JPH07215125A - Tank lorry - Google Patents

Abstract

PURPOSE:To surely recover the vapor, and to improve the safety by providing a vapor valve for recovering the gaseous vapor generated from the liquid in the upper part of a tank, and providing a bottom valve in the lower part of the tank, and switching the bottom valve to OPEN under the condition that the vapor valve is switched to OPEN. CONSTITUTION:A vapor valve 24 of a vapor recovering device 20 is provided in the upper part of each tank chamber 10 of a tank 7, and a bottom valve 6 is provided in the lower part of each tank chamber 10, and the bottom valve 6 can be switched to OPEN under the condition that the vapor valve 24 is switched from CLOSE to OPEN. An air pipeline 29 from an air tank 2 is divided in the downstream of a main valve 3, and one branch is connected to an air inlet/outlet S of the vapor valve 24, and the other branch is connected to an air inlet/outlet P and the other air inlet/outlet R of a pilot valve 30, and connected to an air inlet/outlet T of the bottom valve 6 through an air pipeline 31. As a result, the bottom valve 6 can not be switched to OPEN unless the vapor valve 24 is switched to OPEN.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a tank truck.
That is, the present invention relates to a tank truck that carries a volatile liquid such as gasoline, light oil, or kerosene in a tank for transportation.

[0002]

2. Description of the Related Art In a tank truck of this type, a volatile liquid is loaded on a vehicle from a storage tank or the like of a loading facility through an inlet at the top of the tank or a bottom valve at the bottom of the tank using a pump. After being loaded into the tank, loaded and transported, it is unloaded to the underground tank of the unloading facility via the bottom valve. By the way, when a volatile liquid is loaded from the storage tank of the loading facility into the vehicle-mounted tank, gaseous vapor is generated from the liquid in the vehicle-mounted tank, and it is loaded in the vehicle-mounted tank. Similarly, when a volatile liquid is unloaded into an underground tank or the like of an unloading facility, gaseous vapor is similarly generated from the liquid in the underground tank or the like. This gaseous vapor has the risk of explosion and is harmful and may cause pollution.Therefore, in this type of tank truck, a vapor recovery device for recovering gaseous vapor is attached to the top of the tank. It had been. Then, through the vapor valve of this vapor recovery device, the gaseous vapor generated in the vehicle-mounted tank at the time of loading can be recovered in the storage tank or the like of the loading facility, or
At the time of unloading, the gaseous vapor generated in the underground tank of the unloading facility was collected in the onboard tank so that it would not be released to the outside.

Now, such a bottom valve and a vapor valve are, for example, of an air opening / closing type, and FIG. 4 is an air circuit diagram of a conventional example thereof. Then, the air in the air tank 2 accumulated in the compressor 1 is diverged in the middle by opening the main valve 3.
Is supplied to the opening / closing operation part of the vapor valve 5 and the bottom valve 6 through the above, and thus, at the time of loading and unloading using the above-mentioned pump, the vapor valve 5 and the tank 7 above the tank 7
The bottom valves 6 in the lower part of the above were switched from closed to open.

[0004]

By the way, the following problems have been pointed out in such a conventional example. That is, the vapor valve 5 and the bottom valve 6 have conventionally been designed so that both can be switched to open as necessary in the air circuit shown in FIG. 4, but the vapor valve 5 does not switch to open and only the bottom valve 6 opens. There is a problem that the vapor valve 5 is closed and the loading and unloading from the open bottom valve 6 progresses with the vapor valve 5 closed, which may hinder the recovery of the gaseous vapor described above. It was. Such an accident is caused by a failure of the vapor valve 5 itself, a failure of the air pipe 4 to the vapor valve 5 at a bent portion in the middle, and an obstruction of the air flow. But
In particular, when such an accident occurs during loading from the bottom valve 6 using a pump, the tank 7 is opened via the bottom valve 6 that is open.
The pressure in the tank 7 rises due to the volatile liquid loaded therein and the gaseous vapor generated from the liquid. Then, since the vapor valve 5 remains closed, the safety valve attached to the upper part of the tank 7 is automatically switched from closed to open, and the gaseous vapor is discharged to the outside through this safety valve and the volatile liquid is discharged. Was sometimes leaked to the outside, which was a problem. As described above, in the conventional example, the recovery of the gaseous vapor may be hindered, the vapor may be discharged to the outside, or the volatile liquid may flow out to the outside, which may cause an explosion and be harmful. There was a risk of pollution.

