JPH11229485A - Post-attachment type pre-swirl tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve workability on installation by easily mounting a pre-swirl tank without being subject to the effect of a flood even in a flood manhole, to which groundwater, etc., leach, while inhibiting vibrations at the time of pump operation by surely fixing a holder with mortar or concete. SOLUTION: The mounting recessed sections 25A of holders are recessed downwards among a pre-swirl sections 3A and a first partition wall, and the lower-side region 24A of a sewage storage section and a lower-side region 24B in a pre-swirl-section forming region containing each periphery of pre-swirl sections 3A communicating with the lower-side region 24A and the mounting recessed sections 25A of a plurality of the holders are opened into a manhole 1. The holders 10A are set up to the mounting recessed sections 25A of the holders and mortar or concrete 18 is placed, and communicating passages communicating the lower-side region 24A of the sewage storage section and the lower-side region 24B of the pre-swirl section forming region with the pre-swirl sections 3A while being penetrated to each peripheral wall of the pre-swirl sections 3A are formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a retrofitting pre-swirl tank installed at the bottom of a manhole or the bottom of a suction water tank of a pump constructed at an appropriate place in a sewage drainage piping system connecting a sewage generation source and a sewage treatment plant. About.

[0002]

2. Description of the Related Art Conventionally, as shown in FIGS. 4 to 6, fibers such as FRP are provided at the bottom of a concrete manhole 1 constructed at an appropriate place in a sewage downflow piping system connecting a sewage generation source and a sewage treatment plant. Retrofitting pre-swirl tank 2 made of a substantially disk-shaped disk-shaped body made of reinforced plastic
Techniques for installing a pre-swirl tank are well known. The pre-swirl tank 2 includes a pair of pre-swirl units 3A and 3B.
And a pair of mounting seats 6A and 6B, a sewage storage section 7 and a partition wall section 8, and extend in the width direction at the center of the pre-swirling tank 2 in the longitudinal direction L. The first turning wall 8A of the partition wall portion 8 protruding upwardly divides the pre-swirling portion forming area 12 on one side in the longitudinal direction and the sewage storage section 7 on the other side in the longitudinal direction.

The pre-swirl units 3A, 3B are provided with pumps P1, P2
For inserting the air inlet 13 of the first partition wall 8A.
The pre-swirl portions 3A and 3B are sectioned in the width direction W and are recessed downward by a second partition wall 8B provided so as to extend to the pre-swirl portion forming area 12 side orthogonally to.

The sewage in the sewage storage unit 7 is guided to the pre-swirling unit 3A from the inflow path 4 in a tangential direction or a direction close thereto,
A pre-swirl flow is generated in the pre-swirl section 3A, which swirls in the same direction R1 as the rotation direction R of the impeller (not shown) of the pump P1. Further, the sewage in the sewage storage unit 7 is guided to the pre-swirling unit 3B from the inflow path 5 in a tangential direction or a direction close to the sewage. A pre-swirling flow that turns in the same direction R1 as the rotation direction R is generated.

The pair of mounting seats 6A and 6B are
A, 3B and the first partition wall 8A. The discharge curved pipe 9A is mounted on the mounting seat 6A, and the discharge curved pipe 9B is mounted on the mounting seat 6B. The discharge curved tube 9A mounted on the mounting seat 6A is fixed to the upper end of the gantry 10A via the mounting seat 6A, and the discharge curved tube 9B mounted on the mounting seat 6B is connected to the mounting seat 6B. And is fixed to the upper end of the gantry 10B. The discharge port of the pump P1 is connected to one end of the discharge curved pipe 9A, the lower end of the discharge pipe 11A is connected to the other end of the discharge curved pipe 9A, and the discharge pipe 9B is connected to one end of the discharge curved pipe 9B. The discharge port of the pump P2 is connected, and the lower end inlet of the discharge pipe 11B is connected to the other end of the curved discharge pipe 9B. Stand 10
The lower member 10b of each of A and 10B is fixed by anchor bolts 17 and 17 and a nut 17A erected on the bottom member 1A of the manhole 1.

