JPS5948196B2 - Tanker oil leak prevention piping - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to piping for preventing oil leakage in tankers.

Most of the crude oil consumed in Japan is transported by tankers from oil-producing countries such as Berja Bay and Indonesia. In order to maintain a predetermined level of water intake and maintain proper trim balance, seawater is loaded as ballast water into some of the cargo oil tanks onboard the ship, in addition to the separate ballast tanks.

The seawater contaminated with crude oil contained in this oil tank is replaced with clean seawater at sea before it reaches the oil-producing country.

A small amount of oil is discharged overboard during this process, but
In order to prevent the ocean from being polluted by discharged oil, the work will be carried out using equipment and procedures stipulated by the Convention to ensure that the concentration and total amount of discharged oil are below certain limits.

However, as global demand for crude oil increases and international calls for marine environmental protection become stronger, movements to control this marine pollution have been strengthened, and the current focus is on separating crude oil carrying tanks from ballast carrying tanks. Toshida, a treaty regulating the structure, equipment, and operation of tankers has been adopted and is scheduled to go into effect in 1981.Governments around the world are rushing to enact domestic legislation, and tanker owners and shipyards around the world are Effective retrofitting of existing ships and appropriate design of new ships are being actively investigated, and this invention is also in line with this.

New shipbuilding under the new treaty is expected to significantly reduce oil emissions associated with normal tanker operations, but there are still other issues such as pipeline cleaning, tank cleaning, and ballast filling of cargo oil tanks during abnormally rough weather. , there remains an opportunity for contact between the oil and the sea surface.

Now, we will explain the general cargo oil pipes, ballast pipes, etc. of conventional tankers, and explain the actual situation of oil leakage accidents.As shown in Figure 1, the cargo oil pipe line A is connected to the cargo oil tank (hereinafter referred to as (abbreviated as cargo oil tank) from pump room gate valve a1 valve b, cargo oil pump P1, discharge side valve c1 valves d, f,
It can be connected to the manifold L which leads to the onshore tank via the cargo oil pipe line A, and the cargo oil loaded in the cargo oil tank is unloaded to the onshore tank through the cargo oil pipe A. Ru.

In addition, in order to supply seawater as ballast to the cargo oil tank C, one sea chest F opened at the bottom of the ship is connected to the cargo oil pipe A through a sea chest pipe H equipped with a valve 1+ Js k. The cargo oil pump P1 is connected to the suction side of the cargo oil pump P1, and the cargo oil pump P1 is connected to the discharge side of the cargo oil pump P1.
The seawater is bypassed to the cargo oil tank side of the valve on the suction side by pipe J, and the seawater is sucked by cargo oil pump P1 through sea chest F1 valves I and Jy k, A ballast pipe for the cargo oil tank is formed to supply the cargo oil tank C through the section, and the ballast pipe for the cargo oil tank that supplies the cargo oil tank C to the cargo oil tank C is formed, and the oily water that has been washed in the cargo oil tank C and the ballast that has been filled in the dirty cargo oil tank C before cleaning are formed. After the seawater is sucked by the cargo oil pump P1, the seawater is transferred to the cargo oil pipe A.
Branch from the valve e and pass through the branch pipe to the slop tank E.
The treated seawater and the clean ballast (clean seawater ballast) filled in the washed cargo oil tank are sucked by the cargo oil pump P1, and an oily water treatment pipe is formed. , valve CI C't C"+ J t
1 and is discharged to sea chest F.

After the new treaty takes effect, after the cargo oil pump P1 is discharged, the valve C+ d*
Lrn, and is discharged overboard through the oil discharge monitoring and control device n.

In order to supply seawater ballast to the separate ballast tank D, another sea chest G opened at the bottom of the ship is connected to a dedicated ballast pump P2 through a sea chest pipe K equipped with a valve Oyp.
A ballast pipe line is formed which connects to the suction side of the ballast tank D, and communicates with the separated ballast tank D via a dedicated ballast pump P2, a valve q+r on the discharge side, and a gate valve t of the sx pump room. When discharging water, the ballast pipe B is communicated with the suction side of the pump P2 via the valve U via the pipe B, and is communicated with the sea chest pipe K via the valves q, r, and y. It is now possible to discharge from Seaches) G via valve 0.

After the new treaty takes effect, after discharging from the dedicated ballast pump P2,
The ballast is discharged overboard from the valve W via the valve q1 and the ballast discharge pipe B2.

