US3308965A - Marine derrick arrangement - Google Patents

Marine derrick arrangement Download PDF

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US3308965A
US3308965A US521925A US52192566A US3308965A US 3308965 A US3308965 A US 3308965A US 521925 A US521925 A US 521925A US 52192566 A US52192566 A US 52192566A US 3308965 A US3308965 A US 3308965A
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guy
derrick
boom
pendants
pendant
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US521925A
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Kuribayashi Sadatomo
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B63SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63BSHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B27/00Arrangement of ship-based loading or unloading equipment for cargo or passengers
    • B63B27/04Arrangement of ship-based loading or unloading equipment for cargo or passengers of derricks, i.e. employing ships' masts
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66CCRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
    • B66C23/00Cranes comprising essentially a beam, boom, or triangular structure acting as a cantilever and mounted for translatory of swinging movements in vertical or horizontal planes or a combination of such movements, e.g. jib-cranes, derricks, tower cranes
    • B66C23/60Derricks
    • B66C23/605Derricks employing ships' masts

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  • the present invention relates to a marine derrick arrangement, more particularly to a marine derrick arrangement wherein at least one of guy pendants is connected to one end of a topping lift at a point other than that on a derrick boom.
  • each of two guy pendants is connected to an unsupported end of derrick boom and wound around a drum of a single winch with one pendant in a direction opposite to the other, after running through a deflecting sheave located outboard of said winch, with either one of said guy pendants being connected to a topping lift at a point other than that on a derrick boom.
  • the present derrick arrangement comprises three winches, that is, a first winch intended for a topping lift wire which is adapted to control an inclination of the derrick boom, a second winch for lifting cargo, and a third winch which is designed to be used for controlling both guy pendants as a common unit, a derrick boom pivotally mounted on a gooseneck supported indirectly on a deck, a derrick post fixedly mounted on a deck, a pair of guy sheaves located one on each side of the derrick post well aligned therewith, and necessary wirings and blocks including a cargo fall, a topping lift, and guy pendants which are connected to said topping lift at a point other than that on a boom.
  • both guy pendants will be maintained taut at all time by a single winch thereby steadying the derrick boom and reducing vibration of the same during operation.
  • the cargo handling arrangement, particularly those winches therein intended for guy pendants, will be simplified and reduced in number, and time and labour required for operating the whole arrangement and for changing the service arrangement from the starboard to the port side, and vice versa will be greatly reduced.
  • a pair of guy pendants are wound around a pair of identical drums on a common winch in a direction opposite to each other.
  • a paid-out length of one guy pendant from the drum per unit time will be equal to a taken-in length of the other per unit time around another drum, thus keeping the total length of two guy pendants constant at all time as long as they are maintained taut.
  • a locus of points having a constant total distance from two fixed points will delineate an ellipse having a minor axis or shorter diameter equal to twice the length of the derrick boom (see FIG.
  • this slackness is adapted to be absorbed by a topping lift by connecting the guy pendants thereto, so that they are maintained taut at all times.
  • Another object of the present invention is to provide a marine derrick arrangement which is simplified and steadied by using an improved guy means.
  • Still another object of the present invention is to provide a marine derrick means which is easy to handle and which will save man-power greatly in operation in contrast to prior art means.
  • Still another object of the present invention is to provide a marine derrick means the service of which can be changed immediately from the starboard to port side and vice versa without any alteration or change of the arrangement.
