US3716154A

US3716154A - Process of counteracting a tilting of a ship's hull during loading and unloading of comparatively heavy cargo units and a device to be used in such process

Info

Publication number: US3716154A
Application number: US00112667A
Authority: US
Inventors: L Berg; R Nes
Original assignee: Lund Mohr & Giaever Enger
Current assignee: Ingeniorene Lund Mohr & Giaever Euger no; Lund Mohr & Giaever Enger
Priority date: 1970-02-06
Filing date: 1971-02-04
Publication date: 1973-02-13
Anticipated expiration: 1990-02-13
Also published as: SE372225B; FR2078301A5; ES388034A1; NO128263B; GB1351591A; DE2105170A1; NL7101531A

Abstract

A process to prevent tilting of a ship''s hull during loading and unloading of comparatively heavy cargo units by means of the ship''s own cargo gear, using at least one supporting leg mechanism on board the ship to support the ship against a top face on a quay and using a manometer in said mechanism to control that a positive load is applied continuously in said mechanism against said top face provided mainly by trimming the ballast tanks of the ship. A supporting leg mechanism provided with a manometer and means to adjust the mechanism in relation to the quay level.

Description

United States Patent [191 111 3,716,154 Berg et al. 1 Feb. 13, 1973 [s41 PROCESS OF COUNTERACTING A [56] ,References Cited TILTING OF A SHIP'S HULL DURING LOADING AND UNLOADING OF UNITED STATES PATENTS COMPARATIVELY HEAVY CARGO 3,165,211 1/1965 Ablett et al ..2l4/1 5 R UNITS AND A DEVICE TO BE USED IN FOREIGN PATENTS OR APPLICATIONS SUCH PROCESS 389,553 3/1933 Great BrItaIn ..1 14/125 570,998 2/1933 Germany ..1 14/125 Inventors: Leif Berg, Risskov, Denmark; Ragnar Jonas Nes, Minde, Norway Assignee: lngeniorene Lund, Mohr & Giaever- Euger, Bergen, Norway Filed: Feb. 4, 1971 Appl. No.: 112,667

Foreign Application Priority Data Field of Search..... .2l4/l5 R, 152; ll4/l25, 230

Primary Examiner-Drayton E. Hoffman Assistant Examiner-Frank E. Werner Attrneyl(enyon & Kenyon Reilly Carr & Chapin 7] ABSTRACT A process to prevent tilting of a ships hull during loading and unloading of comparatively heavy cargo units by means of the ships own cargo gear, using at least one supporting leg mechanism on board the ship to support the ship against a top face on a quay and using a manometer in said mechanism to control that a positive load is applied continuously in said mechanism against said top face provided mainly by trimming the ballast tanks of the ship. A supporting leg mechanism provided with a manometer and means to adjust the mechanism in relation to the quay level.

2 Claims, 7 Drawing Figures 79 i l 97 tl/ 26 23 27 /10 71 3 24 a 100 i 70b PATENTEDFEB 13 1975 3.716.154 SHEET 10F 3 w 19 'L j 21 77 20 26 23 27 V70 11 25 INVENTORS LEM- BERG RM AR dorms PROCESS OF COUNTERACTING A TILTING OF A SHIP'S HULL DURING LOADING AND UNLOADING OF COMPARATIVELY HEAVY CARGO UNITS AND A DEVICE TO BE USED IN SUCH PROCESS The present invention relates to a processof counteracting a tilting of a ships hull during the loading and unloading of heavy cargo units.

At present, it is usual to construct special ships for transporting different types of cargo. More and more of the ships now put into service are especially designed for transporting uniform cargo units, such as containers or the like. As a result thereof, a need has arisen for ships which are particularly suitable for transporting heavy and large cargo units, that is, units which previously may have been carried by ordinary liners, but which the container ships of to-day are not designed to carry. Even large ships of ordinary types may have problems in handling comparatively heavy cargo units. It is, however, obvious that the problems in such cases will increase by decreasing the size of the ship. Ships of limited size hitherto have to depend on stationary or floating cranes in case of loading and unloading heavy cargo units, in order to avoid possible tilting of the ships hull during loading and unloading.

