JP2003341787A - Tank lorry - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To quickly discharge a loaded liquid on a tank lorry which is highly viscous and often dangerous, and further reduce a quantity of the residual liquid. <P>SOLUTION: The internal bottom face of a tank filled with the liquid is formed to be downwardly inclined from both longitudinal ends of the tank toward the center and from both widthwise ends of the tank toward the center. A partition having a swell backward is provided toward the longitudinal front, and a partition having a swell frontward is provided toward the rear in the tank. These partitions form three tank chambers including the front, the center and the rear. A bottom valve is provided at the lowest position on the bottom of each tank chamber, while the bottom valve of each tank chamber is made to communicate and couple with an exhausting main pipe toward the center of the bottom of the tank. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tank truck for filling a tank with liquid, which is a dangerous substance, and for transporting the liquid.

[0002]

2. Description of the Related Art A conventional tank truck of this type, like a general tank truck, has a linear tubular body inside which is filled with and loaded with liquid, which is a dangerous substance, so that the inside of the tank is divided by a partition plate. It is divided into a tank room,
Further, a bottom valve is provided on the bottom surface of each tank chamber for unloading the liquid in each tank chamber, and this is connected to a discharge pipe provided at the bottom of the tank.

The tank is slightly lower in the traveling direction,
That is, the entire tank is attached slightly downwards,
Therefore, the discharge pipe is also arranged in the front-down direction along the bottom of the tank, whereby the liquid in each tank chamber is once sent to the front of the tank through the discharge pipe, and from this front position, the rear part of the tank truck or the left and right side surfaces of the lorry. The liquid is sent to the outside and the liquid is taken out from that position.

As described above, since it is necessary to collect the liquid in the plurality of tank chambers once at the front position and send the liquid to the rear or left and right sides from the front position, the total extension length of the discharge pipe is very long. It was Then, in the tank of such a tank truck, that is, in each tank chamber, various liquids including various oils are filled and loaded and transported, but when the viscosity of the filled liquid becomes high, each tank chamber or A large amount of residual liquid is generated in the long discharge pipe.
Therefore, it has been conventionally considered that it is difficult to fill and carry a high-viscosity liquid with a tank truck at the temperature as it is. Even with a low-viscosity liquid, if the total extension length of the discharge pipe is long as in the past, residual liquid will be generated in the tank chamber or the discharge pipe, and it will be considerable for completely discharging the residual liquid. It took time.

[0005]

Therefore, with respect to high-viscosity liquids, it is also possible to lower the viscosity by raising the liquid temperature, thereby suppressing the generation of residual liquid during unloading as much as possible, and enabling loading and transportation by tank trucks. It was done. However, if such a system is adopted and the temperature of the high-viscosity liquid is raised to a high temperature for transportation, many of them will be deteriorated or deteriorated first, and ancillary equipment for maintaining the high temperature of the tank truck and the discharge pipe. In addition, it also requires high temperature resistant equipment for loading on tank trucks and unloading side.
It was very expensive.

In view of the above-mentioned circumstances, the present invention is intended to solve the problems of the prior art, in which the inner bottom surface of the tank is directed downward from both end portions in the tank longitudinal direction and both sides in the width direction to the central portion. The liquid in each tank chamber is collected in the central part by inclining it to the central part and the liquid is discharged from the central part from the side surface and the rear part of the tank truck, so that the generation of the residual liquid during the liquid discharge is suppressed as much as possible. The main purpose is to

[0007]

The tank lorry of the invention according to claim 1 is an inner bottom surface 2 of a tank 1 for filling a liquid.
Is formed in a slanting downward shape from both end portions in the tank longitudinal direction to the central portion and from both side portions in the tank width direction to the central portion,
Inside the tank 1, a partition plate 3a having a bulge rearward is provided near the front part in the longitudinal direction, and a partition plate 3b having a bulge frontward is provided near the rear part, and these partition plates 3a, 3b are used for the front part and the central part. , Rear three tank chambers 4a, 4b, 4c
And the bottom valves 6a, 6b, 6c are provided at the lowest position of the bottoms of the tank chambers 4a, 4b, 4c, and the bottom valves 6a, 6b, 6c of the tank chambers 4a, 4b, 4c are Is connected to the main discharge pipe 7 extending in the longitudinal direction of the tank.

