Oil tanker hull assembly and method of operation

An oil tanker ship having an oil tanker hull assembly and method of operation operable to prevent oil spillage in case of an accidental hull rupture. The oil tanker assembly includes 1) an inner main tank oil cargo assembly to receive, support, and convey a primary oil cargo; and 2) an outer hull tank oil cargo assembly adapted to receive and convey a secondary oil cargo therein and mounted about and enclosing the inner main tank oil cargo assembly. The outer hull tank oil cargo assembly is provided with a plurality of compartment bulkhead assemblies operable to divide same into a plurality of spaced adjacent compartmentalized hull tanks with each one independently operable on being ruptured to prevent oil spillage into the surrounding sea water. The compartment bulkhead assemblies are each provided with an upper top surface engineered and positioned below a sea level line when obtaining a full load of oil cargo therein. A breach of a respective compartmentalized hull tank utilizes the force of gravity and pressure of sea water through the hull tank breach or rupture to move the secondary oil cargo in the ruptured compartmentalized hull tank upwardly over the top surface into adjacent ones of the compartmentalized hull tanks to prevent oil spillage to the adjacent sea water.

PRIOR ART 
A patent search was conducted on this invention and the following United 
States patent references are noted: 
______________________________________ 
U.S. Pat. No. 
Invention Inventor 
______________________________________ 
5,086,723 
DOUBLE-HULLED VESSEL 
Goldbach et al 
CONSTRUCTION HAVING 
VERTICAL DOUBLE-WALL- 
ED LONGITUDINAL 
BULKHEAD 
5,156,109 SYSTEM TO REDUCE Mo Husain 
SPILLAGE OF OIL DUE TO 
RUPTURE OF SHIP'S TANK 
5,271,350 OIL TANKER APATUS Babette B. Newburger 
5,320,055 DOUBLE-LAYERED VESSEL Robert D. Goldbach 
WALL CONSTRUCTION 
WITH LONGITUDINALLY 
STAGGERED CELL-TO-CELL 
ACCESS OPENINGS 
THROUGH WALL LAYER- 
CONNECTING PLATES 
5,349,914 LEAKPROOF OIL Lapo et al 
SUPER-TANKER 
5,520,131 APATUS AND METHOD Robert D. Goldbach 
FOR ACCOMMODATING 
LEAKED OIL WITHIN A 
DOUBLE-HULLED TANKER 
AFTER SUFFERING 
GROUNDING DAMAGE 
5,582,124 HYBRID FRAMING SYSTEM Sikora et al 
FOR VESSELS 
______________________________________ 
Enclosed is a copy of "Mobil Oil Company" disclosure of a double hulled oil 
tanker with a safety zone 13 feet wide between the hull walls. 
As we all know, a great disaster occurs when an oil tanker has its hull 
ruptured by another vessel, iceberg, or other obstacle which ten 
contaminates the surrounding sea area with spilled oil and kills wildlife. 
An oil tanker of the prior art is provided with a main tank which is filled 
with oil which may extend considerably above a surrounding water line. 
When a prior art oil tanker is ruptured and, due to higher oil level in 
the main tank, the oil is then forced outwardly by gravity pressure of the 
oil in the main tank into the surrounding sea area. 
In our invention, we have the main tank surrounded with a hull tank which 
has a physical separation or width between the walls of 5-25 feet. 
Further, along the length of the oil tanker, these hull tanks are 
compartmentalized meaning that they have separation walls or compartment 
bulkheads therein and, therefore, they are of a limited length and size. 
Oil is conveyed within that 5-25 foot hull separation area and having a 
"hull tank oil cargo line" below the water line. 
On a rupture of an outer skin of the hull tank, the sea water will rush in 
due to the greater pressure achieved by the water line being above the 
hull tank oil cargo line. This will then move the oil, which has a less 
density than the sea water, upwardly to the top of the compartment 
bulkheads which will then equalize itself when the pressure through the 
rupture line plus the oil which is moving upwardly equalizes. This will 
eliminate or greatly minimize any oil spill that may occur as a result of 
the ruptured outer skin of the hull tank. 
The Goldbach et al U.S. Pat. No. 5,086,723 discloses a double-hulled vessel 
construction having vertical double-walled longitudinal bulkhead teaching 
steel construction with curved plate panels but is not deemed pertinent to 
our invention. 
