JPH0739839B2 - Submerged pump with seating detector - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an improvement of a submerged type pump for liquefied gas, and more particularly to a pumping column comprising a handling liquid outlet cylindrical conduit inserted and arranged in a liquefied gas storage tank. (Hereafter referred to as a column)
The present invention relates to a submerged type pump provided with a seating detection device that detects a state in which a submerged type pump that is hung down inside is properly seated on the inner bottom of the column.

[Conventional technology]

Generally, various submerged type pumps are known as pumps used for discharging liquefied gas and the like in a storage tank. This kind of submerged pump is
As shown in the figure, when pumping a flammable liquefied gas from the storage tank 10, a pumping column 12 for leading out the handling liquid is dripped into the storage tank from the upper part of the storage tank 10 and introduced into this column 12. The submerged type pump 14 is suspended by a wire 19 wound around a hoist 18 and installed at the bottom of the column 12. In order to supply electric power for driving the submerged type pump 14, a conductive cable 15 having excellent insulation from the outside is stored in the column 12, and one end of this cable 15 is connected to a motor power supply terminal and the other end is connected. It is internally connected to a terminal box 16 provided outside the upper end of the column 12. Therefore, a cable for connecting to a power source is appropriately connected to the terminal box 16.

However, this submerged type pump 14 needs to be lifted via a wire 19 by a hoisting machine 18 such as a winch or hoist for repair, inspection, etc. of the pump.
After inspection, it must be hung again and installed at the bottom of column 12.

FIG. 4 shows a typical essential structure of this type of submerged pump 14. In FIG. 4, the submerged type pump is composed of a pump unit 20 and a motor unit 22, and the pump unit 20 is provided below the motor unit 22 and has a plurality of stages (two stages in the illustrated example) that are vertically communicated with each other. It has a pump chamber 24. Further, each pump chamber 24 is provided with an impeller 26, the lowermost pump chamber communicates with the suction port 28, and the uppermost pump chamber communicates with the discharge port 30. In addition, each of the impellers 26 has a rotor shaft 32 provided in a motor unit 22 described later.
Mounted on the extension shafts of. On the other hand, the motor unit 22 includes a stator assembly 34 and a rotor assembly 36, and the rotor shaft 32 is supported by an upper bearing 38 and a lower bearing 40, respectively. The pump section 20 and the motor section 22 are covered with a casing including a pump casing 42 and a motor housing 44, respectively. Motor housing
The upper part of 44 is closed with end bell 46, and this end bell 46
Inside is an upper bearing housing that supports the upper bearing 38.
48 are provided. At the lower end of the pump casing 42,
A suction manifold 50 is installed. The suction manifold 50 has a substantially cylindrical shape, and has flanges 52 and 54 at the upper end and the lower end, respectively. The upper end flange 52 of the suction manifold 50 forms an engaging portion 56 by forming its outer peripheral surface in a tapered shape, and has a tapered shape formed in an upper inner peripheral surface of a foot valve adapter 58 provided at the bottom of the column 12. It is configured to abut and lock with the seat portion 60. Also,
The lower end flange 54 of the suction manifold 50 abuts a foot valve 62 formed in the lower part of the foot valve adapter 58, and the foot valve 62 is pushed down against the elasticity of the spring 64 to open the suction port 28. To The foot valve adapter 58 is used for the column 12
It is attached to the bottom of the base by fasteners 66 such as bolts and nuts.

The submerged pump constructed in this way is
When installed in the bottom of the column 12, the tapered locking portion 56 formed in the bottom of the pump casing 42 is seated closely to the tapered seat portion 60 formed in the bottom of the column 12,
As a result, the suction port 28 side and the discharge port 30 side of the pump unit 20 are shut off in the column 12. Therefore, by starting the motor unit 22, the impeller 26 of the pump unit 20 rotates, and the liquefied gas that is the liquid to be handled in the storage tank 10 is stored in the column.
It is sucked into the pump chamber 24 from the foot valve 62 provided at the bottom of the pump 12 through the suction port 28 of the pump unit 20. The handling liquid sucked into the pump chamber 24 is compressed inside the pump chamber 24 and is discharged from the discharge port 30 into the column 12 in a high pressure state.
The handling liquid discharged into the column 12 gradually fills the column 12 and its level rises to fill the storage tank 10.
Is sent to the outside.

[Problems to be Solved by the Invention]

As described above, in the conventional submerged pump, the tapered seat portion 60 formed on the upper inner peripheral surface of the foot valve adapter 58 provided at the bottom of the pumping column 12 has the upper end flange 52 of the suction manifold 50. It is important that the tapered locking portion 56 formed on the outer peripheral surface of the seat is seated, and the locking portion 56 and the seat portion 60 are in close contact with each other. At this time, if the tapered seat portion 60 and the tapered locking portion 56 are not in intimate contact with each other over the entire circumference, the seat portion 60 and the locking portion during the liquid feeding.
Part of the handled liquid pumped from the gap with 56 is the suction port
Backflow to the 28 side and the liquid transfer efficiency decreases.

