The present invention relates to an oil tanker, that is, a dedicated oil tanker carrying only crude oil, and a dual-purpose oil tanker carrying not only crude oil but also solid cargo such as ore and coal, and in particular, to an oil tanker having a cargo oil pipe and other piping structure.
In an oil tanker, as shown in
In this type of piping, the cargo oil delivery pipe 50 laid on the upper deck has a weak point in safety in terms of marine pollution of a leak accident from a cargo oil pipe and easily corrodes when exposed to waves and sea breeze and requires a large amount of money for a maintenance and inspection work. In addition, the cargo oil delivery pipe 50 laid on the upper deck is laid near the central portion of the upper deck, so that the cargo oil delivery pipe 50 obstructs the effective use of the huge upper deck and a passage of a crew and a working car in the left and right direction on the upper deck and reduces the work efficiency of a crew.
However, it is not only the cargo oil delivery pipe that obstructs the passage on the upper deck in the conventional oil tanker. Pipes laid along the upper deck in addition to the cargo oil delivery pipe include a fuel oil loading pipe, a cargo oil stripper pipe, a fire main pipe, a tank cleaning pipe, and a conduit pipe. Further, a crude oil tanker is provided with an inert gas device for preventing an explosion accident and hence has an inert gas main pipe laid on the upper deck near to a bow, the inert gas main pipe being laid from an inert gas generating device arranged in a rear portion of the hull. This also presents the same problem.
In particular, a dual-purpose oil tanker capable of carrying ore and bulk has a hatchway provided in an upper deck and hence presents a more problem for passage on the upper deck. In addition, when ore and coal are loaded, the core and the coal drop on the pipes, which presents also problems such that the pipes need to be covered with a protection cover and that a lot of time is required to remove the dropped ore and coal piled under the protective cover after loading the ore and the coal.
In a case where a cargo oil delivery pipe is broken by an accident of a cargo oil pipe, there is a possibility that marine pollution will be caused.
The problem of the present invention is to eliminate various pipes such as a cargo oil pipe from an upper deck of an oil tanker to thereby reduce marine pollution, and use effectively an area on the upper deck, as well as facilitate a passage of a crew and a working car and workability of thereof.
A cargo oil piping structure according to the present invention includes: a cargo oil delivery pipe connecting a cargo oil pump in a pump room arranged in front of an engine room in a rear portion of a hull, to a shore connection provided nearly in a central portion on an upper deck of the hull. The cargo oil delivery pipe is extended forward from the pump room, through a plurality of cargo tanks located below the upper deck of the hull, and goes up through the upper deck so as to be connected to a cross pipe which is coupled to the shore connection.
As described above, according to the present invention, it is possible to eliminate the cargo oil delivery pipe from the upper deck of the oil tanker to thereby reduce marine pollution, and use effectively the area on the upper deck, as well as facilitate a passage of a crew.
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
First, a dedicated oil tanker carrying only crude oil will be described. As shown in
The cargo tank area 14, as shown in
According to the present invention, there is provided a cargo oil delivery pipe 50 connecting a cargo oil pump 16A in a pump room 16 arranged in front of the engine room 18 in a rear portion of the hull, to a shore connection 48 provided nearly at center of the upper deck 30 of the hull. The cargo oil delivery pipe 50 is extended forward from the pump room 16, through a cargo tank area located below the upper deck 30 of the hull and goes up through the upper deck 30 so as to be connected to a cross pipe 52, which is coupled to the shore connection 48.
Here, the number of pipes of the cargo oil delivery pipe 50 is appropriately selected.
Further, there are provided cargo oil suction pipes 57 connecting the cargo oil pump 16A to, for example, the center cargo tank 34. The number of pipes of the cargo oil suction pipe 57 is appropriately selected.
In the examples shown in
It is desirable that the cargo oil delivery pipe 50 is structured without providing a pipe tunnel 42 which is extended through the cargo tank area and without being covered with anything.
Further, it is also desirable that the cargo oil delivery pipe 50 is extended through a plurality of the cargo tanks nearly to a central portion in a horizontal direction and is turned upwardly through the upper deck and to connect to the cross pipe.
There can be employed a structure in which: the cargo tank area 14 has a plurality of cargo tanks in a front and rear direction; the plurality of cargo tanks are linearly arranged; the pipe tunnel 42 is arranged in such a way as to pass through the plurality of cargo tanks and to be in contact with a longitudinal bulkhead 32 of the plurality of cargo tanks; and an uppermost portion of the longitudinal bulkhead constructs a one-side surrounding wall of the pipe tunnel 42.
An inert gas main pipe 58 for sending an inert gas from an inert gas generating device to each cargo tank can be also laid in the pipe tunnel.