If there is some kind of accident in the separated ballast tank D or ballast pipe B and oil gets mixed into the separated ballast,
After being discharged from the dedicated ballast pump P2, it will be able to be stored in the slop tank E via the pipe system B3 via the valve v1 and the blind plate v2.

Furthermore, if the dedicated ballast pump P2 is out of order, the ballast pipe B is connected to the cargo oil pipe A via the emergency bypass pipe M1 equipped with a check valve z1 and a blind lid z2, and the ballast is discharged from the cargo oil tank in the same manner as described above. The oil will be discharged or treated using the cargo oil pump P1.

Conventional tankers are equipped with diagonal conduits and piping for cargo oil and ballast water, which poses the risk of various accidents as described below.

That is, (1) When the oil tank contains cargo oil (hereinafter simply referred to as cargo oil), the valve aHb) kt J? Since oil pressure is applied to I, oil will leak from sea chest F if the valve is not closed sufficiently or forgotten to close, or if foreign matter such as mixed paper or rust is caught in the valve.

(11) If the piping to the separate ballast tank D passes through the oil tank, if a hole develops in the piping inside the oil tank due to corrosion or damage,
If the valves t, s, u, y, p, and o have a failure as described in (1) above, oil will leak from the sea chest G.

(iii) During the loading operation, the cargo is sent from the manifold L through the valve Valve a, l)t kt
J + 1 or Benri, g.

There are concerns similar to (1) regarding routes such as L d+ C's C'' and J y 1.

(V) At the start of cleaning work on cargo oil pipeline A Cargo oil pipe A is washed using sea chest F1 valve i.

j, to slop tank E via pump P1 and valve Ctdte, and to cargo oil tank C via pipe J1 valve a, and
It is carried out to the cargo oil tank C via the valve f* g* ht x, or to the manifold L via the valve, but the oil leakage accident is most likely to occur in the cargo oil pipe A when valve j+i is opened. This is a case where the oil remaining in each branch pipe flows back through Seaches (F).

To prevent this accident, open valve 1+J and close the cargo oil pipe A valve before starting pump P1.

Between g, f, and d, valves a+ b of pipe J and pipe M1 and pipe A
The remaining oil in the tank is carefully drained into a nearby empty oil tank, or other pumps equipped with a suction pipe are used to sufficiently remove the remaining oil.

The remaining oil inside the cargo oil pump P1 is similarly sufficiently removed.

Furthermore, after thoroughly checking the water head pressure due to stuttering in the sea chest F and the water head pressure in the cargo oil pipe line A in the adjacent cargo oil tank, ensure that seawater flows through the sea chest F and into the adjacent tank. After confirming that oil backflow does not occur at the opening of sea chest F, valves J and l are opened, and then valve k is opened and pump P1 is started at the same time.

Check for an increase in the pump discharge pressure, open valve C, and pay close attention to oil backflow due to pump dripping.

Sometimes, as a method for further safety, suction is performed using another pump equipped with a suction pipe in pipe N, the degree of vacuum is increased in sea chest pipe H, valve J+1 is opened, and seawater is inflowed from sea chest F. After confirming that the water has settled down, open valve k while continuing to allow seawater to flow into sea chest F, and pump P1.
, then open valve C, wait for pump P1 to settle, and then stop the other pumps.

In order to prevent oil leaks, several workers must work together in unison, with a high degree of skill, and in good timing, requiring extremely careful attention and advanced operating techniques. .

Despite this, there is a great risk of spilling oil overboard.

M It is necessary to take exactly the same consideration as at the beginning of the work to load dirty ballast (ballast water to be put into a cargo oil tank that has not yet been cleaned) into a cargo oil tank [V], and to prevent an overboard leakage accident from a sea chest. This is when it is most likely to occur.

■ During unloading of cargo oil Sea chest pipe H was closed during unloading of cargo oil.
Valve at b1 Freight oil pump Plx valve C2d, f, g, h,
The discharge pressure of the cargo oil pump P1, which is several times (4 to 5 times) the static pressure of the cargo oil in the cargo oil tank in case (1), is the valve C's C"yJ+ 1. (i)
The risk of oil leakage is greater than in the case of

&i) During the dirty ballast processing operation, the dirty ballast is transferred to slop tank E before being discharged overboard, and after oil-water separation, only seawater with oil content below a predetermined concentration is discharged overboard.