In view of such circumstances, the present invention has been made to solve the problems of the above-mentioned conventional example, and the bottom valve can be switched to the open condition on condition that the vapor valve is switched to the open condition. Therefore, it is an object of the present invention to propose a tank truck in which gaseous vapor generated from a volatile liquid is reliably collected and is not released to the outside, and the volatile liquid does not flow out to the outside.

[0006]

The technical means of the present invention for achieving this object are as follows. That is, the tank lorry is a tank lorry that carries and transports a volatile liquid in a tank, and a vapor valve for collecting gaseous vapor generated from the liquid is attached to the upper part of the tank, and A bottom valve is attached to the lower portion of the tank, and the bottom valve can be switched from closed to open on condition that the vapor valve is switched from closed to open.

[0007]

Since the present invention comprises such means, it operates as follows. In this tank lorry, volatile liquids are loaded into the tank from the loading facility via the upper inlet, or by using a pump through the lower bottom valve, loading,
After transportation, it is unloaded to the unloading facility via the bottom valve. By the way, when loading a volatile liquid, gaseous vapor is generated in the tank, and when unloading, gaseous vapor is generated in the unloading facility. And this gaseous vapor is
Through a vapor valve provided at the upper part of the tank, the material is collected from the inside of the tank to the loading equipment and also from the inside of the unloading equipment to the tank.

In this tank lorry, the bottom valve can be switched to the open condition on condition that the vapor valve is switched to the open condition. Therefore, when loading or unloading using the pump from the opened bottom valve, the vapor valve is always opened, and the recovery of the gaseous vapor is surely performed without any trouble. In particular, when loading from the bottom valve using a pump, it is possible to reliably prevent the gaseous vapor in the tank from being discharged to the outside and the volatile liquid from flowing out to the outside via the safety valve.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on the embodiments shown in the drawings. 1, FIG. 2 and FIG. 3 show an embodiment of the present invention, and FIG. 1 (1) is its air circuit diagram, FIG.
(2) is an explanatory view of the pilot valve, FIG. 2 is a vertical sectional view of the vapor valve, and FIG. 3 is a plan view of the vapor valve. FIG. 5 is a plan view of the tank lorry, and FIG. 6 is a rear view illustrating a state in which the tank lorry is unloaded.

First, the tank truck will be described with reference to FIGS. 5 and 6. This tank lorry carries a volatile liquid 8 in a tank 7 and transports it.
A partition plate 9 extending in the width direction divides the inside into tank chambers 10 of 2 to 7 chambers (4 chambers in the illustrated example). Then, gasoline, light oil, kerosene, and other volatile liquids 8 are discharged from a storage tank (not shown) of the loading facility via, for example, an inlet 11 provided at the top of each tank chamber 10 (so-called top loading method). Alternatively, a bottom valve 6 attached to the bottom of each tank chamber 10 using a pump (so-called bottom loading method) is used to load each tank chamber 10 to the destination unloading facility,
Be transported. At the destination, for example, unloading is performed on the underground tank 12 of the unloading facility such as a gas station. In the example of FIG. 6, the bottom valve 6 of the tank chamber 10 of the tank 7 is
(See (1) of FIG. 1, FIG. 4, etc.), the piping 13 under the tank 7, the discharge port 14, the unloading hose 15, the underground piping 16 on the side of the underground tank 12, the tank room 10 and the like. The loaded volatile liquid 8 is unloaded to the underground tank 12.