The sewage storage section 7 is provided on the other side of the first partition wall 8A in the longitudinal direction L through the vertical step surface 14 over the entire area in the width direction W. The sewage storage section 7 is inclined in a downward gradient from the other end in the longitudinal direction L to the lower end of the vertical step surface 14, and communicates with the inflow water passages 4 and 5 on both sides in the width direction W of the first partition wall 8A. ing. In addition, the gantry 10A, 1
4B, four bolts 15, 15... (Only two bolts 15, 15 are shown in the drawing) are fixed through the upper member 10a from below. Therefore, each of the lower members 10b of the gantry 10A, 10B
Are fixed to the bottom member 1A of the manhole 1 with the anchor bolts 17, 17, and bolts 15, 15,... Are provided in four mounting holes 6A, 6B, respectively. Only through holes) and four through holes (only two through holes are shown in the drawing) provided in the base portion 9C of the discharge curved pipes 9A and 9B, and are projected upward. By screwing a nut 16 onto these protruding portions, the mounting base 1 is mounted via the mounting seats 6A and 6B.
0A and 10B, the pre-swirling tank 2 and the discharge curved pipes 9A and 9
B is supported.

While the pre-swirl tank 2 is supported by the gantry 10A, 10B, the pre-swirl tank 2 and the bottom member 1A of the manhole 1 are provided.
And a space 24 surrounded by the standing wall 1B of the manhole 1;
That is, the first space 24A below the sewage storage section 7 and the second space 24 formed below the pre-swirl section forming area 12 including the periphery of the pre-swirl sections 3A and 3B and communicating with the first space 24A.
B, mortar or concrete 18 is cast from a gap between the outer circumference of the pre-swirling tank 2 and the inner circumference of the upright wall 1B of the manhole 1. The bottoms of the pre-rotation sections 3A and 3B are manhole 1 by anchor bolts 19 and nuts 19A.
Is fixed to the bottom member 1A.

As described above, the mortar or concrete 18 placed in the first space 24A and the second space 24B is used.
After curing and curing, the pumps P1 and P2 are lowered along the guide wires 20 and 20 from the upper end opening of the manhole 1 and the discharge port of the pump P1 is connected to one end of the discharge curved pipe 9A, and the discharge port of the pump P2 is formed. Is connected to one end of the discharge curved pipe 9B. As a result, the suction port 13 of the pump P1 is inserted into the pre-rotation section 3A, and the suction port 13 of the pump P2 is inserted into the pre-rotation section 3A.
B is inserted. The lower end of the discharge pipe 11A is connected to the other end of the curved discharge pipe 9A, and the lower end of the discharge pipe 11B is connected to the other end of the discharge curved pipe 9B. The outlet at the upper end of the discharge pipes 11A and 11B is the header pipe 2
1 is connected to a drain pipe 22 outside the manhole 1.

As described above, in the manhole 1 in which the pre-swirling tank 2 made of fiber-reinforced plastic is installed, the sewage inflow pipe 23 is provided.
Sewage flows into the manhole 1 from the
When the water level rises to the operation start water level HWL of P1 and P2, the water level HWL is detected by water level detection means (not shown), and an operation start signal is output to the pump P1 or P2 based on the water level detection. By operating the pumps P1 or P2 alternately, the water level becomes the upper end level L of the pre-swirling tank 2.
After dropping to WL1, the sewage in the sewage storage section 7 flows into the pre-swirl section 3A or 3B through the inflow path 4 or the inflow path 5, and the rotation direction R1 of the pump impeller in the pre-swirl sections 3A and 3B. Pre-turn in the same direction R2. Therefore, the pump can be efficiently and smoothly sucked from the entire circumference of the suction port 13 of the pump. In addition, since solid matter such as sand mixed in the water can be collected directly below the suction port 13 of the pump, the solid matter such as sand set in the pre-swirl 3A or 3B can be easily discharged together with the water. Objects can be prevented from remaining and accumulating.