While there is a lot of oil in the ballast passing through cargo oil pipe system A, pump P
Although the discharge pressure applied to the discharge side of No. 1, valve C'y C'' and J t 1 is slightly lower than that of QO, there is also a risk of leakage from the sea chest F.

(/il) When starting the work of loading clean ballast into the washed cargo oil tank, before starting this work, first perform the cleaning work on the cargo oil pipe A in (V), and then pour seawater into the cargo oil tank. Since the oil supply work will be carried out, the same considerations as those given at the beginning of the work are required unless the cargo oil pipe A has been thoroughly cleaned.

■ At the start of loading clean ballast into the separated ballast tank, seawater is pumped from sea chest G through sea chest pipe K equipped with valves 0+p, dedicated ballast pump P2, and valve q*r.
, Ss t to the separate ballast tank D.

Normally, there is almost no problem, but the ballast pipe B penetrates the cargo oil tank, and it is possible that oil may be found in the pipe due to some kind of accident.

Unless it has been confirmed in advance that there is no oil in the pipe, when starting the dedicated ballast pump P2, the valves p and o should be
Care must be taken when opening.

(B) During separated ballast discharge work, separated ballast is discharged from separated ballast tank D through valve t + US-specific ballast pump P2, valve q, and then further into valve W at sea.
It is discharged overboard through the
It is discharged from sea chest G via lO.

If the separated ballast pipe B is installed through the cargo oil tank, damage to the pipe within the cargo oil tank may occur.
If there is damage and there is oil in the pipe or tank,
It will be processed in slop tank E via valve v1 and blind lid v2.

However, in this case, if the valve r+'Jto has a failure as shown in (i), oil may leak from Seaches)G.

6 (D If oil enters the separated ballast pipe or separated ballast tank A) For oily ballast, use the ballast pump P2 exclusively for the valve Tsus.
, valve qtV1, the blind plate v2 is removed, and it is accommodated in the slop tank through the pipe B3, but in the case of pump P2 failure, the ballast pipe B and the cargo oil pipe A are connected to the valve z1, the blind plate Plate z2 is removed and connected with pipe M, valve tt Zl*b, cargo oil pump P1, and valve C9.
It is stored in slop tank E via d and e.

Therefore, in case (a), there is a greater risk of oil leakage than in sea chest G, and in case (←), there is a greater risk of oil leakage than in sea chest F.

As detailed above, the general cargo oil pipes, ballast pipes, etc. of conventional tankers involve the risk of oil leaking out from the sea chest, and there is always a risk of oil leaking from the sea chest. The presence of valves must be monitored, reliable valves must be kept in good condition at all times, and when starting cargo oil pumps, dedicated ballast pumps, and when handling sea chests, great care and skill must be taken when handling the sea chest. The disadvantage was that it required technology.

Despite this, it is said that 20 percent of tanker oil spill accidents fall into one of the above categories.

An object of the present invention is to provide piping for preventing oil leakage from tankers, etc., which can eliminate the problem of sloping.

The first and second inventions will be described in detail based on the embodiment shown in FIG. The check valve 3 and valves 4 and 5 on the discharge side of the pump P2 are connected to the suction side, and there is a horizontal T-shaped pipe (■) at the top, and the three ends of the T-shaped pipe H-1 , ■2. II3 riser pipe■1゜■2. ■3 are connected to each other and 2 at the top
The shape is a combination of two inverted U-shaped pipes ■ and ■, and the top is connected to the storage maximum oil level of cargo oil tank C (determined by considering the ship's trim and fluctuation of the oil level) ■ and separated ballast tank B. The above-mentioned inverted U is located above the highest storage oil level.
Connect one inverted U-shaped pipe ■ of pipes IV and V to check valve 6.
The cargo oil pipe (hereinafter referred to as cargo oil pipe) A is connected to the cargo oil pipe (hereinafter referred to as the cargo oil pipe), and another inverted U-shaped pipe V is connected to the ballast pipe B, and the cargo oil pipe A is connected to the cargo oil tank. It is used when unloading cargo oil from C to a tank on land (not shown), or when transferring tertiary ballast filled in cargo oil tank C or seawater that has been washed from cargo oil tank C to slop tank E. The pipe is connected to the manifold L connected to the land tank through the pump room's gate valve 7, valve 8, cargo oil pump PL, discharge side reverse valve 9, and valves 10, 11, and 12, and
It is branched upstream of the valve 11 and communicates with the slop tank E through the valve 13, and the ballast pipe B is connected to the pump room's gate valve 14, valve 15.1'6, oil concentration meter (2), and valve 1T, separation ballast pump P2, and discharge side check valve 3 are provided with a valve 26 downstream of the valve 26, and the top is also above the storage maximum oil level ■ of the cargo oil tank C via an inverted U-shaped pipe ■. , and communicated with the slop tank E through another inverted U-shaped conduit X branched from the top of the ship, and an automatic air suction valve x1 is provided at each of the tops.