In the pipe tunnel 42 can be passed not only the cargo oil delivery pipes but also almost all kinds of pipes laid in a front and rear direction on the upper deck in a conventional ship such as an inert gas pipe, a tank cleaning pipe, a fire main pipe, a conduit pipe, a cargo oil stripper pipe, and a fuel oil loading pipe. This can solve almost all problems such as passage, cleaning, and the corrosion and deterioration of the pipes on the upper deck. In this regard, the inert gas pipe, the tank cleaning pipe, and the fire main pipe need to be laid to a position close to the bow, so it is desirable to extend the pipe tunnel in which these pipes are passed to the position close to the bow.
In this way, the cargo oil delivery pipe is laid below the upper deck, or the pipe tunnel is provided and the cargo oil delivery pipe is received in the pipe tunnel. Hence, when oil leaks from the cargo oil delivery pipe, it is possible to prevent the oil from quickly flowing out into the sea and hence to improve safety. Further, the cargo oil delivery pipe is not laid on the upper deck, which can hence facilitate the passage of a crew or a working car. Still further, the cargo oil delivery pipe passed through the pipe tunnel contributes to prevention of marine pollution and is not exposed to waves and sea breeze and is reduced in the generation of rust and hence is reduced in a maintenance cost, which is different from a case where the cargo oil delivery pipes are laid on the upper deck.
There can be employed a construction in which: a ship-side ballast tank 28 is provided; the pipe tunnel 42 is arranged in such a way as to be in contact with the ship-side ballast tank 28; and the one-side surrounding wall of the pipe tunnel 42 is formed of an inner longitudinal bulkhead of the ship-side ballast tank 28.
In another example, as shown in
As shown in
A pipe tunnel 42 of a sealing structure having a nearly rectangular section is formed in such a way as to be sandwiched between an upper portion of the center cargo tank 34 and the longitudinal bulkhead 32 extended longitudinally and the hatchway 38. A surrounding wall surrounding the pipe tunnel 42 has its upper side constructed of the upper deck 30 and has its outside constructed of the longitudinal bulkhead 32 extended longitudinally, and an inner surrounding wall is formed by the use of a hatch side girder 46 provided on a lower surface of the upper deck 30. In this way, the pipe tunnel 42 has its three faces constructed of hull structure members, specifically speaking, the longitudinal bulkheads 32 extended longitudinally, the upper deck 30 and the hatch side girder 46 which are used in combination, so that the pipe tunnel 42 can be constructed at a low cost.
In this way, the pipe tunnels 42 are formed on both sides of the ship on the back of the upper deck 30 and various pipes laid conventionally on the upper deck are laid in the pipe tunnels 42.
The number of the cargo oil delivery pipes 50 extended from the pump room 16 and toward the shore connection 48 in the central portion of the hull is three in total in the case of this ship. As shown in
In addition, the pipe tunnels 42 can receive also pipes 54 connected to the shore connections 48, for example, a fuel oil loading pipe and a cargo oil stripper pipe.
This ship is constructed in such a way as to suck an inert gas (which is acquired by processing the exhaust gas of a main boiler and hardly contains oxygen) in place of outside air into the cargo tank so as to prevent an explosion accident of the cargo tank when the cargo tank is brought into a negative pressure at the time of unloading or during voyage. A pipe for sending the inert gas (inert gas pipe 58) is a large diameter pipe having a diameter nearly equal to a diameter of the cargo oil delivery pipe 50 and the inert gas pipe 58 is laid to a portion close to the bow through the pipe tunnel 42. The inert gas pipe 58 has a branch pipe (not shown in the drawing) branched therefrom and the branch pipe is passed over the upper deck and is extended to the respective cargo tanks 34, 36.
An operation of opening or closing a valve and a maintenance and inspection work are conducted in the pipe tunnel 42, so that the pipe tunnel 42 can have a plurality of doorways provided therein so as to make it possible for a crew to come in and out of the pipe tunnel 42 from the upper deck 30 and the doorways are constructed in such a way as to be closed by a water-tight door. Further, it is also important to make the interior of the pipe tunnel 42 large enough for a crew to pass through.
In order to prevent a combustible gas from storing and causing a fire accident, it is preferable to provide the pipe tunnel 42 with a ventilation device, a gas sensor, and a fire extinguisher (for example, carbon dioxide type).
In the embodiment described above, the pipe tunnels 42 are provided in the uppermost portion of the longitudinal bulkhead 32 extended longitudinally, but the pipe tunnels 42 can be arranged at appropriate positions selected in the cross section of the hull.
On the other hand, as shown in
In this example, rigidity can be increased not only by the group of stringer members 60 but also preferably by the pipe tunnels 42. Hence, if the group of stringer members 60 are not provided on the inner surface of the cargo tank 34, or even in a case where the group of stringer members 60 are provided, if the group of stringer members 60 are reduced in number, it is possible to prevent sludge from depositing in the cargo tank 34 and hence to increase the amount of the cargo oil. This can facilitate a crude oil cleaning, a tank cleaning, and a sludge unloading and, in particular, can remarkably simplify various works before docking.