With the above structure, in the front tank chamber 4a,
The bottom valve 6a may be installed at the lowest position in the tank chamber in the vicinity of the bottom of the tank chamber inclined rearward and the connection of the lower part of the partition plate 3a curved rearward. Therefore, the front tank chamber 4
In the case of "a", no gap occurs at a position lower than the bottom valve 6a. As a result, in the front tank chamber 4a, the residual liquid becomes very small when the cargo liquid is discharged. Similarly, the rear tank chamber 4c becomes small. In the central tank chamber 4b, the bottom valve 6b naturally exists at the lowermost part in the center of the tank, and therefore the residual liquid becomes small when the cargo liquid is discharged. Further, since the pipe length is reduced, the amount of residual liquid inside the pipe is reduced accordingly.

The tank truck of the invention according to claim 2 is
The tank lorry according to claim 1, wherein the bottom valve at the bottom of each tank chamber is opened and closed by operating the handle shaft provided at the top of the tank to rotate the operation shaft 23 extending through the tank and extending upward. There is. With the above configuration, the bottom valve located at the bottom of the tank and at the center thereof can be opened and closed by operating the handle from the top of the tank. At this time,
Since the front partition plate 3a has a bulge on the rear side, the bottom valve 6a for the front tank chamber 4a located near the front of the partition plate 3a.
There is no inconvenience in space with respect to the operation shaft 23. The rear partition plate 3c and the operation shaft 23 of the bottom valve 6c also do not cause any inconvenience.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below based on its embodiments. 1 is a longitudinal sectional view of a tank truck according to the present invention, FIG. 2 is a bottom view of the tank truck shown in FIG. 1, FIG. 3A is a plan view showing the tank of the tank truck, and FIG. It is a side view. Tank 1
Has a double structure of an inner tank 1a and an outer tank 1b as shown in FIGS. 1 and 2, and the inner and outer tanks 1a, 1
Both b are formed in a flat cylindrical shape as shown in FIG. As shown in FIGS. 1 and 2, the tank 1 is attached to a chassis 24B of a traveling vehicle 24A.

As shown in FIG. 1, the inner bottom surface 2 of the tank 1 extends from both ends in the longitudinal direction of the tank to the central portion, and as shown in FIG.
As shown in (B), it is formed in a downward slope from both sides in the tank width direction to the central part, and the intersection of both central parts is the lowest. Further, the inside of the tank 1 is divided into three tank chambers 4a, 4b, 4c by two partition plates 3a, 3b provided in the longitudinal direction. Further, a bottom valve 6b with an emergency shutoff valve 5b is provided at the lowest position of the bottom surface 2 of the central tank chamber 4b (the intersection of the above-mentioned central portions), and swells even in the tank chambers 4a and 4c before and after the emergency shutoff valve 5b. Since the partition plates 3a and 3b are provided with anti-bulging sides, the bottom valves 6a and 6c with the emergency shutoff valves 5a and 5c are provided at the lowest positions of the bottom surface of the tank chamber. In addition, in the upper part of the tank 1, each tank chamber 4a, 4
Liquid filling ports 8a, 8b, 8c for filling the liquid in b, 4c
Is provided.

As shown in FIGS. 1 and 2, the emergency shutoff valves 5a, 5b and 5c-equipped bottom valves 6a, 6b and 6c are discharge valves extending in the tank longitudinal direction at the bottom central portion of the tank 1. The main pipes 7 are connected to each other. A discharge pipe 9 extending to one side surface portion of the tank truck orthogonal to the main pipe 7 is connected to the central portion of the discharge main pipe 7 in the longitudinal direction, and an opening / closing valve 10 is provided on the discharge end side of the discharge pipe 9. There is.
From this side discharge pipe 9, a discharge pipe 11 which extends in a relatively short direction to the rear side of the tank 1 in parallel with the main discharge pipe 7 is branched, and the branch discharge pipe 11 has the opening / closing valve 1 on the branch end side thereof.
2 is provided, and on the lower side (rear side) of the opening / closing valve 12, a solution sending pump 14 with a solution sending direction switching valve 13 is provided. As can be seen from FIG. 1, the main discharge pipe 7 is formed in a downwardly inclined shape from both ends to the central part, and is at the lowest position almost at the central part, and the discharge pipe 9 is horizontally piped at this lowest position. There is.