In addition, XIII in Figure 2 is a pipe used when loading cargo oil from a tank onshore to cargo oil tank C on a ship. X■ is supplied to the cargo oil tank C, and X is a pipe with valve 21 and oil discharge monitoring and control device X■, X■ is a horizontal pipe when the oil concentration meter is not used, 22 is the valve at the top of the inverted U-shaped conduit ■; 23 is the valve at the top of the inverted U-shaped conduit ■; 2-4. is the valve at the top of the inverted U-shaped conduit■,
25 indicates the valves at the top of the inverted U-shaped conduit X, respectively.

This embodiment has an inclined configuration, and the first invention is a cargo oil pipe line A that allows cargo oil to be sent to a manifold L leading to a tank on land by a cargo oil pump P1 of a cargo oil tank C, and a ship bottom. In a tanker equipped with a ballast pipe B that allows seawater to be sent from a sea chest I to a separate ballast tank D inside the ship, which is fed to a ballast pump P2,
In the middle of the ballast pipe B, the top is connected to the ballast tank B.
An inverted U-shaped conduit ■ is provided above the highest storage oil level ■' of cargo oil tank C and the highest storage oil level ■ of cargo oil tank C, and the inverted U-shaped conduit ■
One riser pipe (1) is connected to the discharge side of the ballast pump P2, and the other riser pipe (2) is connected to the separate ballast tank D.
The above-mentioned one riser pipe (1) is connected to another riser pipe (13) whose top part is a T-shaped pipe (2) and branched from the top part, and another inverted U-shaped pipe (1) is formed. Pipe line ■U is formed, and the lower end of the riser pipe ■3 is the cargo oil tank C.
The T-shaped pipe (■) at the top of the tank is connected to the cargo oil pipe A (close to the cargo oil pipe A), and the T-shaped pipe (■) at the top is connected to the riser pipe (■1).
In addition, valve 2 is connected to each party's upstream pipe L-llll3.
2. Piping for preventing oil leakage from a tanker, characterized in that 2.23 are provided respectively.

The main points are as follows.

Since the embodiment of the first invention has an inclined configuration, when cleaning the cargo oil pipe A, the valves 24, 25, and 26 of the inverted U-shaped pipe for overboard disposal must be closed. In addition, the inverted U-shaped pipe ■ that communicates with the separated ballast tank D is put in an inoperative state by closing the valve 22 at the top, and the gate valve 7 in the pump room of the cargo oil pipe A is closed. , inverted U
Valve 23 at the top of the conduit ■, check valve 6, valve 8 of the cargo oil conduit A
1, 0.11, 12, and 18 respectively and operate the dedicated ballast pump P2, seawater is sucked from the sea chest 1 and the cargo oil pipe A is washed.

Also, when you want to fill the cargo oil tank C with water, close the valve 8 and open the pump room partition; valve 7 to separate the ballast pump P.
2, seawater is sucked from Geechs H and supplied to the cargo oil tank C. When you want to supply water to the separate ballast tank D, close the valve 23 at the top of the inverted U-shaped pipe ■, U
Open the valves 22 and 14 at the top of the pipe line ■ to turn off the pump P2.
When operated, seawater is sucked from the sea chest ■ and supplied to the separate ballast tank D.

In this case, the automatic air suction valves X at the tops of the inverted U-shaped pipes IV and V remain closed while the discharge pressure of the separation ballast pump P2 is applied to the pipes, and the tops act as siphons. When P2 is stopped and there is no discharge pressure in the pipe, it automatically opens and sucks in outside air, so the action of the siphon is broken, and since the top is above the highest storage oil level in cargo oil tank C, cargo oil tank C1 There is no possibility that the oil or oily seawater in the cargo oil pipe line A or the separated ballast tank D1 ballast from the line B will flow back over the inverted U-shaped pipes ■ and ■ to the sea chest is equipped with check valve 1, so if it can properly perform the function of check valve 10, it is Sea Chest I.)
I will not be ejected overboard.

