JPS5838398A - Pump apparatus - Google Patents

Abstract

PURPOSE:To enable to supply fluid with an increased pump head or flow rate as the case demands, by employing a combination of a first valve means interposed between the suction side of one pump and the discharge side of another pump and a second valve means interposed between the first valve means and a place to which the fluid is to be supplied. CONSTITUTION:When the reactor pressure is lowered through condensation of steam in a pressure vessel 2 of a nuclear reactor while supplying cooling water to the pressure vessel 2 under a high pump head through series operation of a plurality of pumps arranged in two systems, globe valves 20, 23 constituting a first ON-OFF valve means are closed while globe valves 21, 22 constituting a second ON-OFF valve means are opened as shown in the drawing. Resultantly, pumps 5, 6 and pumps 7, 8 that have been operated respectively in series to each other are all operated independently from each other, so that an extremely large amount of cooling water can be supplied to the pressure vessel 2 of the nuclear reactor from a condensate storing tank 4 or a suppression pool 3 having four independent water supply sources. By employing such an arrangement, it is enabled to eliminate additional equipment such as high-pressure reactor core spray pumps that have been required in the conventional arrangements.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pump device that can selectively increase head or flow rate.

For example, boiling water nuclear reactors are equipped with emergency core cooling equipment in case of a coolant spill accident due to a rupture in the reactor system piping. This emergency core cooling equipment consists of a plurality of independently operating pump devices, etc., as shown in FIG. 1 is a reactor containment vessel, and a reactor pressure vessel 2 is installed in the upper part of the reactor containment vessel 1, and has a reactor core (not shown) made up of a large number of fuel assemblies inside. are doing. The pressure vessel 2 serves as a common supply part for the plurality of pump devices, and a sabre and John pool 3 is provided in the lower part of the reactor containment vessel 1 and is filled with cooling water. . This suppression sol 3
serves as a common fluid supply source for the plurality of pump devices. As a fluid supply source, this sacilage,
In addition to the tank 3, a condensate storage tank 4 provided outside the reactor containment vessel 1 is used. However, from this condensate storage tank 4, cooling water is supplied only to a high-pressure spray pump 9, which will be described later. As the above-mentioned pump device, the above-mentioned high pressure core Sgray pump 9
There are three types: one that includes a low-pressure core spray range 5, and one that includes a low-pressure injection I-ring 6° 7.8 tl, and each pump device has an independent piping system and a common supply part. Cooling water is supplied into the reactor pressure vessel 2. Further, the pump device including the high pressure core spray range 9 and the pump device including the low pressure core spray range 5 have a core spray jar 14 at the end of each pipe. This core spray/9
- The reactor is installed above the reactor core (not shown) in the reactor pressure vessel 2, so that cooling water can be directly injected into the reactor core. Furthermore, a plurality of automatic relief valves 15 (only one is shown) are connected to the main steam pipe 13 that transfers steam from the reactor pressure vessel 2 to the turbine. These relief valves 15 also constitute a component of the emergency core cooling equipment together with the plurality of pump devices. In the event of a coolant spill accident, this automatic relief valve 15 is configured to
It functions as a backup system for pump 9. In other words, the plurality of automatic relief valves 15 are opened at different times to release steam in the reactor pressure vessel 2, thereby lowering the reactor pressure. In addition, the low pressure spray range 5, the low pressure injection pump 'f6, the low pressure injection pump 17°7, the low pressure injection inlet 8, and the high pressure core spray range 9 are driven by common emergency diesel generators 1θ, 11°12, respectively. It is said that

In the emergency core cooling equipment configured as described above, for example, a coolant leakage accident due to a small or medium rupture accident causes the pressure inside the reactor pressure vessel 2 to rise, and the pressure inside the reactor pressure vessel 2 increases. Suppose that the coolant water level has dropped to a certain critical level. The high-pressure core spray pump 9 starts immediately and supplies cooling water from the fluid supply source Zazoreshi, Nzor 3 or the condensate storage tank 4 into the reactor pressure vessel 2 at a high enough head to overcome the reactor pressure. The streaks are transmitted via the race part toy 14. The steam is then condensed to lower the furnace pressure. Here, if the high-pressure core spray/puffer 9 does not operate for some reason, the required number of automatic relief valves 15 are opened, and the reactor pressure vessel 2
The steam inside the reactor pressure vessel 2 is released to the reactor pressure vessel 3 to reduce the pressure inside the reactor pressure vessel 2. When the reactor pressure is lowered, in addition to the high-pressure core injection pump 9, the other low-pressure injection pumps e and 1.8 and the low-pressure core injection pump 5 also operate to pump out a large flow of cooling water. Supplied into the reactor pressure vessel 2. At this time, since the pressure inside the reactor pressure vessel 2 has decreased, it becomes possible to supply cooling water even with a low-pressure system pump.

