10G. Further, the intake port 10h is provided at a position immediately downstream of the discharge valve 12.
Is provided and has a third pipeline 10H connected to the downstream side of the check valve 10G in the second pipeline 10E.
A valve 10I such as a solenoid valve or an electric ball valve and a check valve 10J are provided in H. And the discharge valve 1
The discharge pipe 11 is raised above the position 2 and its outlet 11A is set to a position considerably higher than the discharge valve 12.

With such a configuration, when the vertical shaft pump 1 is started, the valve 10C of the first pipe line 10B in the lubricating water supply system 10 is opened, so that the shaft seal portion 5D and the upper bearing 5B are connected from the external water source 10A. The lubricating water is supplied to the intermediate bearing 5C and the lower bearing 5A through the protective pipe 13. On the other hand, when pumping is started by activating the vertical shaft pump 1, the valve 10F of the second pipe line 10E is opened, so that pumped water (self-pressurized water) in the discharge pipe 8 is discharged from the intake port 10e to the second pipe. Taken into line 10E, the first line 10B
Is supplied to the shaft seal portion 5D and the upper bearing 5B, and further supplied to the intermediate bearing 5C and the lower bearing 5A through the inside of the protective tube 13 to lubricate and cool them. In addition, the state where the self-pressurized water is flowing through the second pipeline 10E is confirmed by a flow relay (not shown),
After the confirmation, the valve 10C of the first conduit 10B is controlled to be closed.

On the other hand, when the operation of the vertical pump 1 is stopped by stopping the prime mover 9 and closing the discharge valve 12, the water in the discharge pipe 8 falls into the suction well 6 and The intake port 10e of the second conduit 10E opens at the negative pressure portion of the above, and the intake of the lubricating water from this is blocked. However, since water remains inside the discharge pipe 11,
Since the intake port 10h of the third pipeline 10H is opened in the high pressure part of the, the residual water is taken into the third pipeline 10H from the intake port 10h, and the remaining water is taken from the third pipeline 10H to the second pipeline. It is supplied to the shaft sealing portion 5D and the upper bearing 5B through 10E, and further supplied to the intermediate bearing 5C and the lower bearing 5A through the inside of the protective tube 13 to lubricate and cool them. Therefore, when the water in the discharge pipe 8 falls into the suction well 6,
Even if the impeller 3 and the main shaft 2 are reversed at high speed, the lower bearing 5A, the upper bearing 5B, the intermediate bearing 5C, and the shaft sealing portion 5
It is possible to reliably prevent the sliding portion 5 of the main shaft such as D from burning.

The lubricating water supply method described in claim 1 can be applied not only to the vertical shaft pump 1 described in the embodiment but also to other pumps. Further, although the description has been made using the valves 10F and 10I which are electromagnetic valves or electric ball valves, these may be manual valves. Further, the external water source 10A of the lubricating water supply system 10 is not limited to the elevated water tank, but may be a lubricating water supply pipe.

[0015]

As described above, according to the first aspect of the present invention, since water remains inside the discharge pipe even after the pump with the discharge valve closed is stopped, it is possible to collect water in the vicinity of the discharge valve downstream. Lubricating water can be taken from the inlet and supplied to the sliding part of the spindle. Therefore, it is possible to reliably prevent the sliding portion of the main shaft from being burned out even if the pump is reversed at a high speed due to the water in the discharge pipe dropping into the suction well. Claim 2
According to the invention, since the water remains inside the discharge pipe even after the vertical shaft pump with the discharge valve closed is stopped, the lubricating water is taken in from the intake port near the downstream side of the discharge valve and the main shaft slides. Can be supplied to the department. Therefore, it is possible to reliably prevent the sliding portion of the main shaft from burning due to the water in the discharge pipe dropping into the suction well even if the vertical shaft pump is reversed at high speed.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a vertical shaft pump to which an embodiment of the present invention is applied.

FIG. 2 is a schematic configuration diagram of a conventional vertical shaft pump.

[Explanation of symbols]

 1 Vertical shaft pump (pump) 5 Sliding part of main shaft 8 Discharge pipe 10 Lubricating water supply system 10e Lubricating water intake on the upstream side of discharge valve 10h Lubricating water intake near the downstream of discharge valve 11 Discharge pipe 12 Discharge valve

Claims (2)

[Claims] 1. A pump in which a discharge valve is provided between a discharge pipe and a discharge pipe, and the discharge pipe is raised above the position of the discharge valve, the intake of a lubricating water supply system of the pump. Ports are provided at both upstream and downstream positions of the discharge valve, and during pumping operation of the pump, lubricating water is taken in from the intake port on the upstream side of the discharge valve and supplied to the sliding part of the main shaft. When the pump is stopped in the valve closed state, the lubricating water is supplied from the intake port near the downstream side of the discharge valve and supplied to the sliding portion of the main shaft. 2. A vertical axis pump in which a discharge valve is provided between a discharge pipe and a discharge pipe, and the discharge pipe is raised above a position of the discharge valve, in an upstream side and a downstream side of the discharge valve. A vertical shaft pump having intake ports of a lubricating water supply system for supplying lubricating water to a sliding portion of a main shaft at both positions near the side.