In US. Pat. No. 3,165,211 is described a ship,

designed for container transport in which the cargo units may be transported directly on to and on board v the ship by means of a vehicle, via a loading ramp, and

may be loaded and unloaded through lateral openings below the top deck of the ship. In order to prevent a possible tilting of the ships hull, a stabilizing foot plate has been arranged on a ram which may be extended telescopically outwards and downwards from the side of the ship until the foot plate engages a certain supporting surface located in a convenient level below the waterline of the ship. A supporting arrangement of this type is dependent on a sufficiently firm and solid nature .of the supporting surface being present at such quay or other loading or unloading berth.

ln handling heavy cargo units it is essential that the loading and unloading operations are performed under 7 completely controlled conditions, and accordingly a supporting mechanism located below the waterline is not advisable in this respect. In handling heavy cargo units, the load applied to a supporting mechanism of the above-mentioned type will be unduly great, and necessitate solid supporting foundations.

One of the main objects of the present invention is to avoid possible tilting of the ships hull during the loading and unloading operation of heavy cargo units, by means of ships loading gear, so that the ship will be independent of stationary or floating cranes or other local assistance, and without being dependent on special supportingfaces below the water line on a loading or unloading berth.

Another object of the invention is to make it possible to obtain a continuous control and adjustment of the stability of the ship in relation to a quay or the like, during loading and unloading operations while limiting the movements of the ship substantially to vertical movements during loading and unloading.

The present invention embodies a process of counter-acting a possible tilting of the ships hull during loading and unloading of heavy cargo units by means of the ships cargo gear and by means of a supporting leg mechanism which engages a stationary, horizontal surface outside the ship. The process of the invention is characterized by using at least one supporting leg mechanism, which after being swung outwardly from an inoperative position on board the ship and after having engaged a horizontal surface on a quay which is at a variable level above the water-line of the ship, and while stating the load via a manometer on or in the supporting leg mechanism when the mechanism is subjected to an initial load and later on when subsequent stresses are exerted by the cargo unit on the ships cargo gear, is subjected to further controlled load which is regulated mainly by ballast trimming, and in part by mechanical adjustment of the load in the supporting leg mechanism.

The use of a manometer as stated above permits continuous visual control of the load applied to the top face of the quay during loading and unloading operations, and makes it possible to adjust such load within desired limits.

In certain cases, particularly in the handling of socalled medium weight cargo units amounting to for instance a load of 30 tons, it may be sufficient to employ only a single supporting leg mechanism. In other cases, particularly such cases which involve special conditions, such as a local prohibition against heavy load (axle load) on the quay or similar supporting location, may necessitate the employment of two or more supporting leg mechanisms located at a certain distance from each other in order to distribute the load to different locations on the quay. Particularly in case of handling heavy cargo units, but also in case of handling medium weight units, it is preferred to employ two (or more) separately adjustable supporting leg mechanisms, arranged one on each side of the path of movement of the cargo unit during loading and unloading. This involves a particularly favorable distribution of the load on the supporting surface, and a corresponding favorable adjustable load in each of the this possible tilting effect of the ship may be employed to attain a desirable distribution of load on the different supporting leg mechanisms during the movement of the cargo unit.

When two supporting leg mechanisms have a positive load against the quay, the ship is accordingly prevented from tilting longitudinally as well as transversely Such handling of cargo units is of considerable advantage and allows cargo units to be handled with greater safety as compared to usual loading and unloading operations.