The first invention is a dedicated ballast pump P2 which has a structure and function similar to an upward slope, and which sucks seawater from a sea chest I;
That is, the connection between the seawater pump and the cargo oil pipe A through which cargo oil drawn from the cargo oil tank C passes, that is, the oil pipe, is connected to the suction side of the cargo oil pump P1 via an inverted U-shaped pipe. Since the oil pipes are located at It is possible to wash the oil pipes with seawater and fill the oil tank with seawater without having to do so, and there is also an effect that there is no need to construct a sea chest directly connected to the oil pump.

In addition, even with conventional methods, the troublesome procedures of carefully removing oil from the oil pipe system and preventing backflow to the sea chest can be completely eliminated.

The second invention consists of a cargo oil pipe A that allows cargo oil from a cargo oil tank C to be sent to a manifold L leading to a tank on land by a cargo oil pump P1, and a sea chest located at the bottom of the ship.
A tanker is equipped with a ballast pipe B that allows seawater to be sent to a separate ballast tank D inside the ship through a ballast pump P2, and a tanker is equipped with a ballast pipe B in the middle of the ballast pipe B, where the top reaches the maximum storage capacity of the ballast tank B. An inverted U-shaped pipe V is provided above the oil level ■' and the storage maximum oil level ■ of the cargo oil tank C, and one riser pipe (■) of the inverted U-shaped pipe V is connected to the discharge side of the ballast pump P2. In addition, the other riser pipe (2) is connected to the ballast pipe line B which communicates with the separated ballast tank D, and furthermore, the top part of the riser pipe (2) is made into a T-shaped pipe H, and another riser pipe (2) is connected to the other riser pipe (2) which is branched from the top part. 3 and one of the riser pipes ■1
to form another inverted U-shaped pipe ■3, and the lower end of the riser pipe ■3 communicates with the cargo oil pipe A near the cargo oil tank C,
The T-shaped pipe (2) at the top has an automatic air suction valve (X) connected to the riser pipe (1), and each room has an upper pipe (In2). Valves 22 and 23 are provided respectively on the side communicating with I3, and the cargo oil pipe A is provided with a pipe that does not pass through the cargo oil pump P1 but communicates with the manifold L or slop tank E via valve 8'. The pipe connected to the manifold L is valve 1.
8. The ballast pump P2 is connected to the cargo oil tank C via the cargo oil pipe The end of another inverted U-shaped pipe
The gist is a piping for preventing oil leakage in tankers, which is characterized by having an automatic air suction valve installed on the top of the piping.

Since the second embodiment has a diagonal configuration, in addition to the effect of the first invention, the separated ballast pipe B may be provided with, for example, a pipe passing through a cargo oil tank. If the pipe in the cargo oil tank is damaged or contaminated with oil, open the pump room gate valve 1415.27.26 of ballast pipe B.
, open valve 25 of inverted U-shaped pipe X, and open valve 24 of inverted U-shaped pipe ■
If the separation ballast pump P2 is closed and the separation ballast pump P2 is operated, all the oily seawater in the ballast pipe B can be stored in the slop tank E. Since the valve in the pipe I' of the sea chest I is a check valve 1, the sea chest I There will be no discharge overboard through the

In addition, when it is clear that there is no oil pollution due to seawater in the separated ballast tank D, close the valve 25 of the inverted U-shaped pipe X, open the valve 24 of the inverted U-shaped pipe
If you operate the oil concentration meter ■, all of the oil can be discharged overboard.If you are concerned about oil spillage, close the horizontal pipe X■ and use the oil concentration meter ■ pipe by opening valve 16.17. This allows for reliable monitoring of oil discharge overboard.

Normally, it is discharged through an oil concentration meter, and when an abnormality occurs, it can be switched to pipe X■ and stored in a slop tank.

In addition, in the case of a breakdown of the dedicated ballast pump, the cargo oil can be discharged overboard by opening the pump room gate valve 7 and valve 8.9.10.21 of the cargo oil pipe A and operating the cargo oil pump P1. Route A has no connection with Sea Chest ■ at all times, so there is no oil leakage from Sea Chest I during unloading.