[0010]

However, in the conventional pre-rotation tank 2, the outer circumference of the pre-rotation tank 2 and the upright wall 1 of the manhole 1 are not provided.
The space 2 formed by the first space 24A and the second space 24B communicating with the first space 24A from the gap between the inner circumferences of the first space B and the second space 24B.
Since the mortar or concrete 18 is configured to be poured into the mortar 4 or the concrete 4, the mortar or concrete 1 is used in the flooded manhole 1 in which groundwater or the like leaks out.
8 is difficult to cast, and it takes a long time to cure after the casting. Therefore, the installation workability of the pre-rotation tank 2 is inferior. On the other hand, since it is difficult to cast mortar or concrete 18 over the entire area of the space 24 without gaps, the mortar or concrete 18 is used to mount the gantry 10A, 10A.
It is difficult to fix B without a gap, and a gap is easily generated between the gantry 10A, 10B and the mortar or concrete 18. When such a gap is generated, the fixing strength of the gantry 10A, 10B by the mortar or the concrete 18 is reduced, and large vibration is generated during the operation of the pumps P1, P2. Therefore, the present invention can easily install a pre-swirling tank without being affected by water discharge, even in a flood water manhole where a groundwater or the like oozes or a suction water tank of a pump, and can improve installation workability. In addition, the present invention provides a retrofitting pre-swirl tank that can easily and securely fix the gantry with mortar or concrete without gaps, increase the fixing strength of the gantry with mortar or concrete, and suppress vibration during pump operation. It is intended to be.

[0011]

In order to achieve the above object, a retrofit type pre-swirl tank according to the present invention is characterized in that a plurality of pre-swirl portions into which suction ports of a plurality of pumps are individually inserted are arranged in a longitudinal direction. The first partition wall, which is recessed downward with an offset in the width direction on the side and extends upward in the width direction on the other side of the pre-swing portion, is provided on one side of the first partition wall. The pre-swirl section is formed in a longitudinal direction into a pre-swirl section forming area and a sewage storage section on the other side of the first partition wall. The plurality of pre-swirl sections are respectively extended perpendicularly to the first partition wall toward the pre-swirl section forming area side. A second partition wall is provided for partitioning in the width direction, and the sewage in the sewage storage section is guided to each of the plurality of pre-swirl sections in a tangential direction or a direction close thereto, and pump blades are provided in the pre-swirl section. A board with an inflow path that generates a pre-swirl flow that turns in the same direction as the car's rotation In a retrofitted pre-swirling tank installed at the bottom of a manhole or a suction water tank of a pump, discharge ports of a plurality of pumps having suction ports inserted into the pre-swirling part are connected to one end, and an inlet of a discharge pipe is provided. Is provided with a plurality of pedestals for mounting and supporting the discharge curved pipe connected to the other end, and a mounting recess of the pedestal for loading and installing these pedestals is recessed downward near the plurality of pre-rotation parts. A lower region of the pre-swirl portion forming area including a lower region of the sewage storage portion and a periphery of each of the plurality of pre-swirl portions and the plurality of mounting recesses communicating with the lower region of the sewage storage portion. And open inside the manhole or the suction water tank of the pump,
A communication path is provided for communicating a lower area of the wastewater storage section and a lower area of the pre-swirl section forming area with the pre-swirl section. ADVANTAGE OF THE INVENTION According to this invention, it can omit installation of mortar or concrete to places other than the installation recessed part of several gantry, and can install it. On the other hand, after mounting and installing the gantry in each of the installation recesses of the plurality of gantry, mortar or concrete can be poured into the installation recess of each of the gantry without gaps. On the other hand, by operating the pump, sewage existing in the lower region of the sewage storage unit and the lower region of the pre-swirling unit formation region is introduced into the pre-swirl unit from the communication passage, and the lower region of the sewage storage unit and the pre-swirl unit It is possible to prevent sewage from staying in the lower region of the formation area. Therefore, the sewage existing in the lower area of the sewage storage section and the lower area of the pre-swirl section formation area is prevented from decay, and the wall of the pre-swirl tank and the concrete manhole or the suction water tank of the pump are rotten. Corrosion can be prevented.

[0012]

An embodiment of the present invention will be described below with reference to the drawings. The features of the present invention include a structure in which installation recesses of a plurality of pedestals are recessed downward near a plurality of pre-swirl units, a plurality of pre-swirl units communicating with the lower region of a sewage storage unit, and a plurality of pre-swirl units. The lower area of the pre-swirl section forming area including the periphery of each of the mounting recesses of the gantry is opened inside the manhole or the suction water tank of the pump, and the lower area of the sewage storage section and the pre-swirl section forming area are opened. The structure is provided with a communication path for communicating the lower region with the pre-rotation portion, and the other structures and operations are the same as those of the conventional example shown in FIGS. 4 to 6. The same parts as those in the conventional example are denoted by the same reference numerals.