The unloading hose 15 is connected and connected between the discharge port 14 on the tank truck side and the underground pipe 16 on the underground tank 12 side for unloading. Reference numeral 17 in FIG. 5 is a manhole, and this manhole 17 is a tank chamber 1
It is attached to the upper part of 0 and is used for maintenance and the like in each tank chamber 10. 18 is a safety valve, and this safety valve 1
8 is attached to the upper part of each tank chamber 10, is used for adjusting the pressure in each tank chamber 10 and is normally closed, but the pressure in the tank chamber 10 rises above a certain value. It automatically opens and closes when it falls below a certain value. Reference numeral 19 denotes a protective frame, which is provided around the tank 7 to protect the safety valve 18, the manhole 17, the vapor recovery device 20, etc., for example, when the volatile liquid 8 which is a dangerous substance is loaded. It functions to prevent scattering and spillage accidents.

Further, in this tank truck, a steam recovery device 20 is additionally provided on the tank 7, and the steam recovery device 20
Comprises the following adapter 21, pipe 22, branch pipe 23, vapor valve 24 and the like. To describe these in detail, first, the adapter 21 is provided at the rear of the tank 7 and is provided with a valve. Collection port 25 provided at the upper part of the underground tank 12
On the other hand, it is connectable via a recovery hose 26 and a recovery pipe 27. Next, the pipe 22 is arranged in the longitudinal direction on the tank 7, and the rear end thereof is connected to the adapter 21 via the intermediate pipe 28. In addition, one end of each branch pipe 23,
It is connected to the middle or front end of the pipe 22, and the other end is connected to the upper part of each tank chamber 10 of the tank 7 via a vapor valve 24.

The opening / closing method of the vapor valve 24 and the bottom valve 6 will be described below with reference to FIGS. 1, 2 and 3. As described above, the vapor valve 24 of the vapor recovery device 20 is attached to the upper portion of each tank chamber 10 of the tank 7, and the bottom valve 6 is attached to the lower portion of each tank chamber 10 of the tank 7. The bottom valve 6 can be switched from closed to open on the condition that the vapor valve 24 is switched from closed to open.

More specifically, the vapor valve 24 and the bottom valve 6 in the illustrated example are of an air opening / closing type using a common air source. First, referring to the air circuit diagram of FIG. 1 (1), the air tank 2 stores air pressure in the attached compressor 1 and is connected to one end of an air pipe 29. Alternatively, another air tank mounted on the vehicle may be used instead of the air tank 2. This air pipe 29 is connected to the main valve 3
Is branched off after passing through the vapor valve 24.
Is connected to an air inlet / outlet S of a cylinder, which will be described later, attached to, and the other end is connected to an air inlet / outlet P of a pilot valve 30 attached to the vapor valve 24.
And another air inlet / outlet R of the pilot valve 30
Is connected to an air inlet / outlet T of an opening / closing operation portion of the bottom valve 6 via an air pipe 31.

According to FIGS. 2 and 3, the vapor valve 24
The main body 32 of the vapor valve 24 is in the form of a casing having a steam flow path 33 formed therein, and the steam inlet / outlet port 34 opening at the lower end is opened at the side end. The steam inlet / outlet ports 35 are formed, and the steam inlet / outlet port 34 and the steam inlet / outlet port 35 are connected to each other via the steam flow path 33. And such a body 32
The lower end portion of the steam inlet / outlet 34 is attached and fixed to a flange portion 36 formed in the upper portion of the tank chamber 10 of the tank 7 with a bolt or the like. Further, the steam inlet / outlet 35 at the end portion on the main body 32 side is provided with the branch pipe 23 of the steam recovery device 20 described above.
It is connected to the pipe 22, the adapter 21 and the like via (see also FIG. 5).