The liquid feed pump 1 is attached to the discharge pipe 11 branched from the side discharge pipe 9 extending to one side surface of the tank truck.
A pair of side discharge pipes 15 and 16 branching from the lower side of the tank 3 and extending to both side surfaces of the tank truck are connected to each other, and the opening / closing valves 17 and 1 are provided on the discharge end sides of the side discharge pipes 15 and 16, respectively.
8 is provided, and a rear discharge pipe 19 extending toward the rear of the tank truck is branched from one side discharge pipe 15 of the both side discharge pipes 15 and 16. The rear discharge pipe 19 is branched to the rear discharge pipe 19. On-off valves 20 and 21 are provided on the end side and the discharge end side, respectively.

As shown in FIG. 1, each of the bottom valves 6a, 6b and 6c is provided with a well-known operation shaft 23 with a handle 22 which penetrates the tank 1 in the vertical direction, and the operation shaft 23 is provided from the top of the tank 1. By rotating the handle 22 forward and backward by the handle 22, the bottom valves 6a, 6
b and 6c can be opened and closed. Since the front and rear bottom valves 6a, 6c are located in the opposite direction to the bulging partition plates 3a, 3b adjacent to each other, the operation shafts 23 and the partition plates 3a, 3b of these bottom valves are located. The bulge does not cause any inconvenience in space. Further, the bottom valves 6a, 6b, 6c are provided with emergency shutoff valves 5a, 5b, 5c, which are well known and will not be described.

Liquid feed pump 1 with the liquid feed direction switching valve 13
4, the openings 25a and 25b communicating with the discharge pipe 11 are provided on both side surfaces, and the discharge port 14a of the liquid feed pump 14 is provided on the lower surface thereof, as shown in FIGS.
And openings 25c, 2 communicating with the suction port 14b, respectively.
A valve body 26 having a substantially U-shaped vertical cross section is rotatably disposed in a casing 25 provided with 5d, and the intake port 14b is provided on the valve body 26 with the left and right discharge pipes 11 and 11 or the discharge port 14a.
Is formed with a flow passage 26a selectively communicating therewith, and an operating rod 27 is integrally connected to the valve body 26.
Reference numeral 28 is a pressure adjusting valve for allowing the high pressure liquid on the discharge port 14a side to escape to the suction port 14b side.

In the liquid discharging operation of the tank truck having the above-described structure, the opening / closing valve 12 on the upper side of the liquid feed pump 14 in the discharge pipe 11 is closed and any of the tank chambers 4a, 4b, 4c is closed. Bottom valve 6a,
By opening 6b, 6c and opening / closing valve 10 on the discharge end side of side discharge pipe 9 connected to main discharge pipe 7, liquid in any of tank chambers 4a, 4b, 4c is discharged. It can be naturally discharged from the main pipe for use 7 to one side of the tank truck through the side discharge pipe 9. Further, the discharge amount can be adjusted by opening / closing the opening / closing valve 10.

When the liquid delivery pump 14 is forcibly discharged, the opening / closing valve 10 of the side discharge pipe 9 is closed, and the opening / closing valve 12 of the discharge pipe 11 branched from the side discharge pipe 9 is opened. When the switching valve 13 is operated in the normal liquid feeding direction in which the liquid is fed from the upper side to the lower side of the discharge pipe 11, the liquid feed pump 14 is operated, and the liquid in the tank chambers 4a, 4b, 4c is discharged. The branch discharge pipe 1 from the main pipe 7 through the side discharge pipe 9
It will flow to the 1 side. Therefore, when discharging from one side discharge pipe 15 of the side discharge pipes 15 and 16 connected to the discharge pipe 11, to the other side discharge pipe 1
By closing the open / close valve 18 on the 6 side, closing the open / close valve 20 on the upper side of the rear discharge pipe 19 respectively, and opening the open / close valve 17 on the side discharge pipe 15 on one side, either of the tank chambers is opened. The liquids 4a, 4b and 4c are discharged into the main pipe 7 for discharge.
The liquid can be forcibly discharged to one side of the tank truck via the liquid delivery pump 14 of the discharge pipe 11 and the one side discharge pipe 15 described above. The other side discharge pipe 16
When the tank truck is forcibly discharged to the other side, the on-off valve 17 on the one side discharge pipe 15 side is closed and the on-off valve 18 on the other side discharge pipe 16 is opened.