However, the conventional emergency core cooling equipment as described above does not have a single high-pressure core spray system (9) to protect against coolant spill accidents caused by small or medium-sized fractures, and if one system fails for some reason, automatic relief is provided. The valve 15 must be used to release the steam in the reactor pressure vessel 2 and lower the reactor pressure. In addition, since the high-pressure core spray range 9 requires a high head, it is only possible to use an extremely large multi-stage vertical electric volute pump, but this multi-stage vertical electric volute pump is extremely expensive. It is also large in size, which is not desirable in terms of earthquake-resistant design, and it also poses great difficulties in installation work and maintenance.

Figure 2 shows the status of the installation work. There is an opening 1 in the ceiling of the floor where the multi-stage vertical electric swirl pump f9 as the high-pressure core spray range is installed.
There is an electric hoist 17 for lifting on the ceiling of the upper floor. The multi-stage vertical electric centrifugal pump 9 is
The electric hoist 17 carries the product from the upper floor through the opening 16 to the floor below. Then, a bit 19 must be provided on the mat 18 of the floor, and the casing portion of the multistage vertical electric centrifugal pump 9 must be embedded therein. These operations are extremely difficult and dangerous, and place a heavy burden on the construction work, civil engineering, and construction work. Further, the emergency diesel generator 12 and other auxiliary equipment are also large-scale, and when these auxiliary equipment are included, an extremely large installation area is required. And this high pressure core Ssolley Bomb 9 equipment,
Furthermore, cooling equipment for cooling and removing heat from the equipment itself is required, and these cooling equipment also have the disadvantage of being extremely expensive.

The present invention has been made in view of the above points, and its purpose is to reduce the cost of the entire device by eliminating the need for a large pump, and to improve the safety of the seismic design. It reduces the burden on civil engineering and construction, makes it possible to selectively supply high head or large flow fluids with small-scale equipment, and can be used as a backup if it is compatible with the emergency core cooling equipment of boiling water reactors. It is an object of the present invention to provide a pump device that can use small-scale auxiliary equipment such as a diesel generator as a power source, and also facilitates installation work and maintenance.

That is, in the pump device according to the present invention, a pump is inserted into each of a plurality of independent supply pipes for selectively supplying fluid at a high head or a large flow rate from a fluid supply source to a common supplied part, and different pumps are connected to each other. A first on-off valve is inserted between the suction side and the discharge side, a second on-off valve is inserted between the first on-off valve and the supplied part, and the first on-off valve and the supplied part are interposed between the first on-off valve and the supplied part. A check valve is inserted between the reactor pressure vessel 2 and the first on-off valve to open when the pressure inside the reactor pressure vessel 2 is high and close when the pressure is low, and conversely, the second on-off valve is opened when the pressure inside the reactor pressure vessel 2 is low. It is constructed by interlocking so that the valve is open and the pressure cylinder is closed.

By configuring as above, the first and second
The number of pumps can be operated in series or independently by opening and closing the on-off valves, and either the head or the flow rate can be selectively increased as required. This makes it possible to eliminate the need for large pumps and downsize or reduce the size of ancillary equipment, thereby reducing the installation space, making construction and maintenance easier, and ultimately reducing the cost and improving the safety of the entire device. It is something that can be done.

Embodiments of the present invention will be described below with reference to FIGS. 3, 4, and 5. Note that the same parts as in FIG. 1 will be described with the same reference numerals.

In Fig. 3, 1 is a reactor containment vessel, and in the upper part of the reactor pressure vessel 1, a reactor pressure vessel 2 is installed as a part to which fluid is supplied, and is composed of a large number of fuel assemblies. It has an internal reactor core (not shown). At the bottom of the reactor containment vessel 1, there is a sagre, a simple pool 3.
is installed and filled with cooling water. This Sadere?
The /1 pump 3, together with a condensate storage tank 4 installed outside the reactor containment vessel l, serves as a fluid supply source for a plurality of pump devices. In addition, the above-mentioned plurality of delf devices include a pump device including the low-pressure core Szoray I ring 5 and a pump device including the low-pressure injection pump 6.7.8.The flow rate-head characteristic of each pump is the curve 26 in FIG.
This is shown in . And the above four pumps 5, 6, 7
．． 8 has independent piping 26, 27, 28, 29 between the fluid supply source and the supplied part, and at the same time, there is a first opening/closing pipe between the suction side of the pump 5 and the discharge side of the pump 6. A globe valve 20, which is a valve, is connected, and a globe valve 21, which is a second opening/closing valve, is inserted between the globe valve 20 and the reactor pressure vessel 2, which is a part to which fluid is supplied. A check valve 21 is inserted in the pipe 26 between the globe valve 20 and the fluid supply source. Similarly, a first on-off valve is connected to the suction side of the pump 8 and the discharge side of the pump f7. It is connected by piping having a globe valve 23,
A globe valve 22, which is a second on-off valve, is inserted between the globe valve 23 and the reactor pressure vessel 2, which is a fluid supplied part.