Reference numeral 37 is a valve seat of the vapor valve 24, and the valve seat 37 is erected on the peripheral edge of the steam inlet / outlet 34 at the lower end of the main body 32 described above. A valve element 39 is arranged on the valve seat 37 via a packing 38 so as to be in pressure contact therewith, and the steam inlet / outlet port 34 can be opened / closed. A lower end portion of a rod 40 is connected and fixed onto the valve body 39 of the vapor valve 24, and the rod 40 is connected to the vapor passage 33 in the main body 32.
While being erected inside, the upper end thereof penetrates through an opening 41 formed at the center of the upper end of the main body 32 and projects into a cylinder 42 integrally erected on the upper end of the main body 32.
The upper end of the rod 40 is in sliding contact with the opening 41 of the main body 32 via an O-ring 43 so as to be movable up and down.
Reference numeral 44 denotes a spring, and the spring 44, which is a compression spring, is interposed by the rod 40 between the upper end of the main body 32 and the valve body 39, and normally urges the valve body 39 toward the lower valve seat 37. It is pressed and the steam inlet / outlet 34 is closed.

In the cylinder 42, an air hole 52 is formed vertically within the thickness of the peripheral side portion so as to communicate with the vapor flow path 33 from the vicinity of the upper portion of the inner surface, and the body 32 of the vapor valve 24 is formed at the lower end.
A cap 45 is attached to the upper end while being integrally fixed to the upper end so as to stand upright, and a space communicating with the vapor flow path 33 is formed inside. Reference numeral 46 denotes a piston, which is integrally connected and fixed to the upper end of the rod 40, and is slidably contacted to the inner surface of the cylinder 42 via an O-ring 47 so as to be movable up and down. So,
The space inside the cylinder 42 is vertically divided by the piston 46, and the space on the lower side, that is, the space formed between the lower surface of the piston 46 and the upper end of the main body 32 is an air chamber 48. The above-mentioned air inlet / outlet S formed in the lower portion of the cylinder 42 is opened in the above.

The pilot valve 30 described above is mounted on the cap 45.
The switch 49 of 0 is the vertical hole 5 provided in the cap 45.
It projects below the lower surface of the cap 45 through 0. This pilot valve 30 is normally set to be closed, and the above-mentioned air piping 29 and the air inlet / outlet port P on the main valve 3 side are provided.
Is the air pipe 31 and the air inlet / outlet R on the bottom valve 6 side,
It has been shut off (see the upper part of Fig. 1 (2)). On the other hand, when the piston 46 comes into contact with the switch 49 from below and pushes it upward, the pilot valve 30
Is switched from closed to open, and the air inlet / outlet port P is connected to the air inlet / outlet port R (see the lower part of FIG. 1 (2)).

The present invention is constructed as described above. Then it becomes as follows. In this tank truck, the volatile liquid 8 is transferred from the storage tank of the loading facility,
It is loaded into the tank chamber 10 via the inlet 11 at the top of the tank chamber 10 of the tank 7 or via the bottom valve 6 at the bottom of the tank chamber 10 using a pump. After loading and transporting, the cargo is unloaded into the underground tank 12 of the unloading facility via the bottom valve 6 (see FIGS. 5 and 6).

By the way, when the volatile liquid 8 is loaded into the tank chamber 10 of the tank 7 of the tank truck from the storage tank of the loading facility or the like, the volatile liquid 8 is stored in the tank chamber 10.
Gaseous vapor 51 is generated from the volatile liquid 8 loaded in the tank chamber 10 when unloading the volatile liquid 8 in the underground tank 12 of the unloading facility. From this, gaseous vapor 51 is generated. The gaseous vapor 51 thus generated is recovered from the inside of the tank chamber 10 to the storage tank of the loading facility via the vapor valve 24 of the vapor recovery device 20 provided in the upper portion of the tank chamber 10, Further, it is collected from the underground tank 12 or the like of the unloading facility into the tank chamber 10 (see FIGS. 5 and 6). That is,
The gaseous vapor 51 is pushed out by the volatile liquid 8 to be loaded or unloaded, and the recovery hose 26 of the vapor recovery device 20, the adapter 21, the intermediate pipe 28, the pipe 22, the branch pipe 23, the vapor valve 24, etc. Through the order or the reverse, and is recovered in a predetermined manner.