When the liquid delivery pump 14 is used to forcibly discharge from the rear discharge pipe 19 to the rear side of the tank truck, the opening / closing valves 17 and 18 of the both side discharge pipes 15 and 16 are closed, and the rear discharge pipe 19 is improved. On-off valve 2 on the side
0 to open the open / close valve 2 on the discharge end side of the rear discharge pipe 19
1 to open either tank chamber 4a, 4
The liquids b and 4c can be forcibly discharged to the rear side of the tank truck through the rear discharge pipe 19. Further, when the residual liquid in the main discharge pipe 7 and the side discharge pipe 9 is forcibly discharged by the liquid feed pump 14, the liquid feed pump 14
The liquid feeding direction may be switched by the switching valve 13 in the opposite direction.

The liquid in the tank chambers 4a, 4b, 4c is
When the liquid is discharged to the side of the tank truck through the side discharge pipes 15 or 16 or to the rear side of the tank truck through the rear discharge pipe 19, the liquid is not sent by the above-described forced discharge by the liquid sending pump 14. Liquid pump 1
It is also possible to stop 4 and let it discharge naturally.

As described above, the tank chambers 4a, 4b,
4c of liquid from the main discharge pipe 7 to the side discharge pipes 9, 15,
Although it is possible to naturally or forcibly discharge to the side and the rear of the tank truck through 16 and the rear discharge pipe 19, the inner bottom surface 2 of the tank 1 extends from both ends in the tank longitudinal direction to the center and both sides in the tank width direction. From the center to the central part, it is formed in a downward slope and 3
Bottom valves 6a, 6b, 6c are provided at the lowest position of each of the four tank chambers 4a, 4b, 4c, and these bottom valves 6a, 6b, 6c are connected to the main pipe 7 for discharge. Therefore, when all the liquid in the tank 1 is discharged,
The liquid in each of the tank chambers 4a, 4b, 4c can be completely dropped into the main drain pipe 7, so that even if the liquid has a relatively high viscosity, residual liquid may be generated in each of the tank chambers 4a, 4b, 4c. Absent.

After emptying the inside of the tank 1 as described above,
When cleaning the drainage pipe portion below the tank 1, the bottom valves 6a, 6b, 6c of the tank chambers 4a, 4b, 4c are closed and provided in the discharge pipes 9, 11, 15, 16, 19. This pressurizing steam is opened by opening the on-off valves 10, 12, 17, 18, 20, 21 and pressurizing, for example, steam from the discharge end of the side discharge pipe 9 connected to the discharge main pipe 7. Is introduced into the main discharge pipe 7 and the discharge pipe 11 from the side discharge pipe 9, and the steam introduced into the discharge pipe 11 passes through the side discharge pipes 15 and 16 and further to the rear discharge pipe 1.
It is discharged through the discharge end of each discharge pipe 15, 16, 19 through 9 and thereby the inside of these pipes can be thoroughly cleaned. The supply point of the steam may be any discharge end of the discharge pipes 9, 15, 16, and 19. Further, instead of steam, water may be supplied under pressure. When washing with water, the liquid feed pump 14 may be operated.

Further, in this tank truck, as described above, the inner bottom surface 2 of the tank 1 is formed so as to be inclined downward from both end portions in the tank longitudinal direction to the central portion and from both side portions in the tank width direction to the central portion. At the lowest position of each tank chamber 4a, 4b, 4c, bottom valves 6a, 6b,
6c is provided, and these bottom valves 6a, 6b, 6c are connected in communication with the main discharge pipe 7, and the main discharge pipe 7 is connected to a side discharge pipe 9 extending to one side of the tank truck. To the discharge pipe 11 branched from the discharge pipe 9, a pair of side discharge pipes 15 and 16 extending from the lower side of the liquid feed pump 14 to both side surfaces of the tank truck are connected.
Since the rear discharge pipes 19 extending from the one side discharge pipes 15 and 16 to the rear of the tank truck are branched, the discharge pipes can be concentrated in the central portion of the bottom of the tank 1 and the total discharge pipes can be concentrated. The extension length can be shortened as much as possible,
As a result, the residual liquid inside the discharge pipe can be suppressed as much as possible, and the residual liquid can be easily discharged.