A check valve 25 is inserted into the piping 29 between the on-off valve 23 and the fluid supplied portion. Between the globe valves 20 and 21 and between 23 and 22, when the globe valve 20 is open, the globe valve 2 is closed, and conversely, when the globe valve 20 is closed, the globe valve 2 is open. It looks like the interface has been removed. And 23 and 22 are similarly interlocked. 2. Independent piping for pumps 5 and 8. The core Sugereno Cooler 14 is connected to the terminal ends of \61 and 27. The operation of this embodiment, in which the automatic relief valve 15 is connected to the main steam pipe 13, will now be described. Assume that a rupture accident occurs in the reactor pressure vessel 2, the cooling water in the reactor pressure vessel 2 flows out, and the pressure rises. Pump 5,6°1.8 starts immediately. At that time, the first on-off valve, the globe valve 20.23, is opened, and the second on-off valve, the second on-off valve, is opened. Valves 21,22 are closed. Tsuma Shiponzo 6,5
The pumps 1.8 and 1.8 are operated in series via on-off valves 20 and 2B, respectively.The flow rate-head characteristic at this time is shown by the curve 21 in FIG. Then, the cooling water from the subledge and pool 3, which is the supply source, is supplied into the reactor pressure vessel 2, which is the supplied part, at a high enough pressure to overcome the pressure inside the reactor, and the cooling water is passed through the core streak purger 14 to cause slag. , condenses the steam in the reactor pressure vessel 2 and lowers the reactor pressure. At this time, the check valves 24 and 25 function to prevent backflow. In this case, the interfaces 5゜6 and 7,8
The devices that correspond to the conventional high-pressure core Sugerei 4 and 9 will each play the role of the conventional high-pressure core Sugerei 4 and 9.
This means that a system has been established. Therefore, even if one of the systems does not operate for some reason, the other system can perform the same function as the conventional high-pressure spray pump 9.

As described above, high-head cooling water is supplied into the reactor pressure vessel 2 by the two series-operated four-bar systems, and when the steam condenses in the reactor pressure vessel 2 and the reactor pressure decreases, as shown in Fig. 4. As shown in FIG.
Open the valve.

Therefore, pumps 5 and 6 and pumps 2 and 8, which have been operated in series up to now, operate independently, and the overall flow head-lift characteristic becomes as shown by curve 28 in FIG. 5. And there is a subledge, which is a supply abyss with four independent systems.

A very large amount of cooling water is supplied from the reactor pressure vessel 2, which is the supplied part, from the reactor tank 3 or the condensate storage tank 4.

As described above, when the configuration of the above embodiment is adopted, the first on-off valve 2
By opening the valves 0.23 and closing the second on-off valves 21 and 22, the pumps 5 and 6 and pumps II are operated in series, supplying high-head cooling water into the reactor pressure vessel 2. This makes it possible to eliminate the conventionally installed high-pressure core sedge pump 9, diesel generator 12 serving as its driving source, and other incidental equipment.

Furthermore, since two systems of equipment corresponding to the high-pressure Sgreipong 9 can be obtained, the safety of the equipment is improved. Then, by closing the first on-off valve 20.23 and opening the second on-off valve 11.22, each of the four systems can be operated independently, and a large flow of fluid is transferred to the reactor pressure vessel 2. can be supplied within

In this embodiment, a case has been described in which four I pumps are used to form a set of two pumps, but a single device may be configured including all the pumps used. That is, FIG. 6 shows an example in which four pumps 33, 34, 35, and 36 are all incorporated into a single device, and the suction side of pump 33 and the discharge side of pump 34 are connected to the first They are connected by a pipe having a globe valve 37, which is an on-off valve, and a globe valve 40, which is a second on-off valve, is inserted between the globe valve 37 and the supplied object 846. Further, a check valve 43 is inserted in a pipe 48 between the globe valve 37 and the fluid supply source 4r. Similarly, Bonn f34 and Inf
315, there is a globe valve JJ1 which is the first on-off valve.
A globe valve 41 serving as a second on-off valve is inserted between the globe valve 38 and the supplied portion 460, and a check valve 40 is inserted in a pipe 49 between the globe valve 38 and the fluid supply source 42. .