By the way, the vapor valve 24 of the vapor recovery device 20 attached to the upper part of the tank chamber 10 of the tank 7,
The bottom valve 6 attached to the lower portion of the tank chamber 10 is normally set to be closed, and can be switched from closed to open when loading from the bottom valve 6 using a pump or unloading from the bottom valve 6. . In the illustrated example, such a vapor valve 24
The bottom valve 6 is opened / closed by an air circuit using a common air source (see FIG. 1 (1)).

That is, in such loading and unloading, first, the main valve 3 is manually operated to switch from closed to open, so that the pressurized air causes the main valve 3 opened from the air tank 2 to open. Through the air pipe 29, it reaches the air inlet / outlet S of the cylinder 42 on the vapor valve 24 (see FIG. 1 (1)). And the air inlet / outlet S
Flows into the air chamber 48 in the cylinder 42 from the above, the pressure of the pressurized air causes the pressure of the air chamber 48 to rise, the air chamber 48 is expanded upward, and the piston 46 resists the urging force of the spring 44. Raise it (see Figure 2). Therefore, the valve body 39 in the main body 32 of the vapor valve 24 is also raised via the rod 40, and the lower valve seat 3
7, the vapor inlet / outlet 34 of the main body 32 of the vapor valve 24 is opened. In this way, the normally closed vapor valve 24 is switched from closed to open (see FIG. 2).

When the vapor valve 24 is switched from the closed state to the completely opened state in this way, the air pushed out by the piston 46 that has risen in the cylinder 42 is discharged to the vapor flow path 33 through the air hole 52. Further, the lifted piston 46 abuts against the switch 49 of the pilot valve 30 from the lower side and pushes it upward, so that the pilot valve 30 is switched from the normally closed state to the open state. That is, the air inlet / outlet P and the air inlet / outlet R of the pilot valve 30 which have been blocked until then are connected, and the pressurized air from the side of the air tank 2 or the main valve 3 which is opened is connected to the air pipe 29 and the pilot valve 30. Through the air inlet / outlet port P, the air inlet / outlet port R, etc. Then, since it reaches the air inlet / outlet T of the opening / closing operation portion of the bottom valve 6 via the air pipe 31, the bottom valve 6 which has been set to be normally closed is switched from closed to open (see FIG. 1 (1)). ).

As described above, in this tank truck, first, the vapor valve 24 is switched to the open condition, and then the bottom valve 6 is switched to the open condition. That is, if the vapor valve 24 does not switch from closed to open due to a failure of the vapor valve 24 itself or some other cause, the bottom valve 6 also does not switch from closed to open. Therefore, when loading and unloading using the pump from the opened bottom valve 6, the vapor valve 2 is used.
4 is also always open, and unlike the conventional example of this kind in FIG. 4 described above, loading and unloading do not proceed from the bottom valve 6 that is open with the vapor valve 5 closed, and The recovery of the gaseous vapor 51 generated from the volatile liquid 8 is surely performed without any trouble. In particular, when loading from the bottom valve 6 using a pump, it is ensured that the gaseous vapor 51 in the tank chamber 10 is released to the outside from the safety valve 18 and further the volatile liquid 8 flows out to the outside. To be prevented. That is, as in the conventional example of this kind in FIG. 4 described above, loading proceeds from the open bottom valve 6 with the vapor valve 5 closed, and the volatile liquid 8 to be loaded and the generated gaseous vapor 51. As a result, the pressure in the tank chamber 10 rises, and the safety valve 18 at the upper part of the tank chamber 10 is automatically switched from closed to open, so that gaseous vapor 51 is released from the tank chamber 10 or volatile liquid. 8 is surely prevented from flowing out.