The Goldbach U.S. Pat. No. 5,320,055 discloses a double-hulled or 
double-layered vessel constructed with vertically and longitudinally 
staggered access openings. 
The Husain patent discloses a system to reduce spillage of oil due to 
rupture of ship's tank and operates on pressure differential but does not 
disclose building a dual walled containment section. 
The Newburger patent discloses an oil tanker apparatus having an inner 
cargo carrying bladder to receive oil therein and being protected on 
various sides by buffer bladders which can contain pressurized air or 
water as ballast therein. 
The Goldbach U.S. Pat. No. 5,520,131 patent discloses the use of a 
dual-hulled tanker vessel and utilizing variations in pressure achieved by 
the specific gravity of oil versus sea water to provide for the movement 
of the ruptured oil to an acceptable level therein. 
The Lapo et al patent discloses a leakproof oil super-tanker which is for 
to stop or impede the spilling of liquid oil cargo from a damaged hull of 
a water traveling vessel. This structure is used as a mechanical type 
liner structure having a protective layer mounted between an outer rigid 
hull and having an inner flexible layer therein with a wire mesh to add to 
its strength and resistance to puncture during a collision. 
The Sikora et al patent discloses a hybrid framing system for vessels which 
teaches a double-hulled vessel but has complex framing systems to protect 
an inner one of cargo carrying areas and is not deemed pertinent to your 
invention. 
PREFERRED EMBODIMENT OF THE INVENTION 
In one preferred embodiment of this invention, an oil tanker hull assembly 
and method of operation is operable to prevent oil spillage in case of 
accidental hull rupture. This invention is related to the new, modern 
super capacity oil tanker ships which can be constructed with the oil 
tanker hull assembly of this invention. 
The oil tanker hull assembly includes 1) an inner main tank oil cargo 
assembly operable to receive, support, and convey, a primary oil cargo 
therein; and 2) an outer hull tank oil cargo assembly to be constructed in 
compartmental units or bulkheads and enclosing and surrounding the inner 
main tank oil cargo assembly. 
In the case of an accident which could be the hitting of a reef or an 
iceberg, the outer hull tank oil cargo assembly will be ruptured which 
forces a secondary oil cargo therein to move upwardly due to pressure 
differentials and density differentials between an oil cargo and sea water 
to prevent spillage therefrom into surrounding sea water. 
The inner main tank oil cargo assembly is provided with an arcuate bottom 
wall member which is integral with spaced parallel side wall members and 
enclosure end wall members. 
The inner main tank oil cargo assembly provides a large reservoir having an 
immense primary oil cargo contained therein. An upper main tank oil cargo 
line is substantially above sea level and being spaced inwardly from an 
outer side wall member of the outer hull tank oil cargo assembly. Any 
outer hull tank breach or rupture on an outer wall member would not 
penetrate the side wall member into the inner main tank oil cargo 
assembly. 
The outer hull tank oil cargo assembly is provided with compartment 
bulkhead assemblies operable to provide a plurality of adjacent spaced 
compartmentalized hull tanks extended throughout the outer length and 
periphery of the inner main tank oil cargo assembly. 
Each compartment bulkhead assembly is provided with a bulkhead bottom wall 
member and integral bulkhead side wall members and formed with an outer 
wall member to form the compartmentalized hull tanks. 
The bulkhead side wall members each have a top surface therein preferably 
at a height equal to an outer sea level to a floating oil tanker ship when 
the main tank and all of the hull tanks are filled to predetermined, 
calculated capacity. 
Each of the compartmentalized hull tanks are separated by the compartment 
bulkhead assemblies and, during use, are filled with oil up to a hull tank 
oil cargo line. The hull tank oil cargo line is substantially below the 
top surface of the bulkhead side wall members which is substantially 
aligned with the sea level or exterior water line on the oil tanker ship 
for reasons to be explained. 
This invention involves various known principles as to use of negative 
pressure on the inside of the hull tank oil cargo assemblies relative to 
the pressure of sea water on an outside of subject compartmentalized hull 
tanks. 