The loading and unloading operations of comparatively heavy cargo units require safe and exact handling of the cargo units-with full control of all movements during the whole loading or unloading operation. For this reason, the loading and unloading operation usually requires a considerable amount of time. It is not unusual that such loading or unloading operation of a single cargo unit requires several hours of operation. This means that sufficient time makes it possible to stabilize and trim the ship as may be required. In order to ensure a best possible control of the handling of the cargo unit and of the condition of the ship during actual loading or unloading operations, it may be necessary to make certain adjustments before as well as during the loading or unloading operation, for instance with regard to the load applied to the quay via the individual supporting leg mechanisms. The load on the quay may then be adjusted by means of ballast trimming and by mechanical adjustment of the load in each individual supporting leg mechanism. Without the use of supporting leg mechanisms it is, however, often extremely risky and dangerous to undertake ballast trimming during loading or unloading operations, due to the lack of stability of a ship when handling relatively heavy cargo units. The use of one or more supporting leg mechanisms makes it far safer to carry out effective adjustments by means of ballast trimming and other possible mechanical alterations of the load.

The invention also embodies a device to be used in the process as described above. The device is characterized by a supporting leg mechanism which is mounted pivotably on board the ship in order to be swung from an inoperative position on board the ship to a position extended over the surface of the quay, and by means of a pressure medium cylinder being arranged to maneuver the supporting leg mechanism to a position to engage a supporting surface at a level above the waterline of the ship and hence to apply an initial load via the supporting leg mechanism to the surface of the quay, via a manometer located in the supporting leg mechanism.

As mentioned above, the transference of comparatively heavy cargo units to or from a quay or the like usually amounts to several hours work. This may give rise to special problems during operation, due to the ship being shifted by the tides and longitudinally displaced in relation to the quay, or due to other local movements of the ship in relation to the quay caused by heavy seas or strong winds. Even the load applied to the ship by means of the weight of the cargo unit, or by transferring the load from the ship to the quay, may result in certain vertical or longitudinal displacements of the ship in relation to the quay, especially when heavy cargo units are handled by small ships. In order to obtain sufficient supporting means on the quay or the like to compensate for such displacements, the supporting surface ofa supporting leg in the supporting leg mechanism forms a roller bed to support a roller connected to said supporting leg mechanism.

Further features of the invention will appear from the following description ofa preferred embodiment of the invention, in which:

FIG. I is a transverse section of a-ship supported against the quay by means of a supporting leg mechanism according to the invention, during loading ofa comparatively heavy cargo unit.

FIG. 2 is a fragmentary detail of the supporting leg mechanism, seen in elevation.

FIG. 3 is another fragmentary detail of the supporting leg mechanism, seen in elevation.

FIG. 4 illustrates partly in vertical section, and on a larger scale, the same as that shown in FIG. 3, but viewed at a 90 angle in relation to FIG. 3.

FIG. 5 is a detail of the supporting column of the supporting leg mechanism, shown in vertical section.

FIG. 6 is an alternative embodiment illustrated in an elevation corresponding to FIG. 3.

FIG. 7 is a schematic representation, in sectional plan, of a ship equipped with two supporting leg mechanisms and two derricks.

FIG. 1 illustrates a ship 10 located along a quay 11 and taking on board a cargo unit 12 by means of the ships derrick 13 via a hoisting line 14 driven by a winch 15. The derrick 13 is being topped and lowered by means of a topping line 16 which is driven by a winch 17. For the sake of clarity the guys arrangement for rotating the derrick around a vertical axis is not shown. This arrangement may be of any ordinary type.

In the position of the cargo unit 12 as shown in FIG. 1, the cargo unit exerts a tilting moment on the ship via the derrick 13, the topping line 16, and the mast 18. A corresponding tilting movement also occurs if a crane arrangement is used instead of the derrick arrangement shown. This undesirable tilting moment arises in case a rotary crane is used as well as in case a portal crane is used with the only difference that a portal crane imparts a rectilinear movement to the cargo, whereas rotary cranes and derricks impart an arc-shaped movement. The object of the present invention is to neutralize the effect of such tilting moments upon loading and unloading of a ship by means of the ships own cargo gear. According to the invention a process is proposed using a supporting leg mechanism which provides a support for the ship against the horizontal surface of a quay or the like, in order to prevent any possible tilting ofthe ships hull.

In FIG. 1 is illustrated a

starboard side tank

10a, 21 port side tank 10b, a starboard bottom tank and a port bottom tank 10d. In practice several such side and bottom tanks may be located in rows along the ship. The tanks may be regulated separately so that various parts of the ship may be trimmed in a known manner, as the need thereto arises.

In FIG. 1 is further illustrated a supporting leg mechanism incorporating a vertical, pivotally attached supporting column 19 of which the lower end is attached to the deck 20 by means of a pivot bearing and thrust bearing, the upper end being supported by a bracket 21, in a pivot bearing 21a (FIG. 5). The one end of a pressure transferring supporting leg 23 is pivotable at a location 22, around a horizontal shaft at the top of the column 19, whereas the one end of a tension transferring supporting leg 25 is pivotable at a location 24, around a horizontal shaft at the lower end of the column. The opposite end of the supporting leg 25 is linked to the supporting leg 23 at a location 26, as described in detail in the following. The projecting end of the supporting leg 25 carries a support roller 27 which rests on a plate-shaped roller bed 28 the lower side of which is supported by a pressure medium cylinder 29 in a supporting foot 30 which rests against the horizontal surface of the quay 11.

FIG. 2 shows further details ofa first embodiment for pivoting the supporting leg mechanism in a vertical plane. One end of a pressure medium cylinder 31 is pivotable at a location 32, in relation to the supporting leg 25 at its pivot bearing 24, whereas a piston rod 33 of said cylinder 31 is pivoted at the upper end of a link arm 34 which is pivoted in the supporting leg 25 at a location 35. The link arm 34 is by means of a chain 36 or the like connected to the supporting column 19 at a location 37. The chain 36 and the leg 25, respectively the column 19 and the link arm 34, form two pairs of opposing tension elements in a tension parallelogram. By means of the cylinder 31 and the piston rod 33, the leg 25 is pivotable in relation to the column 19, around a horizontal shaft 24. The connection between the leg 25 and the leg 23 is so arranged that when the leg 25 is pivoted, it will slide along the supporting leg 23 and force the leg 23 to pivot into a desired inclination in relation to the quay.

FIG. 3 shows two parallel pressure

medium conduits

29a and 29b, which are located along the leg 25 and communicate with opposite ends of the pressure medium cylinder 29. A manometer 29d communicates with the cylinder 29 via a branch conduit 29c and is shown beside the supporting foot 30 but can in practice be located at any suitable place on the supporting leg mechanism or on board the ship. FIG. 2 shows a corresponding manometer 31a located in a branch conduit 3112 from the cylinder 31. The pressure medium conduits to the cylinder 31 are not further shown in FIG. 2, but can be connected to the same pressure medium source as

conduits

29a and 29b in FIG. 3.

FIG. 3 shows the link connection between the supporting leg- 23 and the leg 25. The supporting leg 23 and the leg 25 are constructed from tubes of square section, and through-going holes are drilled with suitable intervals in the supporting leg 23, as indicated by dotted lines 38. At 39 is illustrated a guide piece 39 which is designed to slide along the supporting leg 23. On the top of the guide piece 39 is illustrated a locking bolt 40 with a handle section 41 projecting laterally on two opposite sides thereof and resting in guide grooves 420 on the top of two brackets 42 (not shown in FIG. 3) located at two opposite sides of and attached to the guide piece 39. The locking bolt 40 is arranged to be released by first being lifted up above the guide grooves 42a and then turned 90 about its longitudinal axis in order to be lowered through holes 39a in the guide piece 39 and corresponding holes 38 in the supporting leg 23. In order to align the holes 39 in the supporting leg 23 with the holes 39a in the guide piece 39, during sliding of the latter outwards along the supporting leg 23 towards a desired position on the leg 23 and correspondingly pivoting the leg 25 and the leg 23, it is possible, as shown in FIG. 3, to make use of a stopping bolt 43, which in advance has been placed in position in a set of holes 38 on the supporting leg 23 at a suitable distance from a second set of holes 38 into which the locking bolt 40 is to be lowered. The stopping bolt 43 may form a direct contact with the guide piece 39 in order to locate the guide piece in the exact predetermined position on the supporting leg 23.

In the embodiment illustrated in FIG. 3 the roller bed 28 is suspended by chains 44 from the leg 25 at a suitable distance from the supporting roller,27, and the roller bed 28 is correspondingly connected to the supporting foot 30 by means of chains 45. In FIG. 3 is illustrated the piston rod in the pressure medium cylinder 29, which is incorporated in the supporting foot 30, and is illustrated in extended position in order that the supporting foot 30 the suspended by the chains 45'from the roller bed 28. The supporting foot is arranged to make contact with the supporting surface on the quay or the like as the supporting leg mechanism is swung outwardly via the pressure medium cylinder 31. The supporting leg mechanism is pivotable about a vertical shaft by means of a rotary piston cylinder (not shown) or by means of a sliding piston cylinder which for instance may be connected to the supporting column 19 at an attachment location 19a (FIG. 5). After the supporting foot has engaged with the surface of the quay,

- the pressure in the cylinder 31 may be relieved, in

order that the supporting roller 27 may be lowered onto the roller bed 28. In case the holes 39a in the guide piece 39 are not exactly in alignment with the holes 38 in the supporting leg 23 after the roller 27 has been lowered onto the roller bed 28, an adjustment is possible by means of the pressure medium cylinder 29 in the supporting foot 30 in order to adjust the level of the roller bed to the level of the supporting roller 27. This operation may take place as soon as the guide piece 39 is brought in contact with a stopping bolt 43. Alternatively, the chains 45 may be unhooked to permit the supporting foot to be further lifted above the position as shown in FIG. 3.

FIG. 6 shows an alternative embodiment to that illustrated in FIGS. 2 and 3. Instead of the illustrated cylinder 31 being located on the leg 25, cylinders 46 may be attached to the supporting leg 23, one on each side of the supporting leg 23. The figure, however, only shows one cylinder, the other being hidden behind the one illustrated. Pistons 47 of the pressure medium cylinders 46 are connected to the guide piece 39 at the link point 26 of the leg 25. By means of the cylinders 46 the relative position of the supporting leg 23 and leg 25 may be adjusted, and it is also possible, if considered necessary, to supplement the contact between the supporting foot and the supporting surface of the quay by applying a positive load to the supporting surface (via the guide piece 39, the leg 25 against the supporting roller 27, the roller bed 28, the cylinder 29 and the supporting foot 30, as shown in FIG. 3). A locking bolt 40 is also shown in FIG. 6, and is used in a manner corresponding to that in FIG. 3. In FIG. 5, the locking bolt 40 is located eccentric in relation to the link point 26, whereas the locking bolt 40, according to FIG. 3, is located concentrically in relation to the link point 26. In the embodiment shown in FIG. 6 the locking bolt 40 and the stopping bolt 43 can be omitted, and the guide piece 39 may be adjusted in a desired position before as well as during loading and unloading operations. A supporting foot 30 corresponding to that shown in FIG. 3

or any other suitable means of contact can be used. A

manometer 46a is connected to the pressure medium line of the cylinder 46.