Also, between the fourth ring 35 and the pump 36, there is a globe valve 39, which is a first on-off valve, and the globe valve 39 and the supplied part 46.
Between the globe valve 39 and the fluid supply source 47, there is a check valve 4 in the piping 50.
5 are inserted respectively.

According to the above configuration, for example, the first on-off valve 37,
38. 39 is opened and the on-off valve 40, which is the second on-off valve,
If valves 41 and 42 are closed, the four pumps 33, 34, and 35
．． 36 is operated in series, and fluid at a higher level than in the previous embodiment can be supplied from the supply source 41 to the supplied portion 46. Conversely, if the first on-off valve 37, 38, 39 is closed and the second on-off valve 40, 41.42 is opened, the four pumps 33, 34, 35, 36 can be operated independently. As a result, a large flow of fluid can be supplied from the fluid supply source 47 to the supplied portion 46 as in the previous embodiment.

Further, all the on-off valves can be opened or closed in sequence. For example, the first on-off valves 3r and 39 are opened, and the on-off valve 38 is closed. and a second on-off valve 40
．． 42 is closed and on-off valve 41 is opened. At this time Bon 7'? 4 and 33 and? The two pumps 36 and 35 are operated in series, and the supply source 47 is connected to the supplied part 46 in two systems.
Fluid will be supplied to.

In this way, the first on-off valve, the on-off valve 37.38°39
By appropriately combining the opening and closing of the on-off valves 40, 41 and 42, which are the second on-off valves, various combinations of head and flow rate can be changed. However, the corresponding first and second on-off valves, for example on-off valve 37 and on-off valve 40, are not opened or closed at the same time,
It is assumed that the valve is interlocked so that when one valve is open, the other valve is closed.

As detailed above, according to the pump device of the present invention, a pump is inserted in each of a plurality of independent supply pipes that selectively supply high head or large flow fluid from a fluid supply source to a common supplied part. , a first on-off valve is inserted between the suction side and the discharge side of the different pumps, a second on-off valve is inserted between the first on-off valve and the supplied part, and the first on-off valve is inserted between the first on-off valve and the supplied part. A check valve is inserted between the first on-off valve and the fluid supply source, and the head or at each can be adjusted as necessary by the combination of opening and closing of the first on-off valve and the second on-off valve. It is possible to supply expensive fluid from a fluid supply source to a supplied part. This makes it possible to eliminate the need for large pumps and downsize or reduce the size of ancillary equipment, thereby reducing equipment installation space, facilitating construction and maintenance, and ultimately reducing costs and improving safety of the entire equipment. It is something.

[Brief explanation of the drawing]

Fig. 1 is a system diagram showing a conventional example of emergency core cooling equipment for a boiling water reactor, Fig. 2 is a schematic front view showing the installation status of a high-pressure core spray pump, and Figs. 3 to 5 are in accordance with the present invention. 3 and 4 are system diagrams,
FIG. 5 is a diagram showing flow rate-head characteristics, and FIG. 6 is a system diagram showing another embodiment of the present invention. 2... Reactor pressure vessel (supplied part) 3... Suppression sol (fluid supply source 'A4... Condensate storage tank (fluid supply source), 5... Low pressure core spray pump, 6
．． 7.8...Low pressure injection pump, 20.23...Globe valve (first on-off valve'), 21.2:z...Globe valve (second on-off valve), 24.25... ·non-return valve. Applicant's agent Patent attorney Takehiko Suzue, Figure 5 500 1000 500 2000 2
500-11 →-button t (m”/h) No. 6111 Mu6

Claims (2)

[Claims] (1) A plurality of independent supply pipes that selectively supply fluid at a high flow rate to a common supplied part from a fluid supply source to a high-head or large-flow shelter, and a plurality of supply pipes inserted in each of these pipes. a first on-off valve inserted between the pump and the suction side and a discharge side of different tanks; and a second on-off valve inserted between each of the first on-off valves and the supplied portion. A pump device comprising: an on-off valve; and a check valve inserted between each of the first on-off valves and a fluid supply source. (2) The pump device according to claim 1, in which the number of 4/g units is an even number, and each set includes two units.