As shown in FIG. 3, the inner main tank oil cargo assembly is filled with 
the primary oil cargo and having a main tank oil cargo line therein 
substantially elevated from the sea level line. The outer hull tank oil 
cargo assembly is filled with oil cargo to the hull tank oil cargo line 
which is below the sea level line. 
In the method of operation, the main tank and the hull tanks are filled 
concurrently with oil cargo in such a manner so as to equalize pressures 
therein between the various compartment bulkhead assemblies relative to 
the outer wall member and inner wall member. Concurrent and controlled 
loading of the oil cargo assures that pressure being equalized can save 
construction costs as designing the spaced compartment bulkhead assemblies 
of a minimum required thickness plus leaving as much area as possible to 
carry the oil cargo. 
The oil tanker ship is filled with its' oil cargo as noted in FIG. 3 having 
1) the various lines noted therein wherein the sea level line is equal to 
the top surfaces of the bulkhead side wall members; 2) the main tank oil 
cargo line is filled to capacity having an upper maximum level therein; 
and 3) the hull tank oil cargo line is shown as below the sea level line. 
On rupture of the hull tank by a hull tank breach or failure, as noted in 
FIG. 4, due to pressure differential and density of the sea water relative 
to the oil cargo, the sea water would then rush through the hull tank 
breach into the compartmentalized hull tank that has been ruptured. This 
then forces the lighter density oil cargo upwardly therein so that it will 
eventually rise above the top surfaces of the adjacent bulkhead side wall 
members and flow to adjacent ones of the compartmentalized hull tanks. 
This will eventually equalize itself as shown in FIGS. 4 and 6 so that the 
sea water, which has rushed inwardly to take the place of the oil cargo in 
the ruptured compartmentalized hull tank, forces the oil upwardly and over 
the top surfaces of the bulkhead side wall members into adjoining adjacent 
ones of the compartmentalized hull tanks. 
Due to the pressurized difference in lighter weight of the oil cargo, this 
would prevent any oil cargo from moving outwardly through the hull tank 
breach and, thus, prevents contamination of the adjacent sea water. 
OBJECTS OF THE INVENTION 
One object of this invention is to provide an oil tanker hull assembly and 
method of operation which can be constructed with modem super capacity oil 
tanker ships having 1) an inner main tank oil cargo assembly adapted to 
receive, support, and convey a primary oil cargo; and 2) an outer hull 
tank oil cargo assembly provided with a plurality of spaced compartment 
bulkhead assemblies to be divided into a plurality of compartmentalized 
hull tanks, each to convey a secondary oil cargo therein and operable to 
prevent an oil spill into the adjacent sea water on a hull tank breach or 
failure of the respective compartmentalized hull tanks. 
Another object of this invention is to provide an oil tanker hull assembly 
and method of operation having 1) an inner main tank oil cargo assembly to 
receive, support, and convey a primary oil cargo; and 2) an outer hull 
tank oil cargo assembly having a plurality of spaced compartmentalized 
hull tanks, each provided with a secondary oil cargo therein; and 3) each 
of the compartmentalized hull tanks are independently operable on being 
breached to provide movement of the secondary oil cargo therein into 
adjacent ones of the compartmentalized hull tanks as to remain contained 
within the oil tanker ship and prevent any oil cargo from being released 
into the surrounding sea water. 
One other object of this invention is to provide an oil tanker hull 
assembly and method of operation operable to prevent oil spillage in case 
of accidental hull rupture having 1) an inner main tank oil cargo assembly 
to receive, support, and convey a primary oil cargo; and 2) an outer hull 
tank oil cargo assembly mounted about the outer periphery of the inner 
main tank oil cargo assembly and having compartmentalized hull tanks, each 
compartmentalized hull tank independently operable on being breached to 
use a combination of negative pressures on the inside of the hull tanks 
relative pressure of the sea water outside of the hull tanks and using the 
advantage of force of liquid displacement due to the sea water having a 
greater density than the oil cargo so as to force the same upwardly on 
hull tank breach and into adjacent compartmentalized hull tanks. 
A further object of this invention is to provide an oil tanker hull 
assembly and method of operation having method steps 1) to properly add a 
primary oil cargo to a main tank oil cargo assembly; and 2) to properly 
add a secondary oil cargo to an outer hull tank oil cargo assembly and, 
due to proper use of a hull tank oil cargo line being below a sea level 
line, provides for pressure relationships and density characteristics 
between sea water and the oil cargo so as to prevent oil spillage into the 
adjacent sea water on a hull tank breach. 
