Self-standing light crane for LNG carrier liquid cargo tank

Abstract

The application relates to a self-standing light crane for a liquid cargo tank of an LNG ship, which comprises a base, a liftable tower body, a rotating mechanism, a telescopic boom, a steel wire rope, a lifting hook, two walking wheels and several supporting legs, the liftable tower body comprises several tower body sections which are sequentially sleeved from outside to inside, and the telescopic boom comprises several boom sections which are sleeved from outside to inside. The self-standing light crane for the liquid cargo tank of the LNG ship can reach a higher hoisting height under the premise of smaller overall quality, can adjust the horizontal or vertical state of the tower body and lift the tower body up and down through a self-driving structure, can adjust the luffing of the boom, does not need external additional fixing devices, can realize the folding of the overall structure, and can meet the size requirement of the entry and exit of the opening on the side of the ship cabin under the condition of minimized volume.

Description

Technical Field

[0001] This invention relates to the field of LNG ship cargo tank construction, and more specifically to a self-standing lightweight crane for LNG ship cargo tanks. Background Technology

[0002] After the LNG carrier's cargo containment system is completed, the scaffolding platform inside the hold needs to be dismantled. Because the hold is enclosed, high-lift cranes cannot be used for hoisting. Furthermore, the limited access to the hold and the load-bearing capacity of the scaffolding platform prevent the use of heavy and bulky truck cranes for access work. While manual dismantling combined with electric hoists can complete the dismantling of the scaffolding platform, it is too inefficient, and setting up the electric hoist attachment points inside the hold is difficult.

[0003] Existing cranes are heavy and bulky, while simple lifting equipment cannot reach the required lifting height. For example, prior art document CN216994762U discloses a lifting boom device for lifting items from LNG carrier cargo tanks, comprising a base, a column, a crossbeam, and a wire rope. The column is located inside the base, with one end extending out of the base and onto the crossbeam. Three fixed pulleys are mounted on the column and crossbeam, and a single wire rope is threaded through these pulleys. One end of the wire rope is sequentially equipped with a guide clamp, a counterweight limiter, a shackle, and a hook. Although this lifting boom device can meet the load-bearing requirements of the scaffolding platform inside the cargo tank and its size can accommodate the access dimensions of the ship's side openings, it is inconvenient to transport and has limited lifting height.

[0004] Therefore, designing and building a lightweight, compact crane with a lifting height that meets usage requirements is of great significance for the efficient and safe dismantling of scaffolding platforms inside cabins. Summary of the Invention

[0005] To address the technical problems existing in the prior art, this invention provides a self-standing lightweight crane for LNG carrier cargo tanks, which achieves a high lifting height while maintaining a small overall size and weight. The technical solution of this invention is as follows:

[0006] A self-standing lightweight crane for LNG carrier cargo tanks includes a base, a liftable tower, a rotating mechanism, a telescopic boom, a hook, two wheels, and several outriggers. The liftable tower comprises several tower sections nested sequentially from the outside to the inside, with the first tower section connected to the base. The telescopic boom comprises several boom sections nested sequentially from the outside to the inside, with the last tower section connected to the first boom section via the rotating mechanism. The hook is located below the last boom section. The two wheels are mounted on both sides of the base, and the outriggers are fixedly connected to the base via support pins.

[0007] As a preferred technical solution, a support mechanism is provided on each side of the first tower section. The support mechanism includes a tower support plate, short struts, and long struts. The tower support plate is welded to the first tower section. One end of the short strut and one end of the long strut are connected to the tower support plate via the same tower pin. One end of the base is rotatably connected to the other ends of the short strut and the long strut, respectively. The short struts and long struts are used to support the liftable tower section.

[0008] As a preferred technical solution, a base pulley system is installed on the base, and a hoisting motor, a wire rope drum, a fixed pulley, and a tower body pulley system are installed on the first tower section. The shaft of the hoisting motor is connected to the shaft of the wire rope drum, and a wire rope is wound on the drum. One end of the wire rope is fixed to the drum, and the wire rope sequentially passes through the tower body pulley system, the base pulley system, the fixed pulley, and the second tower section among several tower sections. The other end of the wire rope is connected to a hook. The hoisting motor rotates to raise and lower the wire rope, thereby adjusting the horizontal and vertical positions of the liftable tower. The hoisting motor drives the wire rope drum to rotate, and the raising and lowering of the wire rope is achieved by changing the direction of the hoisting motor. By tightening the length of the wire rope, the distance between the liftable tower body pulley system and the base pulley system can be reduced, allowing the tower to gradually change from a horizontal to a vertical position with the support of short and long struts. Similarly, by lengthening the steel wire rope, the tower can be lowered from a vertical position to a horizontal position.