In FIG. 1 and FIG.
Mounting recesses 25A, 2 of the gantry between 3B and first partition 8A.
5B is recessed downward. On the other hand, the lower side 24A of the sewage storage part, the lower part of the pre-swirl section forming area including the surroundings of the pre-swirl parts 3A and 3B communicating with the lower area 24A and the installation recesses 25A and 25B of the plurality of pedestals. Area 24B
To the inside of the manhole 1 and penetrate the peripheral wall of each of the pre-swirl sections 3A and 3B to form the lower area 24A of the sewage storage section and the lower area 24B of the pre-swirl section formation area into the pre-swirl section 3A. , 3B are provided.

[0014] Four through-holes (only two through-holes are shown in the drawings) formed through the bottom of each of the mounting recesses 25A and 25B of the gantry are provided on the bottom member 1A of the manhole 1. The inserted anchor bolts 17, 17 are inserted, and the upper ends thereof are projected above the bottoms of the installation recesses 25A, 25B of the gantry. Next, the gantry 10A is inserted into the mounting recess 25A of the gantry, and the mounting recess 25B of the gantry is mounted.
The anchor bolts 17 and 4 are inserted into four through holes (only two through holes are shown in the drawing) formed through the lower member 10b.
17 is inserted above the lower member 10b so as to protrude above the lower member 10b, and a nut 17A is screwed into the lower member 10b to fix the mounting recesses 25A and 25B of the gantry to the bottom member 1A of the manhole 1. Stands 10A, 10 on 25A, 25B
B is installed. Further, the bottoms of the pre-rotation parts 3A and 3B are fixed to the bottom member 1A of the manhole 1 by the anchor bolts 19 and the nuts 19A, so that the manhole 1 is secured.
After installing the pre-swirling tank 2 at the bottom of the
Mortar or concrete 18 is poured into 5A and 25B.

That is, the installation recesses 25A of the plurality of pedestals
Since the pre-swirling tank 2 can be installed by omitting the mortar or concrete casting to a location other than 25B, the pre-swirling tank 2 is installed without being affected by the flooding even in the flooded manhole 1 in which groundwater or the like oozes. It is possible to improve the installation workability of the pre-rotation tank 2. Further, since the mortar or concrete 18 can be easily poured into the installation recesses 25A and 25B of the mount without any gap, the fixing strength of the mounts 10A and 10B by the mortar or concrete 18 is increased, and the pump P
1. Vibration during P2 operation can be effectively suppressed.
Further, by operating the pumps P1 and P2, sewage present in the lower region 24A of the sewage storage portion and the lower region 24B of the pre-swirl portion forming region is introduced into the pre-swirl portions 3A and 3B from the communication passage 26 to store the sewage. Sewage can be prevented from staying in the lower region 24A of the sewage portion and the lower region 24B of the pre-swirling portion forming area, so that the lower region 24A of the sewage storage portion and the lower region 24B of the pre-swirling portion forming region can be prevented. Of the pre-swirl tank 2 and the concrete manhole 1 can be prevented from being corroded by the spoiled sewage, and the life of the pre-swirl tank 2 and the manhole 1 can be extended.

In the above-described embodiment, the pre-swirl units 3A, 3B
The lower region 24 of the sewage reservoir penetrates through each peripheral wall.
A communication path 26 is provided to connect the A and the lower area 24B of the pre-swirl section formation area 12 to the pre-swirl sections 3A, 3B. As shown in FIG. 3, the pre-swirl sections 3A, 3B are connected to each other. The communication path 27 may be provided, and the communication path 26 may be provided to penetrate the peripheral wall of the communication path 27. In addition, although the description has been given using the single-shape pre-swirl tank 2, the present invention can also be applied to the pre-swirl tank 2 that is integrally connected so as to be able to be divided into a plurality. If the pre-swirl tank 2 is integrally connected so as to be able to be divided into a plurality of parts, the pre-swirl tank 2
Is divided into a manhole 1 through a small upper opening 1C.
The pre-swirl tank 2 can be assembled inside the manhole 1. Furthermore, although the pre-swirling tank 2 installed at the bottom of the manhole 1 has been described, the present invention can also be applied to the pre-swirling tank 2 installed at the bottom of the suction water tank of the pump.