Still, one other object of this invention is to provide an oil tanker hull 
assembly and method of operation which is economical in construction; 
effective in use; uses basic negative pressure relationships with the 
force of gravity and the force of liquid displacement due to differences 
in density between oil cargo and sea water to prevent oil spillage into 
the adjacent sea water on compartmentalized hull tank ruptures; and 
substantially maintenance free.

The following is a discussion and description of preferred specific 
embodiments of the oil tanker hull assembly and method of operation of 
this invention, such being made with reference to the drawings, whereupon 
the same reference numerals are used to indicate the same or similar parts 
and/or structure. It is to be understood that such discussion and 
description is not to unduly limit the scope of the invention. 
DESCRIPTION OF THE INVENTION 
On referring to the drawings in detail, and in particular to FIG. 1, an oil 
tanker hull assembly and method of operation of this invention, indicated 
generally at 12, includes a large modern super capacity oil tanker ship 
14. 
The oil tanker hull assembly and method of operation 12 is operable to 
prevent oil spillage in case of an accidental hull breach, rupture, or 
failure. This may occur due to hitting a submerged reef formation or an 
iceberg. This invention is operable to prevent oil spill and loss of 
wildlife as occurred in the Valdez ship accident in Alaska. 
The oil tanker hull assembly 12 includes 1) an inner main tank oil cargo 
assembly 18; and 2) an outer hull tank oil cargo assembly 20. 
The inner main tank oil cargo assembly 18 is operable to receive, support 
and convey a primary oil cargo and includes an arcuate bottom wall member 
24 which is integral with spaced parallel side wall members 26 and 
enclosure end wall members 28 at opposite ends thereof. 
The inner main tank oil cargo assembly 18 may be provided with a plurality 
of baffle members to control any splashing or lateral movement of the 
primary oil cargo therein. 
The spaced parallel side wall members 26 form the inside wall of the outer 
hull tank oil cargo assembly 20 as will be explained. 
The outer hull tank oil cargo assembly 20 is operable to receive, support, 
and convey a secondary oil cargo therein in spaced individual 
compartmentalized hull tanks as will be noted. The outer hull tank oil 
cargo assembly 20 includes a plurality of spaced compartment bulkhead 
assemblies 30 used to divide into the spaced compartmentalized hull tanks. 
Each compartment bulkhead assembly 30 cooperates with a bulkhead bottom 
wall member 32 integral with an outer bulkhead side wall member 34 and an 
outer bottom wall member 36 extended about the entire outer periphery of 
the oil tanker ship 14. 
Each compartment bulkhead assembly 30 is provided with a top surface 40 
which is designed to be in horizontal alignment with the sea level 42 
present on the outside of the oil tanker ship 14 when in the fully loaded 
with oil cargo condition. 
It is obvious that the compartment bulkhead assemblies 30 provide a 
plurality of the compartmentalized hull tanks, each one independently 
operable on receiving a hull tank breach or rupture 54 therein (FIG. 4) as 
will be explained. 
In order to understand the method of operation of the oil tanker hull 
assembly 12 of this invention, it is important that we note numerous 
reference points herein which are important as the main principles being 
utilized herein are 1) the use of negative pressures being the oil 
pressure of the secondary oil cargo in the outer hull tank oil cargo 
assembly 20; and 2) the force of liquid disbursement as the sea water 
surrounding the oil tanker ship 14 has a greater density than the 
secondary oil cargo within the outer hull tank oil cargo assembly 20. 
In order to utilize this difference in density and pressures, we need to 
note that there is a sea level line 42 being the exterior water line on 
the oil tanker ship 14. This sea level line 42 is designed so that, when 
the oil tanker ship 14 is fully loaded with the primary oil cargo and the 
secondary oil cargo, the sea level line 42 will be in alignment 
horizontally or at equal height to the top surface 40 of the compartment 
bulkhead assemblies 30 to allow proper operation thereof. 
Also, we have a main tank oil cargo line 44 which is an upper level of the 
primary oil cargo 22 within the inner main tank oil cargo assembly 18. 