[0009] As a preferred technical solution, the base is equipped with a horizontal pin and a horizontal pin socket, and the first tower section is equipped with a tower body tie plate. When the liftable tower body moves to a vertical position, the horizontal pin is inserted between the horizontal pin socket and the tower body tie plate, and the liftable tower body is fixed to the base. At this time, the steel wire rope continues to be retracted, and the steel wire rope pulls the second tower section upward. The remaining tower sections are connected by several ropes.

[0010] As a preferred technical solution, a tower lock is provided on the first tower section, and a tower locking plate is provided on the second tower section among several tower sections. The first tower section and the second tower section are fixed by inserting the tower lock into the lock hole of the tower locking plate.

[0011] As a preferred technical solution, the rotating mechanism includes a rotating motor, a large gear, a small gear, and a rotating base. The rotating motor is fixed to the top of the last tower section, and the rotating motor is fixedly connected to the center of the small gear. The large gear meshes with the small gear. The bottom end of the rotating base is rotatably connected to the top of the last tower section. The large gear is coaxially fixed to the outer side of the bottom end of the rotating base. The rotating base is connected to the first boom section. The rotating motor drives the small gear to rotate, which in turn drives the large gear and the rotating base to rotate, thereby driving the first boom section to rotate.

[0012] As a preferred technical solution, the first section of the boom is provided with a first fixing hole, and the rotating base is provided with a first mounting hole. The first section of the boom is rotatably connected to the rotating base by a first pin passing through the first fixing hole and the first mounting hole.

[0013] As a preferred technical solution, the first section of the boom is provided with a second fixing hole, and the rotating base is provided with a second mounting hole. The first section of the boom is horizontally fixed by a second pin passing through the second fixing hole and the second mounting hole.

[0014] As a preferred technical solution, the first section of the boom is provided with a third fixing hole, and the rotating base is provided with a third mounting hole. The first section of the boom is fixed upward by a third pin passing through the third fixing hole and the third mounting hole.

[0015] As a preferred technical solution, the upward tilt angle of the first section of the boom when it is fixed is 30°.

[0016] As a preferred technical solution, the first section of the boom is equipped with a telescopic motor and a lifting ring. The telescopic motor drives the telescopic boom to extend and retract. When the telescopic boom is retracted to its innermost position, the lifting wire rope is connected to the lifting ring.

[0017] As a preferred technical solution, the hook is equipped with a movable pulley, and one end of the wire rope is fixed to the last section of the boom. The hook is positioned below the telescopic boom via the wire rope passing over the movable pulley. When the first section of the tower is fixed to the base and the tower lock is engaged, the hook can be raised or lowered by extending or retracting the wire rope. The movable pulley installation of the hook increases the rated lifting capacity.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] (1) The overall design weight of the present invention is 1250kg, which can meet the load-bearing requirements of the scaffolding platform in the liquid cargo tank. It can be placed on the scaffolding platform for dismantling of the upper scaffolding.

[0020] (2) The maximum lifting height of the invention is 16 meters. The tower body can be adjusted horizontally or vertically and lifted up and down through its own transmission structure. The boom amplitude can be adjusted. No external additional fixing device is required to achieve a lifting weight of 200kg to 400kg.

[0021] (3) The design of the present invention can realize the overall structure to be folded down, and the volume can meet the access size requirements of the side opening of the cabin while minimizing the volume. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0023] Figure 2This is a schematic diagram of the retractable tower body of the present invention retracted to its lowest position.

[0024] Figure 3 This is a schematic diagram showing the connection between the base and the liftable tower body of the present invention.

[0025] Figure 4 This is a schematic diagram of the liftable tower body of the present invention raised to its highest point.

[0026] Figure 5 This is a schematic diagram of the liftable tower body locking mechanism of the present invention.

[0027] Figure 6 This is a schematic diagram of the first section of the boom of the present invention.

[0028] Figure 7 This is a schematic diagram of the rotating mechanism of the present invention.

[0029] Figure 8 This is a schematic diagram of the connection between the telescopic boom and the rotating mechanism of the present invention.

[0030] Figure 9 This is a schematic diagram of the telescopic boom tilting upwards according to the present invention.

[0031] Figure 10 This is a schematic diagram of the 2x lifting mode of the present invention.