  • FIG. 1 is a diagrammatic view showing a preferable embodiment of the marine derrick means according to the present invention
  • FIG. 2 is an enlarged detailed view showing a connection between 'a guy pendant and a topping lift
  • FIG. 3 is a plan view showing a swinging of the derrick boom.
  • FIG. 4 is a diagrammatic View showing another embodi ment of guy pendants according to the present invention.
  • a derrick boom 1 the base 2 of which is pivotably mounted on a hull structure, pad eyes 2, 3 are provided on top of said boom on the both sides thereof, deflecting sheaves 4, 5 are provided on a hull structure on both sides thereof, said sheaves being well aligned with the base of the derrick boom so that both are symmetrically located with reference to said base.
  • a winch 6 is provided for the guy pendants.
  • Guy pendants 8, 9 are wound around said winch 6 in such a manner as to have one guy pendant paid out while the other one is rolled in.
  • Each of the guy pendants 8, 9 is connected to top end of the derrick boom through one of the guy pendant reflecting sheaves 4 or 5 with either one of said guy pendants being connected to a topping lift 10 at a point other than that on the derrick boom.
  • one guy pendant 9 emanates from the guy wire winch 6, runs over two pulleys C and D mounted on the derrick post 11 and over a pulley T which is connected to the topping lift 10, and then connected at 3 to the top end of the boom through the deflecting sheave S.
  • the topping lift 10 which comes down from the top end of the post 11, is connected to said pully T through a deflecting sheave E located on the deck.
  • Said topping lift wire 10 is led to a winding winch 13 intended for said topping lift wire through a topping lift block 12 on top of a derrick.
  • the guy wire winch 6 when the guy wire winch 6 is running in order to swing the derrick boom to the right or to the left, the guy wire will be paid out on one side and rolled on to the same amount in the other side.
  • the guy wire winch 6 will be caused to rotate in a direction to roll in guy pendant wire 9 and to pay out guy pendant wire 8.
  • the guy wire 9 will be rendered taut and pull the derrick boom 1 clockwise.
  • guy wire 8 is more slack, and hence the derrick boom 1 will'be brought back by an amount corresponding to the slacked amount of the guy pendant, thereby causing a vibration of the boom, due to arolling of the ship or a swinging of the cargo.
  • any slackness of the guy pendant 8 will be absorbed by atopping lift which is rendered taut at all time by the weight of the derrick boom 1 and of the suspended cargo. This causes the tension on each guy pendant 8 and 9 to be substantially balanced. At this time, the angle between said derrick post 11 and said derrick boom 1 will be slightly increased but that does not affect the actual operation of the derrick.
  • the topping lift wire will be taken in or paid outby means of a topping lift winch 13 in the same manner as in case of an ordinary derrick arrangement.
  • any slackness of the guy pendants during a swinging operation is absorbed and hence eliminated by the topping lift 10 the tension of both guy pendants is always nearly balanced, and the derrick boom will not be shaked by a rolling of ship or by a swinging of cargo. This assures safe operation of the derrick boom and simultaneously permits no impact to be exerted on any of the guy pendants thereby avoiding the danger of it being broken.
  • topping lift wire 10 which is connected to either one of guy pendants 8, 9, may be run doubly around a block 12 and a block (not shown) on the top end of the boom 1 and then led to the winch 13.
  • a marine derrick arrangement comprising a derrick boom, a pair of guy pendant deflecting sheaves aligned with the base of said derrick boom and located at an equal distance on both sides of said base, a common winch designed for winding two guy pendants, one said guy pendant being wound around said common winch at one end thereof and led through one of said guy pendant deflecting sheaves and then being connected to the top end of saidboom, the other said guy pendant being Wound around said common winch at one end thereof and led through the other of said pair of guy pendant deflecting sheaves and then being connected to the top end of said boom, elevated mounting means, and a topping lift wire extending from a winch means via said mounting means, the top end of said boom, back to said mounting means to a connection with one of said guy pendants.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Ocean & Marine Engineering (AREA)
  • Jib Cranes (AREA)

Description

March 14, 1967 SADATOMO 'KURIBAYASHI 3,308,965
MARINE DERRI CK ARRANGEMENT Filed Jan. 20, 1966 2 Sheets-Sheet 1 z i i /3 WW FIG. 2
INVENTOR. SADATOMO KURIBAYASHI 4 MM M HIS RTT March 14, I967 SADATOMO KURIBAYASHI 3,308,965
MARINE DERRICK ARRANGEMENT I INVENTOR. SADATOMO KURIBAYASHI HIS ATTORNEYS United States Patent Ofiice 3,308,965 Patented Mar. 14, 1967 The present invention relates to a marine derrick arrangement, more particularly to a marine derrick arrangement wherein at least one of guy pendants is connected to one end of a topping lift at a point other than that on a derrick boom.
The U.S. patent application Ser. No. 431,579, filed on Feb. 10, 1965, now Patent No. 3,260,373 discloses a marine derrick arrangement wherein a pair of guy pendants are connected to a topping lift at a point adjacent to an unsupported end of the derrick boom at one end thereof and wound around separate drums of a common winch at the other end thereof after running through a pair of sheaves located on both sides of the winch. The present application constitutes a continuation-in-part application to the above-mentioned application, and discloses a pair of guy pendants that are connected to a topping lift at a point other than that on a derrick boom.
In a prior art derrick arrangement, two guy pendants are usually wound around two different winches with different tension, often with one of them entirely slackened, hence two winches or one winch combined with a counterweight are required for handling both guy pendants and heavy vibration of a derrick boom may occur due to slack guy pendants, causing a serious damage to equipment and cargo.
According to the present invention, each of two guy pendants is connected to an unsupported end of derrick boom and wound around a drum of a single winch with one pendant in a direction opposite to the other, after running through a deflecting sheave located outboard of said winch, with either one of said guy pendants being connected to a topping lift at a point other than that on a derrick boom.
The present derrick arrangement comprises three winches, that is, a first winch intended for a topping lift wire which is adapted to control an inclination of the derrick boom, a second winch for lifting cargo, and a third winch which is designed to be used for controlling both guy pendants as a common unit, a derrick boom pivotally mounted on a gooseneck supported indirectly on a deck, a derrick post fixedly mounted on a deck, a pair of guy sheaves located one on each side of the derrick post well aligned therewith, and necessary wirings and blocks including a cargo fall, a topping lift, and guy pendants which are connected to said topping lift at a point other than that on a boom.
Since the present device is constructed as described hereinabove, both guy pendants will be maintained taut at all time by a single winch thereby steadying the derrick boom and reducing vibration of the same during operation. The cargo handling arrangement, particularly those winches therein intended for guy pendants, will be simplified and reduced in number, and time and labour required for operating the whole arrangement and for changing the service arrangement from the starboard to the port side, and vice versa will be greatly reduced.
As described hereinabove, a pair of guy pendants are wound around a pair of identical drums on a common winch in a direction opposite to each other. Hence, in controlling those guy pendants, a paid-out length of one guy pendant from the drum per unit time will be equal to a taken-in length of the other per unit time around another drum, thus keeping the total length of two guy pendants constant at all time as long as they are maintained taut. Now, a locus of points having a constant total distance from two fixed points will delineate an ellipse having a minor axis or shorter diameter equal to twice the length of the derrick boom (see FIG. 3, curve b), whereas actually a locus of an outer end of the derrick boom will delineate a circle having a diameter equal to the length of the derrick boom (see FIG. 3, curve a). Consequently, except in a position designated by N in FIG. 3, total length of both guy pendants will become excessive, thus causing a slack wire to occur. According to the present invention, this slackness is adapted to be absorbed by a topping lift by connecting the guy pendants thereto, so that they are maintained taut at all times.
It is a primary object of the present invention to provide a marine derrick arrangement which will enable both guy pendants to be maintained equally taut at all times by eliminating a slack wire thereby preventing vibration of the derrick system.
Another object of the present invention is to provide a marine derrick arrangement which is simplified and steadied by using an improved guy means.
Still another object of the present invention is to provide a marine derrick means which is easy to handle and which will save man-power greatly in operation in contrast to prior art means.
Still another object of the present invention is to provide a marine derrick means the service of which can be changed immediately from the starboard to port side and vice versa without any alteration or change of the arrangement.
Other objects and advantages of the present invention will become more apparent from the follownig description taken in connection with the accompanying drawings wherein like reference numerals refer to like parts throughout and in which:
FIG. 1 is a diagrammatic view showing a preferable embodiment of the marine derrick means according to the present invention;
FIG. 2 is an enlarged detailed view showing a connection between 'a guy pendant and a topping lift;
FIG. 3 is a plan view showing a swinging of the derrick boom; and
FIG. 4 is a diagrammatic View showing another embodi ment of guy pendants according to the present invention.
With reference to FIG. 1, there is illustrated a derrick boom 1, the base 2 of which is pivotably mounted on a hull structure, pad eyes 2, 3 are provided on top of said boom on the both sides thereof, deflecting sheaves 4, 5 are provided on a hull structure on both sides thereof, said sheaves being well aligned with the base of the derrick boom so that both are symmetrically located with reference to said base. A winch 6 is provided for the guy pendants. Guy pendants 8, 9 are wound around said winch 6 in such a manner as to have one guy pendant paid out while the other one is rolled in. Each of the guy pendants 8, 9 is connected to top end of the derrick boom through one of the guy pendant reflecting sheaves 4 or 5 with either one of said guy pendants being connected to a topping lift 10 at a point other than that on the derrick boom.
More particularly, as shown in FIGS. 1 and 2, one guy pendant 9 emanates from the guy wire winch 6, runs over two pulleys C and D mounted on the derrick post 11 and over a pulley T which is connected to the topping lift 10, and then connected at 3 to the top end of the boom through the deflecting sheave S. The topping lift 10 which comes down from the top end of the post 11, is connected to said pully T through a deflecting sheave E located on the deck. Said topping lift wire 10 is led to a winding winch 13 intended for said topping lift wire through a topping lift block 12 on top of a derrick.
post 11.
According to the present invention which is constructed as described hereinabove, when the guy wire winch 6 is running in order to swing the derrick boom to the right or to the left, the guy wire will be paid out on one side and rolled on to the same amount in the other side.
Now, for instance, for swinging the derrick boom clockwise in FIG. 3, the guy wire winch 6 will be caused to rotate in a direction to roll in guy pendant wire 9 and to pay out guy pendant wire 8. By running the winch 6, the guy wire 9 will be rendered taut and pull the derrick boom 1 clockwise.
However, if any of the guy pendants is not connected to a topping lift, but merely is secured to the derrick boom 1 at the top end as usual, more swinging of the derrick boom 1 occurs beyond the central position N, guy wire 8 is more slack, and hence the derrick boom 1 will'be brought back by an amount corresponding to the slacked amount of the guy pendant, thereby causing a vibration of the boom, due to arolling of the ship or a swinging of the cargo.
According to the present invention, any slackness of the guy pendant 8 will be absorbed by atopping lift which is rendered taut at all time by the weight of the derrick boom 1 and of the suspended cargo. This causes the tension on each guy pendant 8 and 9 to be substantially balanced. At this time, the angle between said derrick post 11 and said derrick boom 1 will be slightly increased but that does not affect the actual operation of the derrick.
The operation will be carried out in the same manner for swinging the boom counterclockwise.
Now, for changing an angle of inclination of the-derrick boom, the topping lift wire will be taken in or paid outby means of a topping lift winch 13 in the same manner as in case of an ordinary derrick arrangement.-
As described hereina'bove, in the present invention, any slackness of the guy pendants during a swinging operation is absorbed and hence eliminated by the topping lift 10 the tension of both guy pendants is always nearly balanced, and the derrick boom will not be shaked by a rolling of ship or by a swinging of cargo. This assures safe operation of the derrick boom and simultaneously permits no impact to be exerted on any of the guy pendants thereby avoiding the danger of it being broken.-
The accompanying drawings are intended merely for illustrating the principles of, the present invention. topping lift wire 10, which is connected to either one of guy pendants 8, 9, may be run doubly around a block 12 and a block (not shown) on the top end of the boom 1 and then led to the winch 13.
FIG. 4 shows another embodiment of the present invention, wherein both pulleys C and D are mounted on a frame 15 instead of on the derrick post 11, It is noted that a considerable length of the guy wire will be saved =by this arrangement and the possibility of damage to those pulleys will be eliminated since they are well clear of the derrick post and other wires.
When the derrick arrangement according to the present invention is mounted on a small sized ship (about The.
2,000 gross ton) with'its derrick boom located on the center line of the hull structure and with all control levers of three winches (for a topping lift, for guy pendants and for a cargo fall) concentrated at a control platform, the whole derrick arrangement can be actually controlled by a single operator, thus saving a man-power greatly. A changing of service of the system from port to starboard and vice versa will be easily assured without any additional work, illustrating an inherent feature of the present invention.
Although several embodiments of the inventionhave been disclosed herein for purposes of illustration, it will be understood that various changes can be made in the form, details, arrangement and proportions of the various parts in such embodiments without departing from the spirit and scope of the invention as defined by the appended claims.
What I claimed is:
1. A marine derrick arrangement comprising a derrick boom, a pair of guy pendant deflecting sheaves aligned with the base of said derrick boom and located at an equal distance on both sides of said base, a common winch designed for winding two guy pendants, one said guy pendant being wound around said common winch at one end thereof and led through one of said guy pendant deflecting sheaves and then being connected to the top end of saidboom, the other said guy pendant being Wound around said common winch at one end thereof and led through the other of said pair of guy pendant deflecting sheaves and then being connected to the top end of said boom, elevated mounting means, and a topping lift wire extending from a winch means via said mounting means, the top end of said boom, back to said mounting means to a connection with one of said guy pendants.
2. A marine derrick arrangement as described in claim 1, wherein the end of said topping lift wire, which is connected to said at least one guy pendant, is disposed in such amanner as to exert a downward ,tensionon said guy pendant at the connected point.
3. A marine derrick arrangement according to claim 1, wherein said elevated mounting means comprises a derrick post.
4. A marine derrick arrangement as described in claim 3, wherein a frame is provided adjacent the base portion of said derrick post for securing two deflecting blocks for said at least one guy pendant.
5. A marine derrick arrangement according to claim 3, mounted upon a deck, wherein said topping lift wire is directed downward from the connection with said at least one guy pendant, andaround a sheave secured on said deck, then directed upward and around a block on the top ofsaid derrick post to a block secured to the free end of said boom, then around a second block on the top of said derrick post to said winch means.
References Cited by the Examiner 4 UNITED STATES PATENTS 2,5 5 9,832
ANDRES I-I. NIELSEN, Primary Examiner.

Claims (1)

1. A MARINE DERRICK ARRANGEMENT COMPRISING A DERRICK BOOM, A PAIR OF GUY PENDANT DEFLECTING SHEAVES ALIGNED WITH THE BASE OF SAID DERRICK BOOM AND LOCATED AT AN EQUAL DISTANCE ON BOTH SIDES OF SAID BASE, A COMMON WINCH DESIGNED FOR WINDING TWO GUY PENDANTS, ONE SAID GUY PENDANT BEING WOUND AROUND SAID COMMON WINCH AT ONE END THEREOF AND LED THROUGH ONE OF SAID GUY PENDANT DEFLECTING SHEAVES AND THEN BEING CONNECTED TO THE TOP END OF SAID BOOM, THE OTHER SAID GUY PENDANT BEING WOUND AROUND SAID COMMON WINCH AT ONE END THEREOF AND LED THROUGH THE OTHER OF SAID PAIR OF GUY PENDANT DEFLECTING SHEAVES AND THEN BEING CONNECTED TO THE TOP END OF SAID BOOM, ELEVATED MOUNTING MEANS, AND A TOPPING LIFT WIRE EXTENDING FROM A WINCH MEANS VIA SAID MOUNTING MEANS, THE TOP END OF SAID BOOM, BACK TO SAID MOUNTING MEANS TO A CONNECTION WITH ONE OF SAID GUY PENDANTS.
US521925A 1965-11-24 1966-01-20 Marine derrick arrangement Expired - Lifetime US3308965A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3430776A (en) * 1967-04-24 1969-03-04 Robert Morrison Derrick cranes and swinging derricks
US3610432A (en) * 1968-08-09 1971-10-05 Sadatomo Kuribayashi Marine derrick system
US3709375A (en) * 1969-01-10 1973-01-09 Speedcranes Ltd Cranes

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5574995A (en) * 1978-11-30 1980-06-05 Toshio Sou Doubleeswing automaticallyyaccelerated cargo work device

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2559832A (en) * 1945-09-11 1951-07-10 Slater Alexander Ship hoist
US2830710A (en) * 1955-07-01 1958-04-15 Jr William L Banks Cargo hoisting apparatus
US3144136A (en) * 1963-05-06 1964-08-11 United States Steel Corp Rope drive for swinging boom of a jib crane

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE22830C (en) *

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2559832A (en) * 1945-09-11 1951-07-10 Slater Alexander Ship hoist
US2830710A (en) * 1955-07-01 1958-04-15 Jr William L Banks Cargo hoisting apparatus
US3144136A (en) * 1963-05-06 1964-08-11 United States Steel Corp Rope drive for swinging boom of a jib crane

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3430776A (en) * 1967-04-24 1969-03-04 Robert Morrison Derrick cranes and swinging derricks
US3610432A (en) * 1968-08-09 1971-10-05 Sadatomo Kuribayashi Marine derrick system
US3709375A (en) * 1969-01-10 1973-01-09 Speedcranes Ltd Cranes

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GB1118756A (en) 1968-07-03
NO118695B (en) 1970-01-26

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