First, in this tank truck, the air circuit of FIG. 1 (1) described above is adopted, and the vapor valve 24 is switched to the open condition.
The bottom valve 6 is switched to open, and the opening of the vapor valve 24 is mechanically confirmed using air. Therefore, these are realized more reliably and with less failure,
There is an advantage.

Secondly, in this tank lorry, the air circuit of FIG. 1 (1) is adopted in this way to confirm the opening of the vapor valve 24, but the present invention is not limited to this. Rather, it is possible, for example, to do this electrically. That is, it is also possible to electrically detect that the vapor valve 24 has been switched to open, and switch the bottom valve 6 to open based on the detection signal. Thirdly, in the air circuit of FIG. 1 (1), a manually operated auxiliary valve is provided in the air pipe 31 between the pilot valve 30 and the opening / closing operation portion of the bottom valve 6. You may do it. The sub valve is normally set to open, and when loading into the tank chamber 10 through the inlet 11 (see FIG. 5), the bottom valve 6 is closed by switching to closed. Vapor valve 24
It is also possible to open only.

Fourthly, in the example shown in FIG. 6, the gaseous vapor 51 generated in the underground tank 12 of the unloading facility at the time of unloading is collected in the tank chamber 10 of the tank truck. However, instead of this, the gaseous vapor 51 may be directly discharged from the underground tank 12 or the like to the outside. Fifthly, in this case, the vapor valve 24 is manually operated separately to be closed and the bottom valve 6 is also manually operated to be opened. It is conceivable to open both together and open the vapor valve 24 side to the atmosphere without connecting to the underground tank 12 of the unloading facility or the like to introduce atmospheric pressure into the tank chamber 10. As a result, the discharge of the volatile liquid 8 from the inside of the tank chamber 10 and the unloading of the underground tank 12 or the like via the bottom valve 6 are made smoother. In this way, the vapor valve 24 can be used not only for recovering the gaseous vapor 51 but for unloading promotion.

[0028]

As described above, the tank truck according to the present invention exhibits the following effects by making it possible to open the bottom valve on condition that the vapor valve is opened.

That is, when loading or unloading from the open bottom valve, the gaseous vapor generated from the volatile liquid is surely recovered via the open vapor valve. In particular,
When loading from the bottom valve using a pump, the safety valve prevents the gaseous vapor in the tank from being discharged to the outside, and further prevents the volatile liquid from flowing out to the outside. Therefore, the danger of explosion is avoided,
The safety is significantly improved by eliminating the risk of pollution. Thus, the effects of the present invention are remarkably great, such as the problems existing in this type of conventional example are eliminated.

[Brief description of drawings]

FIG. 1 shows an embodiment of a tank truck according to the present invention,
(1) is an air circuit diagram thereof, and (2) is an explanatory diagram of the pilot valve thereof.

FIG. 2 is a vertical cross-sectional view of the vapor valve of the same embodiment.

FIG. 3 is a plan view of the vapor valve of the same embodiment.

FIG. 4 is an air circuit diagram of a tank truck of this type of conventional example.

FIG. 5 is a plan view of a tank truck.

FIG. 6 is a rear view showing the state of unloading from the tank truck.

[Explanation of symbols]

 6 Bottom valve 7 Tank 8 Liquid 24 Vapor valve 51 Steam

Claims (1)

[Claims] 1. A tank truck for loading and transporting a volatile liquid in a tank, wherein a vapor valve for collecting gaseous vapor generated from the liquid is attached to an upper portion of the tank, and the tank is provided with the vapor valve. A bottom valve is attached to the lower part of the tank lorry, and the bottom valve can be switched from closed to open on condition that the vapor valve is switched from closed to open.