This main tank oil cargo line 44 would normally not be altered except for 
different densities of oil product contained therein but so engineered, 
designed, and loaded with an oil cargo 56 so that the sea level line 42 is 
in alignment with the top surface 40. 
There is provided a hull tank oil cargo line 46 which is the normal upper 
limit of the secondary oil cargo which is adapted to be positioned 
substantially below the sea level line 42 and the top surface 40 for 
proper operation on a hull tank breach or rupture 54 as will be explained. 
After a hull tank breach or rupture 54 and on equalization of pressures 
within the breached compartmentalized hull tanks, there will be 
established an upper new hull tank oil cargo line 50 and a new breached 
hull tank lower oil cargo line 48 as will be explained and as shown in 
FIG. 6. 
Additionally, in FIG. 6, we have established new levels for the oil cargo 
56 and sea water 58 within the breached area of the ruptured 
compartmentalized hull tanks. 
USE AND OPERATION OF THE INVENTION 
In the use and operation of the oil tanker hull assembly and method of 
operation 12 of this invention, it is to be noted that the oil cargo is to 
be conveyed in a modem super capacity oil tanker ship 14 as noted in FIG. 
1. 
The oil cargo 56 is to be loaded within the oil tanker ship 14 and in the 
oil tanker hull assembly 12 in a predetermined engineered and controlled 
manner. 
The controlled manner would be to load the inner main tank oil cargo 
assembly 18 and the outer hull tank oil cargo assembly 20 in a controlled 
manner so as to have equalized oil pressures on the opposite sides of the 
compartment bulkhead assemblies 30 and within the inner main tank oil 
cargo assembly 18 so as to equalize pressures therein. The pressures would 
be exerted by the adjacent sea water 58 and affected by the particular sea 
level line 42 and, additionally, the pressure created by the primary oil 
cargo and the secondary oil cargo 29. 
Therefore, the oil cargo 56 is added to the oil tanker hull assembly 12 in 
a controlled, pre-engineered manner until it reaches the fully loaded 
condition as noted in FIG. 3. 
The hull tank oil cargo line 46 is positioned substantially below the sea 
level line 42 which is in alignment with the top surface 40 of the 
compartment bulkhead assemblies 30. This then presents the normal 
condition for transporting the oil cargo 56 from one ship terminal to 
another. 
On referring to FIG. 6, it is noted that on the hull tank breach or rupture 
54 having occurred, the sea water 58 will flow into the breached 
compartmentalized hull tank. This sea water 58 flowing into this ruptured 
compartment would then force the lighter weight oil cargo 56, having less 
density than the sea water 58, would force the secondary oil cargo within 
the ruptured compartmentalized hull tank to flow upwardly and overflow the 
top surface 40 of the compartment bulkhead assemblies 30 and flow into the 
adjacent ones of the compartmentalized hull tanks. 
This pressure differential and density difference between the sea water 58 
and the oil cargo 56 causes the sea water 58 to move upwardly to a 
position below the top surface 40 of the bulkhead side wall members 34. 
This creates a new breached hull tank lower oil cargo line 48 therein as 
noted in FIG. 6. Concurrently, this forms a new breached hull tank upper 
oil cargo line 50 which would be common in all of the compartmentalized 
hull tanks. 
Therefore, it is seen that the oil tanker hull assembly and method of 
operation 12 is operable to use the pressure differential between sea 
level 42 and the secondary oil cargo so that there is no oil spillage into 
the adjacent sea water 58. 
It is obvious that a breach may occur directly at a compartmental bulkhead 
assembly 30 so that adjacent ones of two compartmentalized hull tanks are 
ruptured but this should not present any problem and the pressure 
differential and fluid density differences using the force of gravity and 
force of liquid displacement will operate as previously described to 
prevent any oil spillage into the adjacent sea water 58. 
The oil tanker hull assembly and method of operation of this invention is 
economical to manufacture; automatic in use and operation due to the 
forces of gravity and liquid displacement; and substantially maintenance 
free. 
While the invention has been described in conjunction with preferred 
specific embodiments thereof, it will be understood that this description 
is intended to illustrate and not to limit the scope of the invention, 
which is defined by the following claims: