DE1277059B - Device to compensate for static heeling and / or bow and stern heaviness on a liquid gas ship - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY GERMAN 4S09TWL PATENT OFFICE

EDITORIAL

Int. Cl .:

Number:
File number:
Registration date:
Display day:

B 63b

German class: 65a2-30

P 12 77 059.1-22 (P 32515)

3rd September 1963

5th September 1968

The invention relates to a device for compensating for static heeling and / or bow and Stern-heaviness on a liquefied gas ship. It is common knowledge that nuisances occur on tankers balance by pumping cargo liquid into the appropriate tanks. Is the Cargo liquid a liquefied gas, which is present as a gas in the normal state, then join Effects of heat on the tanks, e.g. B. due to solar radiation, high pressure changes in the tanks as the liquefied gas contained therein evaporates.

An annoyance due to the difference in density between vapor and liquid To avoid this, a central gas space is provided in a known manner (US Pat. No. 2,724,357), the ends of which are filled with liquid so that the liquid does not come to one end and that Gas flows to the other end. The mass introduced into such a tank during loading remains until for unloading in the same tank. This has the disadvantage that the tank takes up the pressure must absorb through the evaporating gas, which leads to a complex and heavy construction that is also expensive, leads and reduces the payload capacity of the ship.

It is known to reduce the pressure in a liquefied gas tank by having a Cooling is provided. Such a re-cooling is z. B. in a known manner (Marine Engineering / Log, August 1961, pp. 61, 62) used in the discharge of liquid methane, the separated vapor is liquefied after a cooling process and fed to the same cargo tank. Cooling can also be carried out at sea by adding steam withdrawn from a tank in a known manner after a cold process, d. H. Compress, condense, throttle, recooled (U.S. Patent 2,550,886) and supplied to the same tank as a liquid. The recooling can also be achieved by giving off heat from the steam to a cooling medium in its evaporator part an external, closed circuit, the liquefied vapor in turn in the same tank (U.S. Patent 2,959,928, British Patent 895,663).

In such arrangements, the pressure in the tank is kept low, but it is high Energy required for the recooling, which in turn leads to higher costs. A compensation of annoyance in such arrangements can only be made by pumping.

Device to compensate for static
Heel and / or bow and
Stern-heaviness on a liquefied gas ship

Applicant:

Phillips Petroleum Company,
Bartlesville, OkIa. (V. St. A.)

Representative:

Dr. F. Zumstein, Dr. E. Assmann

and Dr. R. Koenigsberger, patent attorneys,

8000 Munich 2, Bräuhausstr. 4th

Named as inventor:
Leonard Price Meade,
Bartlesville, OkIa. (V. St. A.)

Claimed priority:
V. St. v. America September 4th 1962
(221 049)

Now becomes a liquefied gas ship, the cargo tanks of which are connected to each other by pressure equalization lines stand, on a straight course, illuminated by the sun on one side, this is the effect of the one-sided heat radiation a stronger evaporation of the liquefied gas on the exposed to this irradiation Page. The steam flows through the equalization lines into those on the cooler side of the ship located tanks and partially condenses there. Due to the possibility of pressure equalization you can the tanks can be designed for a lower pressure, and the cooling system can be less expensive are executed. However, static occurs due to the accumulation of liquid on the cool side of the ship Heels or bow or stern heaviness, which are eliminated by pumping the liquid gas have to.

The object of the present invention is now to recirculate the recooled To set up liquid gas quantities on a liquid gas ship in such a way that a possible static Heel or a bow or stern heaviness or at the same time the heeling and the bow or stern heaviness of the ship can be counteracted.

809 599/53

3 4

This is achieved in that above the one part of the liquid located therein. Of the Cargo tanks a transverse and / or fore and aft liquid level tank 31 has a through the stretching distribution tank for the reverse flow control valve 32 regulated outlet, which liquid gas quantities vaporized in the cargo tanks is in turn actuated by the float 33, is arranged, the ends of which with the on each 5 This moves the flow control valve 32 to the open to the transverse and / or fore and aft opposite outlet when in the liquid side of the ship Arranged cargo tank by inclined level tank located liquid via a front piping are connected. given level rises and closes the outlet,

Advantageously, if the liquid is below the specified level in the steam rooms Cargo tanks arranged venturi tubes into which the io falls. With proper cooling by the condenser

Lines from the distribution tank axially 23, the liquid level tank 31 is soon flooded,

flow out. the flow control valve 32 opens, and the liquid

It is particularly expedient for a liquid and / or the vapor to flow through it level tank in the supply line to the distribution tank, flow control valve 32 and line 34 in one a flow control valve in this line downstream 15 distribution tank 36, which is in its larger from the liquid level tank and a floating dimension extends transversely and parallel to the mer to be provided in the liquid level tank, the ship's breadth is arranged and above the loading area increasing liquid the flow control valve tanks 8 and 11 is located. The slope of the liquid opens and it closes when the liquid drops. levels 37 in the liquid level tank 36 depends on the

Embodiments of the invention are in the 20 degree of heeling or listing of the ship Drawing shown and are shown below, with the liquid closer in the present case described. level extends so that on the port side

