JPS63246497A - Pump shaft sealing device - Google Patents

Abstract

PURPOSE:To prevent the generation of fault due to sedimentation of a solid matter, by suitably opening an automatic closing valve by a control device and discharging the solid matter sedimented upstream of a flow controller. CONSTITUTION:In the case that sand in the sea water is sedimented upstream of a flow limiting orifice 11 during normal operation, a flow of drain passing through the flow limiting orifice 11 is reduced by such sedimentation of the sand. When the flow becomes not greater than a predetermined value, a flow switch 103 is operated. An output from the flow switch 103 is fed to a solenoid valve 101 to open the same. As a result, the sand sedimented upstream of the flow limiting orifice 11 is discharged through a sand discharging line 12. When a predetermined time is elapsed, a timer 105 is operated to close the solenoid valve 101. The above operation is similarly repeated to thereby automatically discharge the sand sedimented upstream of the flow limiting orifice 11.

Description

[Detailed Description of the Invention] [Purpose of the Invention (Field of Industrial Application) The present invention relates to a seawater pump, etc. that supplies seawater as cooling water to a heat exchanger in an auxiliary cooling system of a thermal power plant or a nuclear power plant, for example. This invention relates to a shaft sealing device for a pump.

(Prior Art) For example, as a shaft sealing device for a seawater pump, it is common to self-supply lubricating water from the seawater pump, remove foreign matter with a strainer, cyclone separator, etc., and then use it as lubricating water for the bearing. However, in special cases, fresh water may be supplied as circulating water from other facilities.

Therefore, the configuration of a self-contained seawater pump shaft sealing device will be explained with reference to FIG. Reference numeral 1 in the figure is a seawater pump, and this seawater pump 1 has its pump part 2 immersed in seawater 3.
Further, an electric motor 4 connected to the pump section 2 is provided outside the seawater 3. A lubricating water supply pipe 6 is branched from the discharge pipe 5 of the seawater pump 1, and a portion of the seawater is supplied to the bearing 7 as lubricating water via the lubricating water supply pipe 6. A strainer 8 and a cyclone separator 9 are sequentially inserted into the lubricating water supply pipe 6. The strainer 8 removes shells, seaweed, etc. from the seawater, and the cyclone separator 9 removes sand contained in the seawater. The sand removed by the cyclone separator 9 is continuously returned to the seawater 2 via the drain line 10. A flow rate limiting orifice 11 is inserted into the drain line 10 to maintain a constant drainage flow rate. A sand discharge line 12 is branched and connected to the upstream side of the flow rate restriction orifice 11, and an on-off valve 13 is inserted in this sand discharge line 12. That is, sand may accumulate on the upstream side of the flow rate υ1 limit orifice 11 and cause clogging. This is especially noticeable when the sea is rough. Therefore, by appropriately opening the on-off valve 13, the sand accumulated on the upstream side of the flow rate limiting orifice 11 is discharged via the sand discharge line 12.

The above configuration has the following problems. In other words, the sand accumulated on the upstream side of the flow restriction orifice 11 is removed by the on-off valve 13.
As described above, the sand is removed through the sand discharge line 12 by opening the valve as appropriate by the worker. However, for example, when the sea is rough and there is a lot of exposed sand, it is necessary to perform the above operation frequently. This places a heavy burden on the workers. Furthermore, if the above operations are neglected, the drain line 10 will be clogged with sand and the cyclone separator 9 will eventually lose its function. In such a case, sand in the seawater will enter the bearing 7 and shorten the q life of the bearing 7 or reduce the tI ratio of the seawater pump 1.
It is also expected that plant operations will be disrupted.

(Problems to be solved by the invention) In this way, with the conventional configuration, the troublesome sand removal work is unavoidable, and if this work is neglected, the function of the seawater pump and even the plant itself may be affected. The present invention has been made based on these points, and its purpose is to relieve the labor of labor from the complicated sand removal work and to improve the health of the pump and, ultimately, the plant. An object of the present invention is to provide a pump shaft sealing device that can be maintained reliably.

[Structure of the Invention] (Means for Solving the Problems) That is, the pump shaft sealing device according to the present invention has a lubrication system that is branched from the discharge side of the pump and supplies a part of the discharged fluid to the bearing portion of the pump as a lubricating fluid. A fluid supply pipe, a solids removal device inserted into the lubricating fluid supply pipe to remove solids from the fluid, and a discharge pipe that discharges wastewater containing the solids removed by the solids removal device; A flow restrictor is inserted into this discharge piping to maintain a constant drainage flow rate, a solids discharge piping is branched from the upstream side of this flow restrictor and discharges solids accumulated on the upstream side of the flow restrictor, and Equipped with a control device that detects the accumulation of solids on the upstream side of the flow restrictor by controlling the opening and closing of the 11J automatic valve inserted in the distribution pipe and the automatic valve. It is also (+) that is characterized by having done something.

(Function) In other words, the solid content accumulated on the upstream side of the flow restrictor is discharged by opening the automatic on-off valve as appropriate by the control device.
This prevents problems caused by the accumulation of solids.

(Example) An example of the present invention will be described below with reference to FIG. It should be noted that the same parts as in the prior art are denoted by the same reference numerals and the explanation thereof will be omitted. A solenoid valve 101 as an automatic opening/closing valve is inserted into the sand discharge line 12.