In the following some examples of various methods and devices according to the invention will be described, and reference is had to FIGS. 1 and 7. In FIG, 7 the ship is shown with its port side located along the quay 11, corresponding to what is illustrated in FIG. 1. The ship illustrated is shown with two supporting

leg mechanisms

50, 51 arranged one at each end of the ship. Two

derricks

52, 53 are arranged in the midships vertical plane. Although not specially shown, altemative cargo gear can be used, such as rotary cranes, portal cranes or the like. It is also possible to use derricks or rotary cranes arranged at one side of the ship.

A cargo unit of 40 tons is to be loaded from a position A outside the ship on the port side thereof to a position B on board the ship. It is assumed that all the

ships tanks 10a

10b, 10c and 10d are loaded at the start of the operation, and that the buoyancy is equal to a load D, as indicated by an arrow in FIG. 1.

Primarily, supporting

leg mechanisms

50, 51 are extended until they engage the top face of the quay 11 on starboard side, making contact at a distance of 6 m from the corresponding side of the ship (at a distance of 21 m from position A). Thereupon a load of 40 tons is discharged gradually from the port side tank 10b and a load of 50 tons is discharged from the port bottom tank 10d. This results in an initial load amounting totally to 45 tons being applied to the top face of the quay 11, via the supporting legs before the loading operation commences.

The loading operation is started by hoisting the cargo unit via the aft derrick 52 alone to a level of for instance l m above the top deck of the ship. The buoyancy is calculated to amount to a load of D86 tons.

The cargo unit is then swung to a position B and lowered into a desired position on board the ship. Hence the load on the starboard side tank a is discharged to an extent corresponding to the remaining amount of load in the port side tank 10b and at last the port bottom tank 10d is filled completely. The load on the supporting leg mechanism is released accordingly, and the supporting legs may be retracted to their starting position.

EXAMPLE 2 A cargo unit of 40 tons is to be unloaded direct from the position 13 on board the ship to a position C at a distance of4 meters from starboard side of the ship, on to the top face of the quay 11. It is assumed that the

bottom tanks

10c and 10d are completely filled when the operation is started, and that the

side tanks

10a and 10b ofthe ship each contains tons of ballast.

Primarily, the supporting

leg mechanisms

50, 51 are extended until they engage the top face of the quay 11 on starboard side of the ship making contact therewith at a distance of 6 m from the corresponding side of the ship. Thereupon a load of 50 tons are discharged from the port bottom tank 10d to the starboard tank 10a. An initial load is now being applied to the top face of the quay via the supporting

leg mechanisms

50, 51.

The cargo unit is then hoisted by means of the aft derrick 52 alone to a level of 10 m above the top deck of the ship and is later on swung into a position just above the side of the ship (at a distance of 4 m from position C). The buoyancy is calculated to amount to a load of D135 tons. The total pressure applied to the top face of the quay via the supporting leg mechanisms 50,

51 is calculated to amount to a load of 60 tons, i.e. a

load of 40 tons on the aft leg mechanism 50 and a load of 20 tons on the forward leg mechanisms 51. The

tanks

10b and 10d are now filled to the same level as of the

tanks

10a and 10c. In this position the buoyancy is calculated to amount to a load of D+2O tons, whereas the total load applied to the supporting leg mechanisms is calculated to an amount of 20 tons.

Later on the cargo unit is swung outside the ship's side to the position C, and the total load applied to the top face of the quay via said two supporting leg mechanisms is amounting to 33.4 tons, whereas the buoyancy is calculated to amount to a load of D+6.6 tons.

Finally the cargo unit is lowered onto the top face of the quay 11, and the supporting leg mechanisms may be disengaged and retracted.

EXAMPLE 3 A cargo unit the load of which amounts to 75 tons is to be loaded from position C on the quay 11 at a distance of 4 meters from the starboard side of the ship, to position B on board the ship. It is assumed that the

ship tanks 10a

10b, 10c and 10d are completely filled as the operation starts, and that the buoyancy is equal to a load D.