However, in the conventional submerged type pump, when it is installed in the bottom part of the column, there is no means for detecting that it is in the proper seating state as described above, and therefore the improper seating If the pump is operated in this state, not only the liquid transfer efficiency will decrease, but also abnormal vibration will occur or the seat will be partially displaced due to excessively displaced seating, which will damage the seat surface, resulting in liquid transfer efficiency. There are many problems such as further lowering

Therefore, an object of the present invention is, in a submerged type pump installed at the bottom of a pumping column, the engaging portion of the suction port of the pump detects an appropriate seating state with respect to a seat provided at the bottom of the column. It is possible to manufacture this at a low cost with a simple structure which is capable of easily detecting this state outside the tank by preventing the abnormal vibration from occurring and preventing the decrease in liquid transfer efficiency. A submerged pump having a seating detection device is provided.

[Means for Solving the Problems]

The submerged type pump provided with the seating detection device according to the present invention has a tapered locking portion of the suction manifold of the submerged type pump with respect to the seat portion formed in the foot valve adapter that constitutes the foot valve provided at the bottom of the pumping column. In the submerged type pump configured to allow the liquid to be discharged from the storage tank by seating on the seat, one or more sensor mounting holes that are opened vertically downward are formed in the tapered locking portion of the suction manifold. ,
A seating sensor having an actuator slightly projecting downward from the opening is housed in each sensor mounting hole, and is suitable as a circuit configuration for generating a predetermined output signal when all of the seating sensors perform a seating detection operation. It is characterized in that a seating detection device for determining a different sitting state is provided.

In the submerged type pump including the seating detection device, the seating sensor may be configured to operate an electric contact by a mechanical displacement of an actuator to transmit an electric signal. Further, in order to properly determine the seating state, it is preferable to connect all seating sensors in series or set as a circuit configuration for obtaining an AND condition of the operating states of all seating sensors.

[Action]

According to the submerged type pump provided with the seating detection device according to the present invention, when the foot valve provided at the bottom of the pumping column is brought into contact with the suction manifold of the submerged type pump to open the foot valve, the foot valve adapter is provided. The proper seating state of the tapered engagement portion of the submerged pump with respect to the seat portion can be detected simply and reliably by one or more seating sensors provided in the tapered engagement portion of the suction manifold. In this case, the proper seating state is determined by the circuit by the electric control system or the fluid pressure control system that generates a predetermined output signal when all the seating sensors installed are seated. The determination can be easily performed outside the tank, and as a result, the installation work of the submerged type pump on the inner bottom of the pumping column can be facilitated.

〔Example〕

Next, an embodiment of a submerged type pump including a seating detection device according to the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows an embodiment of a seating detection device according to the present invention, and is a cross-sectional view of essential parts when applied to a submerged type pump. The entire structure of the submerged type pump and its attached state are as shown in FIGS. 4 and 5, and therefore the description thereof is omitted in this embodiment. FIG. 1 is an enlarged view of an essential part showing a contact portion between a suction manifold 50 provided at a lower end portion of the submerged type pump 14 of the present invention and a foot valve adapter 58 provided at a bottom portion of the column 12. According to the present embodiment, in the tapered locking portion 56 of the upper end flange 52 of the suction manifold 50 provided at the lower end of the pump, a sensor mounting hole 68 that opens vertically downward is provided at a substantially middle portion thereof. The seating sensor 70 is housed in the sensor mounting hole 68. In this case, the seating sensor 70 is provided with an actuator 72 configured to project slightly outward from the opening portion of the sensor mounting hole 68. As a result, when the locking portion 56 of the suction manifold 50 abuts the tapered seat portion 60 of the foot valve adapter 58 provided in the bottom portion of the column 12 in an appropriate state as shown, the actuator 72 of the actuator 72 The tip also comes into contact with the tapered seat portion 60 and retracts,
The seating sensor 70 is switched.