[0017]

As described above, in the retrofit type pre-swirl tank according to the present invention, the pre-swirl tank can be installed by omitting the casting of mortar or concrete at locations other than the installation recesses of the plurality of frames. In addition, even in a flood water manhole or a flood water suction tank in which groundwater or the like oozes inside, the pre-rotation tank can be installed without being affected by the water discharge, and the installation workability of the pre-rotation tank can be improved. In addition, since mortar or concrete can be easily poured into the installation recess of the gantry without gaps, the fixing strength of the gantry with mortar or concrete can be increased, and vibration during pump operation can be effectively suppressed. . Further, by operating the pump, sewage present in the lower region of the sewage storage unit and the lower region of the pre-swirl unit formation region is introduced into the pre-swirl unit from the communication passage, and the lower region of the sewage storage unit and the pre-swirl unit As sewage can be prevented from staying in the lower area of the formation area,
Prevents decay due to sewage accumulation in the lower area of the sewage storage section and the lower area of the pre-swirling area, and corrodes pre-swirling tanks, concrete manholes, concrete suction water tanks, etc. with spoiled sewage. It is possible to extend the life of the pre-swirling tank, manhole, suction water tank, etc.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a partially enlarged plan view showing another embodiment of a communication passage.

FIG. 4 is a plan view of a conventional example.

FIG. 5 is a sectional view taken along line BB of FIG. 4;

FIG. 6 is a sectional view taken along line CC of FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Manhole 2 Retrofit pre-swirling tank 3A Pre-swirling part 3B Pre-swirling part 4 Inflow path 5 Inflow path 7 Sewage storage part 8 Partition wall part 8A First partition wall 8B Second partition wall 9A Discharge curved pipe 9B Discharge curved pipe 10A Mounting stand 10B Stand 11A Discharge pipe 11B Discharge pipe 12 Pre-swirling part forming area 13 Pump inlet 18 Mortar or concrete 24A Lower area of sewage storage part 24B Lower area of pre-swirling part forming area 25A Mounting recess of mounting base 25B Installation of mounting base Recess 26 Communication path P1 Pump P2 Pump R1 Rotation direction of pump impeller R2 Rotation direction of pre-swirling flow

Claims (1)

[Claims] 1. A plurality of pre-swirl portions into which suction ports of a plurality of pumps are separately inserted are downwardly recessed at one side in the longitudinal direction with an interval in the width direction, and are provided with other pre-swirl portions. By the first partition wall extending in the width direction on the side and protruding upward,
The pre-swirl section forming area on one side of the first partition wall and the sewage storage section on the other side of the first partition wall are partitioned in the longitudinal direction, and extend to the pre-swirl section forming area side orthogonal to the first partition wall. A second partition wall is separately provided to partition the plurality of pre-swirling units in the width direction, and the sewage in the sewage storage unit is guided to each of the plurality of pre-swirling units in a tangential direction or a direction close thereto. A board-like body provided with an inflow passage for generating a pre-swirl flow swirling in the same direction as the rotation direction of the pump impeller in the pre-swirl section, and a retrofit installed at the bottom of a manhole or a suction water tank of the pump. In the pre-swirl tank, the discharge ports of a plurality of pumps each having a suction port inserted into the pre-swirl section are connected to one end, and a plurality of discharge pipes, each having an inlet of the discharge pipe connected to the other end, are mounted and supported. The mounting recesses of the gantry for loading and installing these gantry Are recessed downward near the plurality of pre-swirling units, a lower region of the sewage storage unit, and an installation recess of the plurality of pre-swirling units and the plurality of pedestals communicating with the lower region of the sewage storage unit. The lower area of the pre-swirling section forming area including the respective surroundings is opened to the inside of the suction hole of the manhole or the pump, and the lower area of the sewage storage section and the lower area of the pre-swirling section forming area. And a communication path for communicating with the pre-swirl unit is provided.