Primarily, the supporting

leg mechanisms

50, 51 are extended until they engage the top face of the quay 11 on the starboard side of the ship. The cargo unit is then hoisted by the derrick 52 alone. The buoyancy is calculated to amount to a load of D+12.4 tons, whereas the total load on the supporting

leg mechanisms

50, 51 is calculated to amount to 62.5 tons, i.e. a load of 40 tons on the aft leg mechanism 50 and a load of 22.5 tons on the forward leg mechanism.

The cargo unit is lifted to a level of9 m above the top deck of the ship and is swung inwardly above the deck to a position at a distance of 5 m from the side of the ship. Thereupon a load of tons of ballast are discharged from the port side tank 10b.

The cargo unit is later on swung further inwardly above the deck to a position just above position B and is lowered into position on board the ship. The starboard side tank 10a is then completely discharged of ballast and the supporting leg mechanisms may be retracted.

The examples described above illustrate loading of cargo units amounting to a load of tons in a single derrick. ln case both

derricks

52, 53 are employed simultaneously cargo units amounting to a load of I50 tons may be handled in approximately corresponding manner. In the examples described above two supporting leg mechanisms were used, but one single mechanism may be sufficient for handling cargo units with a load of 20-30 tons.

In the examples above the trimming operation of the ship is described to be solved solely by ballast trimming in certain fixed positions of the cargo unit during loading and unloading, but the ship may of course be trimmed more or less continuously, or in several other selected positions of the cargo unit.

By means of ballast trimming a desired load may be applied to the supporting surface on the quay via the supporting leg mechanisms, thus preventing tilting of the ships hull during loading and unloading. ln case two supporting leg mechanisms are used to engage the supporting surface at different times during loading and unloading operations, the load may be distributed in a controlled manner by means of a respective supporting leg. This may also be attained by regulating the filling and the discharge of the various tanks forward and aft on board the ship or, if desired, by using corresponding pressure medium cylinders to apply a different initial load to a respective one of the two supporting leg mechanisms. It will similarly be possible, by means of the pressure medium cylinders of each supporting leg mechanism, to apply an extra load to the supporting surface of the quay in order to stabilize the ship in a desired position. It is also possible to combine in different other ways the adjustments of the supporting leg mechanisms with the adjustment by ballast trimming all according to what may be required during practical loading and unloading operations.

What we claim is:

l. A process of counteracting a tilting ofa ship's hull during loading and unloading of heavy cargo units by means of the ship's cargo gear and'by means of a supporting leg mechanism which engages a stationary, horizontal supporting surface outside the ship, characterized by using at least one adjustable supporting leg mechanism, which'after being swung outwardly from an inoperative position on board the ship and after having engaged a horizontal surface on a quay which is at a variable level above the waterline of the ship, and while stating the .load via a manometer on or in the supporting leg mechanism when said mechanism is subjected to an initial load and later on when subsequent stresses are exerted by the cargo unit on the ships cargo gear, is subjected to a further controlled load which is regulated mainly by ballast trimming, and in part by mechanical adjustment of the load in the supporting leg mechanism.

2. A process in accordance with claim 1, characterized by the use of two separately adjustable supporting leg mechanisms, placed one on each side of the path of movement followed by the cargo during loading and unloading.

Claims

1. A process of counteracting a tilting of a ship''s hull during loading and unloading of heavy cargo units by means of the ship''s cargo gear and by means of a supporting leg mechanism which engages a stationary, horizontal supporting surface outside the ship, characterized by using at least one adjustable supporting leg mechanism, which after being swung outwardly from an inoperative position on board the ship and after having engaged a horizontal surface on a quay which is at a variable level above the waterline of the ship, and while stating the load via a manometer on or in the supporting leg mechanism when said mechanism is subjected to an initial load and later on when subsequent stresses are exerted by the cargo unit on the ship''s cargo gear, is subjected to a further controlled load which is regulated mainly by ballast trimming, and in part by mechanical adjustment of the load in the supporting leg mechanism.