In the illustrated embodiment described above, adapted to the structure of the tank, as shown in FIGS. 1 and 2,
A pair of side discharge pipes 15 extending from the lower side of the liquid feed pump 14 to both side surfaces of the tank truck are connected to a discharge pipe 11 that is branched from a side discharge pipe 9 that is connected to the discharge main pipe 7 and extends to one side surface of the tank truck. , 16 is connected and a rear discharge pipe 19 extending from one of the both side discharge pipes 15 and 16 to the rear of the tank truck is branched, and the pipe adapted to the tank of the present invention is It is not limited to the configuration.

That is, a discharge pipe (corresponding to the discharge pipe 11 in FIG. 2) extending from the side discharge pipe 9 connected to the main discharge pipe 7 and extending to one side surface of the tank truck to the rear part of the tank truck.
And a liquid feed pump 14 is provided in the branch discharge pipe, and an opening / closing valve (FIG. 2) is provided on the branch end side of the branch discharge pipe.
(Corresponding to the on-off valve 12) and an on-off valve (corresponding to the on-off valve 21 in FIG. 2) on the discharge end side. In this case, the piping is extremely simple, and the total extension length of the discharge pipe can be minimized, but the liquid is discharged at two places, one at the side of the tank truck and one at the rear. It can be performed.

Further, a side discharge pipe 11 branched from a side discharge pipe 9 extending to one side surface of the tank truck is provided with another side discharge pipe extending from the lower side of the liquid feed pump 14 to the other side surface portion of the tank truck (FIG. 2). (Corresponding to the side discharge pipe 15) and an opening / closing valve (corresponding to the opening / closing valve 17 in FIG. 2) on the discharge end side thereof.
Is provided, a rear discharge pipe (corresponding to the rear discharge pipe 19 in FIG. 2) extending from the other side discharge pipe to the rear of the tank truck is branched, and an opening / closing valve (FIG. 2) is provided on the branch end side of the rear discharge pipe.
2) and an opening / closing valve (corresponding to the opening / closing valve 21 in FIG. 2) on the discharge end side. In this case, the piping can be simple and the total extension length of the discharge pipe can be sufficiently shortened, and the liquid can be discharged at three positions, that is, two side portions and one rear portion of the tank truck.

[0026]

According to the tank truck of the first aspect of the present invention, the inner bottom surface of the tank is formed so as to extend downward from both end portions in the tank longitudinal direction to the central portion and downward from both side portions in the tank width direction to the central portion. In the longitudinal direction, a partition plate with a bulge in the rear is provided near the front part in the longitudinal direction, and a partition plate with a bulge in the front is provided near the rear part, and these partition plates enable the three tank chambers of the front part, the central part, and the rear part to be provided. And a bottom valve is provided at the lowest position of the bottom of each tank chamber, and the bottom valve of each tank chamber is connected to the main discharge pipe extending in the tank longitudinal direction at the center of the tank bottom. , When all the liquid in the tank is drained, the liquid in each tank chamber can be completely dropped into the main pipe for draining, and therefore, even if the liquid has a relatively high viscosity, residual liquid may be generated in each tank chamber. Absent.

According to the tank lorry of the second aspect of the invention, the bottom valve of the chamber of each tank of the tank lorry of the first aspect is opened and closed by forward and reverse rotations of the tank lorry, and the operation shaft has a space with the bulge portion of the partition plate. Since it does not interfere with, it can be connected to the handle at the top of the tank without any difficulty. For this reason,
The bottom valve at the bottom of the tank chamber and in the center can be opened and closed by operating the handle.