Fig. 1 shows schematically a statically heeling of the distribution container 36 more liquid on the ship with one extending fore and aft. The port side of the distribution vessel 36 Port and starboard tanks in cross section at 25 are connected to the loading spring via an inclined pipe 38 device according to the invention for compensating tank 11 connected on the starboard side while the heel; the starboard side of the distribution vessel 36 in

Fig. 2 shows schematically a ship with a similar way to the cargo tank8 via a ge

transversely extending bow and stern cargo tank in inclined pipeline 39 is connected. As shown,

Longitudinal section through the center of the ship with the invention, the main part of the liquid is with the level

proper device for balancing the bow 37 through the inclined pipe 38 in the loading

and stern heaviness; 'tank 11 withdrawn, and only a smaller part or

Fig. 3 shows schematically a ship with two only slightly steam flowing through the inclined fore and aft one behind the other arranged starboard pipeline 39 into the cargo tank 8 on the port and port cargo tanks viewed from above with the 35 side. As a result, the cargo tank 11 Device according to the invention for balancing a liquid collects and so the level of the liquid static heeling and / or bow- or stern-heavy 12 increases, so that this rises to the level of the liquid, speed 9 in cargo tank 8 is approaching. It also vaporizes

Fig. 1 shows a tanker 6 in section, with liquid 9 in the cargo tank 8 in the vapor space 13 which one looks in the bow direction, that in the water 7 40 and is discharged to the compressor 21,
heels to port, since the port cargo tank 8 If more liquid 9 is withdrawn from the vapor space 13 of the cargo tank 11 than the starboard cargo tank 11, some liquid 12 will be contained at the same time. The liquid vapor shown from the vapor space 41 of the cargo tank 11 division can be based on the fact that the heat irradiated through the line 42, the valve 43 and the valve from the sun more to the cargo tank 45 44 into the vapor space 46 in the collecting tank 18 , 11 is directed at the cargo tank 8, while the one from which it travels through the line 19 to the Kom-ship on a fixed course and the blackmailer 21 is withdrawn. Since the lines 17 according to the invention device is not yet in operation. and 44 through the steam space 46 in connection

The level compensation is achieved by standing steam, the pressure in the steam chambers 13 and

out of the vapor space 13 of the cargo tank 8 via the 50 41. Since the valves 47, 48,49,51 and

Line 14, the valve 16, the line 17, the 52 during this process for liquid

Collecting tank 18 and steam from the steam space 41 distribution for the heel reduction.

of the cargo tank 11 through the line 42, the valve is closed, the lines 17 and 44 with

43, the line 44, the collecting tank 18 connected in the grain of the line 19, and the collecting tank 18

pressor 21 via line 19 through its suction 55 becomes only part of line 19, d. h., he

effect is led. The compressor 21 is unnecessary if it is not used for loading and unloading

miert the steam and pushes it through the line just like the valve 53, its position during

22 into the capacitor 23, which is insignificant due to any change in the load compensation

addable cooling fluid 24, e.g. B. air or water 7, would.

is cooled by the condenser 23 with a 60 Fig. 2 shows a ship 6, which only a front Pump is promoted. Part of the compressed cargo tank 80 and a rear LBdBtBUkS (K beDampfes condensed from line 22, condensate is seated. The distribution container 36 is similar and residual steam flowing through valve 26 with the ship's axis aligned to or around the bow balance the liquid phase through the line 27 and the stern heaviness. The steam flows from vapor phase through line 28 into the 65 cargo tanks 80 and 80 'into lines 82 and Chamber 29 of the liquid level tank 31 flows. 82 'and via line 83 into the compressor 21, As the pressure rises and the temperature falls, it is condensed and then condensed into one the vapor in the chamber 29 and forms sator 23 to condense, from where the liquid

Claims (3)