In addition, if the cleaning water from the cargo oil tank C1 cargo oil pipe A contains more oil than the specified amount, all of it will be stored in the slop tank by closing valves 11 and 21 and opening valve 13 to operate the cargo oil pump. However, if the oil pollution is below the specified level, the valve 21 can be opened to discharge the oil overboard.At this time, if the oil discharge monitoring and control device X■ is operated, the discharge of oil overboard can be strictly controlled.

Therefore, according to the present invention, if a reliable valve is used across the valve in line I' of sea chest I, there is no need to make undue effort to keep the other valves in constant condition, and the operation can be made easier. Even if the valve technology is not very proficient, or even if operated by a limited number of people, it has a particularly remarkable effect of preventing oily seawater from being discharged overboard, especially from Seaches L. be.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of a general cargo oil pipe and ballast pipe of a conventional tanker, and Fig. 2 shows a pipe for preventing oil leakage of a tanker etc. according to the present invention, where 1 is a valve, ■ is a sea chest, ■ Male sea chest pipe, ■, ■ are inverted U-shaped pipes, ■ is the highest storage oil level, L is the manifold, IX, X are inverted U-shaped pipes, XI, Xll are automatic air suction valves, ■ is horizontal conduit,
A is cargo oil pipe, B is ballast pipe, C is cargo oil tank, D is separated ballast tank, Pl is cargo oil pump, P2
indicates a dedicated ballast pump, and E indicates a slop tank.

Claims (1)

[Scope of Claims] 1. A cargo oil pipe A that allows cargo oil in a cargo oil tank C to be sent to a manifold L leading to a tank on land by a cargo oil pump P1, and seawater from a sea chest I on the bottom of the ship to be sent to a ballast pump P2. In a tanker equipped with a ballast pipe line B that can be sent to a separate ballast tank D inside the ship, there is a section in the middle of the ballast pipe B where the top reaches the highest storage oil level of the ballast tank B and the cargo oil tank C. An inverted U-shaped pipe (■) located above the highest storage oil level (■) is provided, one riser pipe (■1) of the inverted U-shaped pipe V is connected to the discharge side of the ballast pump P2, and the other riser pipe (■2) is connected to the discharge side of the ballast pump P2. are connected to the ballast pipes B communicating with the separated ballast tank D, and further,
The top part is a T-shaped pipe H, and another riser pipe ■3 branched from the top part and the one riser pipe ■1 form another inverted U.
The lower end of the riser pipe ■3 is connected to the cargo oil pipe A near the cargo oil tank C, and the T-shaped pipe at the top is connected to the riser pipe ■. The automatic air intake valve X is connected to each room's upward pipe. ■Valve 22 is connected to 3.
, 23, respectively, for preventing oil leakage from a tank. 2 Cargo oil pipe A that allows cargo oil in cargo oil tank C to be sent to manifold L leading to the tank on land by cargo oil pump P, and seawater from sea chest ■ on the bottom of the ship to separated ballast tank inside the ship by ballast pump P2. In a tanker equipped with a ballast pipe B that can be sent to D, the top of the ballast pipe B is located at the highest storage oil level ■' of the ballast tank B and the highest storage oil level ■' of the cargo oil tank C. An inverted U-shaped pipe (■) located higher up is provided, one riser (2) of the inverted U-shaped pipe (V) is connected to the discharge side of the ballast pump P, and the other riser (2) is connected to the separation ballast tank D. Another riser pipe ■3 whose top part is made into a T-shaped pipe H and branched from the top part is connected to the ballast pipe B which communicates with the other riser pipe U
The lower end of the riser pipe ■3 is connected to the cargo oil pipe A near the cargo oil tank C, and the T-shaped pipe ■ at the top is connected to the riser pipe ■1. is equipped with an automatic air intake valve ■Valve 2 is connected to 3.
2.23 are provided respectively, and the cargo oil pipe A does not pass through the cargo oil pump P1, but is provided with a through pipe that communicates with the manifold L or the slop tank E through the valve 8', and communicates with the manifold L. The intermediate pipe communicates with cargo oil tank C via valve 18 and cargo oil pipe Turn the pipe ■ toward the top 24
The end of another inverted U-shaped tube Piping for preventing oil leakage from tankers, characterized by being equipped with an air intake valve.