However, in the present invention, it is required that the entire circumference of the tapered locking portion 56 of the suction manifold 50 properly abuts and sits on the tapered seat portion 60 of the foot valve adapter 58. As shown in Fig. 2, three seating sensors 70a, 70b, 70c are arranged at equal intervals, and when all of these seating sensors 70a, 70b, 70c switch operation as described above, it is determined that the seating state is proper. To configure. Therefore, as a means for making such a determination, as shown in FIG. 3, the seating sensors 70a, 70b, 70c are connected in series to establish a proper seating state when a predetermined loop current is obtained. It can be configured to distinguish and display
It is possible to configure a logic circuit that obtains an AND condition for each of the switching operations of 70a, 70b, and 70c, and to determine and display an appropriate seating state when the AND condition is satisfied. When configuring such a discrimination display circuit, the conductive wire 7 derived from each seating sensor 70a, 70b, 70c is used.
4 can be appropriately taken out of the pump casing, guided upward in the column 12, and integrated with the conductive cable 15 of the submerged type pump to be connected to the terminal box 16 for external connection.

In this way, the state in which the submerged pump 14 is properly seated and installed on the bottom of the column 12 can be easily determined outside the tank.

Incidentally, in the above-mentioned embodiment, as the seating sensor 70,
Although the mechanical displacement is configured to operate as an electrical contact, the mechanical displacement of other actuators is taken out of the tank as a pressure fluctuation of gas or liquid using a required transmission system, and each seating sensor 70 It is also possible to configure so as to distinguish and display the operating state of.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, but is within a range not departing from the spirit of the present invention, such as the mounting configuration of the seating sensor and the number of the seat sensors used. It goes without saying that various design changes can be made in.

〔The invention's effect〕

As is apparent from the above-mentioned embodiments, according to the present invention,
At the lower end of the submerged pump, when installing the submerged pump so as to contact and open the foot valve provided at the bottom of the pumping column, the tapered locking portion of the suction manifold and the foot valve adapter are installed. A proper seating state with the tapered seat portion can be detected simply and reliably by a plurality of seating sensors provided on the tapered locking portion. In this case, even when the detection signal is taken out, it can be easily designed by utilizing the space in the cylindrical conduit.

In particular, in the present invention, when all the installed seating sensors are configured to perform a seating detection operation, a circuit including an electric control system or a fluid pressure control system that generates a predetermined output signal is used to ensure a proper seating state. The determination can be easily performed outside the tank, and as a result, the installation work of the submerged type pump on the inner bottom of the pumping column can be facilitated.

Therefore, since the proper seating state of the submerged type pump can be easily confirmed outside the tank in this way, the installation work of the submerged type pump is facilitated, and the liquid transfer efficiency during pump operation is reduced. There are many advantages such as preventing abnormal vibrations, preventing damage to the seating portion of the pump, and simplifying maintenance work.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part showing an embodiment of a submerged type pump provided with a seating detection device according to the present invention, and FIG.
FIG. 3 is an explanatory view showing an arrangement state of the seating sensor shown in FIG. 3, FIG. 3 is an electric circuit diagram of a seating detection device, FIG. 4 is a sectional view showing a main structure of a submerged pump according to the present invention, and FIG. It is a schematic explanatory drawing which shows the installation state of a type | mold pump. 10 …… Storage tank 12 …… Cylindrical conduit (column) 14 …… Submerged pump 15 …… Conductive cable 16 …… Terminal box 18 …… Hoisting machine 19 …… Wire 20 …… Pump section 22 …… Motor section 24 …… Pump chamber 26 …… Impeller 28 …… Suction port 30 …… Discharge port 32 …… Rotor shaft 34 …… Stator assembly 36 …… Rotor assembly 38 …… Top bearing 40 …… Bottom bearing 42 …… Pump casing 44… … Motor housing 46 …… End bell 48 …… Upper bearing housing 50 …… Suction manifold 52,54 …… Flange 56 …… Locking part 58 …… Foot valve adapter 60 …… Seat part 62 …… Foot valve 64 …… Spring 66 ...... Fastener 68 …… Sensor mounting hole 70 …… Seating sensor 72 …… Actuator 74 …… Conductive wire

Claims (3)

[Claims] Claim: What is claimed is: 1. A seat formed on a foot valve adapter that constitutes a foot valve provided at the bottom of a pumping column,
In a submerged pump configured to seat a tapered engagement portion of a suction manifold of a submerged type pump to discharge a liquid to be handled in a storage tank, the tapered engagement portion of the suction manifold is vertically downwardly opened. Drill one or more sensor mounting holes,
A seating sensor having an actuator slightly projecting downward from the opening is housed in each sensor mounting hole, and is suitable as a circuit configuration for generating a predetermined output signal when all of the seating sensors perform a seating detection operation. A submerged pump provided with a seating detection device, which is provided with a seating detection device for determining various seating states. 2. A submerged type pump having a seating detection device according to claim 1, wherein the seating sensor is configured to operate an electric contact by a mechanical displacement of an actuator to transmit an electric signal. 3. The seating sensors are connected in series, or the circuit configuration for obtaining the AND condition of the operating states of all the seating sensors is set so as to properly determine the seating state. A submerged pump including the seating detection device according to Item 1.