In addition to the structure of the tank chamber, as in the embodiment, a discharge pipe extending to one side surface of the tank truck is connected to the main discharge pipe, and an opening / closing valve is provided on the discharge end side of the discharge tank. By branching the discharge pipe extending from the pipe to the rear part of the tank truck and providing a liquid sending pump on this branch discharge pipe, and providing an opening / closing valve on the branch end side and the discharge end side of this branch discharge pipe, When discharging, by closing the on-off valve on the upstream side of the liquid delivery pump in the branch discharge pipe, open any bottom valve of the tank chamber, and open the on-off valve of the side discharge pipe, The liquid in any of the tank chambers can be naturally discharged from the main discharge pipe through the side discharge pipe to one side of the tank truck without using a liquid feed pump, and the side discharge pipe can be opened and closed. Close the valve and Opening the discharge end side switching valve of the tube, it is possible to naturally discharge the liquid in the tank chamber to the rear side of the tank truck. Further, in the case of performing forced discharge by the liquid feed pump, the on-off valve of the side discharge pipe is closed, the on-off valve of the branch branched from this side discharge pipe is opened, and the liquid feed pump in this discharge pipe is opened. The liquid in the tank chamber can be forcibly discharged to the rear side of the tank truck by operating the. In particular, according to this configuration, since the drainage pipes are concentrated in the central portion of the tank bottom and the pipes are extremely simple, the total extension length of the discharge pipes can be minimized, but it is required at the minimum. The liquid can be discharged at two locations, one on the side of the tank truck and one on the rear. Therefore, the effect of the present invention is further enhanced.

Further, when cleaning the drainage pipe section below the tank, the bottom valve of each tank chamber is closed and the opening / closing valve provided in each of the discharge pipes is opened to connect to the main discharge pipe, for example. By supplying steam or the like from the discharge end of the side discharge pipe, the inside of these drainage pipes can be almost completely cleaned, and the cleaning work can be performed easily and easily.

Further, a side discharge pipe branched from a side discharge pipe connected to the main discharge pipe and extending to one side face of the tank truck, and another side discharge pipe extending from the lower side of the liquid feed pump to the other side face of the tank truck. Is provided with an opening / closing valve on the side of the discharge end, the rear discharge pipe extending from the other side discharge pipe to the rear of the tank truck is branched, and the branch end side and the discharge end side of the rear discharge pipe are connected. If an on-off valve is provided on
Since the liquid discharging work can be performed at three places, that is, two places on the side of the tank truck and one place on the rear, workability is improved.

Further, a pair of side discharge pipes extending from the lower side of the liquid feed pump to both side faces of the tank truck are connected to the discharge main pipe and branched from a side discharge pipe extending to one side surface of the tank truck. When connecting and branching the rear discharge pipe extending from one of the two side discharge pipes to the rear of the tank truck, and providing an opening / closing valve on the branch end side and the discharge end side of this rear discharge pipe, the tank truck The liquid can be discharged at four positions, three on the side and one on the rear, and the liquid can be forcibly discharged by the liquid-sending pumps at two positions on both sides of the tank truck, further improving workability. Further, in this case, the side discharge pipe connected to the main discharge pipe and extending to one side surface of the tank truck can be used as the cleaning port. With these configurations, the effect of the present invention is further enhanced.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a tank truck according to the present invention.

FIG. 2 is a bottom view of the tank truck shown in FIG.

FIG. 3A is a plan view showing a tank of a tank truck, and FIG. 3B is a cross-sectional view of the tank.

FIG. 4 is a vertical cross-sectional view of a main part of a liquid feed pump with a switching valve.

5 is a cross-sectional view taken along the line YY of FIG.

[Explanation of symbols]

1 tank 2 Inside bottom of tank 3a, 3b Partition plate 4a, 4a, 4c Tank chamber 6a, 6b, 6c Bottom valve 7 Discharge main pipe 9,15,16 Side discharge pipe 11 discharge pipe 19 Rear discharge pipe 10, 12, 17 on-off valve 18, 20, 21 open / close valve 13 Switching valve 14 Liquid feed pump 22 handle 23 Bottom valve operating shaft

Claims (2)

[Claims] 1. An inner bottom surface of a tank filled with a liquid is formed in a slanting downward shape from both end portions in the tank longitudinal direction to the central portion and from both side portions in the tank width direction to the central portion. A partition plate with a bulge on the rear side is provided on the rear side, and a partition plate with a bulge on the front side is provided on the rear side. These partition plates form three tank chambers at the front, center, and rear, and the bottom of each tank chamber. A tank truck that has a bottom valve at the lowest position and has the bottom valve of each tank chamber connected to the main discharge pipe at the center of the tank bottom. 2. The bottom valve can be opened and closed by rotating an operation shaft vertically penetrating the tank by operating a handle provided on the top of the tank. Item 1. A tank truck according to item 1.