5 6 and / or the steam via a valve 32 and the liquid pressure located in the pump 63 In line 34 back into the distribution container 36, the pump 63 runs full of liquid and does not leave any be guided. The liquid in which vapor formation in the liquid occurs below, is not lying Part of the distribution container 36 flows to depending on the level of the liquid 9 in the loading dem Cargo tank 80 or 80 'via the inclined tube 5 tank 8 and the liquid 12 in the cargo tank 11. The line 81 or 81 'back, depending on which pump 63 is advantageously above the The tank is currently the higher one. Ob- the bottom of the cargo tanks 8 and 11 arranged because there it is not shown in the other figures, through the cargo tanks as low as possible in the ship a line 82 'can usually be arranged with an over-, resulting in a larger stable pressure valve 84 provided that at a done for it and greater resistance against occurring © suitable place has a connection to the atmosphere. Annoyance leads. However, it will still be full However, steam can also convey through the throttle, if the pump is even above the cargo tanks 8 valve 85 and the fuel suction line 86 for one and 11 is arranged. Internal combustion engine 87 with exhaust pipe 88 discharged During filling, the pump 63 pumps be pulled. The motor 87 can e.g. B. the ship 15 liquid from the bottom of the collection tank 18, and Drive screw 89. the compressor 21 removes the steam 18 via the According to FIG. 3 the ship 6 has four cargo tanks 8,11, line 19. Since this steam is not in the line 8 ', 11', which is to condense at the bow and stern, port and control 22, the valve 26 is closed are arranged on the board. The distribution tank 36 has and the valve 48 is open, whereby the condenser thereby square cross-section, and the liquid 20 23 and the flow control valve 32 through the too runs from the lowest corner of the distribution container to the distribution container 36 leading line 66 36 into the highest cargo tank through which each can be passed. Since in the distribution container 36 respective inclined pipeline 38, 39, 38 'or 39'. In order for only steam to enter, the liquid 37 becomes fast To simplify the illustration, the in were subtracted through the line 38 into the cargo tank 11, F i g. 3 shown corresponding devices to 25 and steam from the compressor 21 then flows through Removal of steam from cargo tanks 8.11, both inclined pipes 38 and 39 into the 8 ', 1Γ and the compress the steam, condense both cargo tanks 8 and 11. The obtained higher and the liquid to a distribution container 36 to pressure in the vapor spaces 13 and 41 opposite lead, not shown. the pressure in the vapor space 46 presses the liquid The advantages achieved by the invention consist of 30 speed 9 and 12 in the lines 67 and 68 up and in particular that the liquid resulting from heat in the collecting tank 18 via the valve 53, as soon as irradiation on one side of the ship, this valve is open . This enables the appropriate shift to the cooler side of the ship, since the distance for the liquid level above the tanks is maintained by the pump 63 opening into the steam chambers and the evaporation pipes are connected to one another, the liquid in the pump 63 or in the tank is automatically balanced. Since hardly any guide lines 54 and 56 are avoided in the cargo tanks.
When the ship is loaded, the valves 58 and lower strengths can be designed. Furthermore, 59 is closed, and the loading line 69 is connected to the cooling device connected to the system, a conveyor system. The valves 57, 47, not particularly complex and consumes little 40, 49 and 51 are open, and the liquid flows energy. Through the use of Venturi nozzles, by gravity or by pressure in the subsequent to the inclined pipelines, through cargo tanks 8 and 9 via the cargo line 69 and which the recooled liquid or the vapor lines 67 and 68. During loading should be in the Cargo tanks flows back, the valves 16, 43 and 26 are open and the valve 48 achieves a higher cooling capacity. Be closed by using 45. The compressor 21 is operated via a float so that the steam in the steam chambers 13 and the control valve control the cooling under 41 of the cargo tanks 8 and 11 through the lines 14, bypassing the pressure. 17, 42, 44 and 19 discharged into the compressor 21 Due to the device according to the invention for compressed, condensed in the condenser 23 and to compensate for static heeling or the bow liquid through the lines 27, 28 and 34 above or stern heaviness, however, the loading and unloading of the distribution container 36 and the inclined tube loading process of the ship is not made difficult or lines 38 and 39 are returned. Be feasible after slowing down. In order to show that the end of the filling, the valve 57 is closed is not the case, should be on the basis of FIG. 1 of loading and line 69 disconnected from the supply,
and discharge process of the 55 according compensation device for annoyance claims:
the ship seen. During unloading, the valves 16, 43, 26, 47 and _t 1. Device to compensate for static 57 are closed and the valves 48, 49, 51, 52, 58 and heeling and / or bow and stern heaviness to 59 are open. The valve 53 is opened by a liquid 60 a liquefied gas ship, thereby gekennkeitsniveauregelung 61, as soon as the liquid indicates that above the cargo tanks (8, 11, level 62 in the collecting tank 18 below a front 8 ', 11', 80, 80 ' ) a transversely and / or longitudinally determined level falls, and closed as soon as the ship-extending distribution container (36) rises for level above this level. The unloading can take place the reliquefied gas quantities arranged in the cargo tanks (8, 11, 8 'via the lines 54 and 56. A pump 63, preferably a centrifugal pump, is used to discharge 65 11', 80, 80 ') , the ends of which are used with the one on the respective transverse pump. Because of the opposite ship in the line 64 and / or fore and aft in the collecting tank 18 between the liquid level 62 side arranged cargo tank (8, 11, 8 ', 11', 80, 80 ') are connected by inclined pipes (38, 39, 38', 39 ', 81, 81'). 2. Device according to claim 1, characterized in that in the steam compartments (13, 41) of the cargo tanks (8, 11, 8 ' ₅ 11', 80, 80 ') Venturi tubes (72, 73) are arranged, in which the lines open axially from the distribution container (36). 3. Device according to claim 1 or 2, characterized by a liquid level tank (31) in the feed line to the distribution container (36), through a flow control valve (32) in this Line downstream of the liquid level tank (31) and through a float (33) in the liquid level tank (31), which opens the flow control valve (32) when the liquid rises and it closes when the liquid drops. Considered publications: British Patent No. 895,663;
U.S. Patents Nos. 2,550,886, 2,724,357,
2959928;
Marine Engineering / Log, August 1961, pp. 61/62. For this purpose, 1 sheet of drawings 809 599/53 8.68 © Bundesdruckerei Berlin