The one-way flow restriction orifice 11 has a flow detection line 102.
A flow rate switch 103 is connected via. In addition, the outflow restriction orifice 11 also functions as a flow rate detection orifice, and when the drainage flow rate falls below a preset value due to sand accumulation, the flow rate switch 103 is activated.
Activate. Letter from flow rate switch 103 @5103
is output to the electromagnetic valve 101 via the electric circuit 104, thereby controlling the opening and closing of the electromagnetic valve 101. A timer 105 is inserted in the electric circuit 104. Moreover, the flow layer switch 103 is a flow layer switch 103.
l orifice 11, thereby preventing sand from entering into the detection line 102.

The operation will be explained based on the above configuration. Assume that sand in the seawater has accumulated on the upstream side of the flow rate limiting orifice 11 during normal operation. Due to the accumulation of sand, the amount of wastewater flowing through the flow W1 restriction orifice 11 is reduced. Then, when the flow rate becomes lower than a preset predetermined flow rate, the flow rate switch 1
03 is activated.

Due to the operation of this flow rate switch 103, a signal 5103 is output to the solenoid valve 101, and the solenoid valve 101 opens. By opening this solenoid valve 101, the flow ffi limiting orifice 11
The sand accumulated on the upstream side of the sand is discharged via the sand discharge line 12. Then, when a preset time has elapsed, the timer 105 is activated and the solenoid valve 101 is closed. The above-mentioned time is set by measuring the time required to discharge the accumulated sand in advance and referring to the time. Thereafter, by repeating the same action, the sand accumulated on the upstream side of the flow restriction orifice 11 is automatically discharged.

According to this embodiment, the following effects can be achieved.

(1) First, the sand accumulated on the upstream side of the flow rate control orifice 11 can be automatically discharged. In other words, when the amount of wastewater flowing through the flow restriction orifice 11 decreases due to the accumulation of sand, and the flow rate becomes less than the preset flow rate, the flow rate switch 103 is activated.
This is because the solenoid valve 101 is activated to open the solenoid valve 101, and this continues for a predetermined period of time until the timer 105 is activated.

Therefore, all the sand removal work that was conventionally done manually by workers is now done automatically, and the burden on the workers can be significantly reduced.

■In addition, unlike in the past, sand removal is not performed due to worker's carelessness, etc., and as a result, the cyclone separator 9 loses its start-up ability due to sand accumulation, and furthermore, the health of the seawater pump 1 and the plant is impaired. Such situations can also be definitely prevented. Also, to avoid sand build-up, drain piping 1
The need for disassembling and repairing the 0-cyclone separator 9 and the like is also reduced.

(2) Also, since the flow rate switch 103 of this embodiment is installed at a higher level than the flow rate limiting orifice 11, there is no possibility of sand being deposited in the detection line 102 or the like.

■Furthermore, the sand discharge line 12 is branched from a position upstream of the flow ω control orifice 11 and close to the flow rate restriction orifice 11.
There is no accumulation of sand between the two.

Note that the present invention is not limited to the above-mentioned actual flow example, and may be configured such that, for example, the @magnetic valve 101 is opened at certain time intervals by the action of the timer 105. Further, the automatic opening/closing valve may be other than a solenoid valve. Furthermore, it goes without saying that the present invention is not limited to seawater pumps, but can be effectively applied to other types of pumps in which solids such as sand are contained in the fluid handled.

[Effects of the Invention] As detailed above, according to the pump shaft sealing device according to the present invention, the loss of function of the solid content removal device due to solid content accumulation, and thereby the pump and eventually The effects are great, such as being able to reliably prevent situations where the health of the plant is impaired.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a pump shaft sealing device according to an embodiment of the present invention, and FIG. 2 is a configuration diagram of a pump shaft sealing device according to a conventional example. 1... Seawater pump, 6... Lubricating water supply piping, 7...
・Bearing, 9...Cyclone separator, 10...Discharge piping, '11...Hot stone restriction orifice, 12...
Sand removal 1! ii! Pipe, 101... Solenoid valve, 103...
Flow rate switch, 104... Electric circuit, 105... Timer.

Claims (3)

[Claims] (1) A lubricating fluid supply pipe that is branched from the discharge side of the pump and supplies a portion of the discharged fluid to the bearing portion of the pump as a lubricating fluid, and a lubricating fluid supply pipe that is inserted into this lubricating fluid supply pipe to remove solids from the fluid. A solids removal device, a discharge pipe for discharging wastewater containing solids removed by the solids removal device, a flow limiter inserted in the discharge pipe to maintain a constant flow rate of the wastewater, and the flow limiter. a solid content discharge pipe that is branched from the upstream side of the flow restrictor and discharges solid content accumulated on the upstream side of the flow restrictor, and an automatic on-off valve inserted in the solid content discharge pipe;
A pump shaft sealing device comprising: a control device that controls the accumulation of solids on the upstream side of the flow restrictor by controlling opening and closing of the automatic opening/closing valve. (2) The pump shaft seal according to claim 1, wherein the control device controls opening and closing of the automatic opening/closing valve by detecting the flow rate of waste water passing through the flow restrictor. Device. (3) The pump shaft sealing device according to claim 1, wherein the control device opens and closes the automatic on-off valve at predetermined intervals.