[0032] In the diagram: 1. Base; 11. Traveling wheel; 12. Support leg; 13. Short support rod; 14. Long support rod; 15. Horizontal pin socket; 16. Horizontal pin; 17. Base pulley block; 2. First tower section; 21. Wire rope drum; 22. Hoisting motor; 23. Wire rope; 24. Fixed pulley; 25. Tower lock; 26. Tower tie plate; 27. Tower support plate; 28. Support rod pin; 29. ​​Tower pulley block; 3. Second tower section; 31. Tower locking plate; 4. Third tower section 5. Fourth tower section; 51. Rotary motor; 52. Small gear; 6. Rotating base; 61. Large gear; 62. First pin; 63. First mounting hole; 64. Second mounting hole; 65. Third mounting hole; 66. Second pin; 7. First boom section; 71. Telescopic motor; 72. Lifting ring; 73. First fixing hole; 74. Second fixing hole; 75. Third fixing hole; 76. Moving pulley; 8. Second boom section; 9. Third boom section; 10. Hook. Detailed Implementation

[0033] The technical solution of the present invention will be further described below with reference to specific embodiments:

[0034] like Figure 2 and Figure 4As shown, this embodiment provides a self-supporting lightweight crane for LNG carrier cargo tanks, including a base 1, a liftable tower body, a rotating mechanism, a telescopic boom, a hook 10, two wheels 11, and four legs 12. The liftable tower body includes a first tower section 2, a second tower section 3, a third tower section 4, and a fourth tower section 5, sequentially arranged from the outside to the inside. The first tower section 2 is connected to the base 1. The telescopic boom includes a first boom section 7, a second boom section 8, and a third boom section 9, sequentially arranged from the outside to the inside. The fourth tower section 5 is connected to the first boom section 7 via the rotating mechanism. The hook 10 is located below the third boom section 9. The two wheels 11 are respectively installed on both sides of the base 1. The legs 12 are each fixedly connected to the base 1 via a support pin. The base 1 has a rectangular frame structure, and a leg 12 is installed at each of the four corners of the base 1. The legs 12 can be retracted or extended, and after retraction or extension, they are fixed back to the base 1 via support pins.

[0035] The self-standing lightweight crane for the LNG carrier cargo tank in this embodiment can retract its outriggers 12, retract the first tower section 2, the second tower section 3, the third tower section 4, and the fourth tower section 5, and retract the first boom section 7, the second boom section 8, and the third boom section 9 to achieve a retracted state. It can be moved by human push through the wheels.

[0036] like Figure 3 and Figure 4 As shown, a support mechanism is provided on each side of the first tower section 2. The support mechanism includes a tower support plate 27, short support rods 13, and long support rods 14. The tower support plate 27 is welded to the first tower section 2. One end of the short support rod 13 and one end of the long support rod 14 are connected to the tower support plate 27 via the same tower support pin. One end of the base 1 is rotatably connected to the other ends of the short support rod 13 and the long support rod 14 via support rod pins 28. The short support rods 13 and the long support rods 14 are used to support the liftable tower body. The tower support plate 27 is made of Q235 steel.

[0037] like Figure 3 and Figure 4As shown, a base pulley block 17 is installed on the base 1, and a hoisting motor 22, a wire rope drum 21, a fixed pulley 24, and a tower body pulley block 29 are installed on the first tower body section 2. The shaft of the hoisting motor 22 is connected to the shaft of the wire rope drum 21. A wire rope 23 is wound on the wire rope drum 21. One end of the wire rope 23 is fixed to the wire rope drum 21. The wire rope 23 passes sequentially through the tower body pulley block 29, the base pulley block 17, the fixed pulley 24, and the second tower body section 3 among several tower body sections. The other end of the wire rope 23 is connected to the hook 10. The hoisting motor 22 rotates to raise and lower the wire rope 23, thereby achieving the adjustment of the horizontal and vertical state of the liftable tower body. The hoisting motor 22 drives the wire rope drum 21 to rotate. By changing the direction of the hoisting motor 22, the raising and lowering of the wire rope 23 is achieved. By tightening the steel wire rope 23, the distance between the liftable tower pulley block 29 and the base pulley block 17 can be reduced, allowing the tower to gradually change from a horizontal to a vertical state under the support of the short support rod 13 and the long support rod 14. Similarly, by lengthening the steel wire rope 23, the tower can be lowered from a vertical state to a horizontal state.

[0038] like Figure 3 As shown, a horizontal pin 16 and a horizontal pin socket 15 are provided on the base 1, and a tower body pull plate 26 is provided on the first tower body 2. When the liftable tower body is in a vertical position, the first tower body 2 is fixed to the base 1 by inserting the horizontal pin 16 between the horizontal pin socket 15 and the tower body pull plate 26. The wire rope 23 passes through the fixed pulley 24 and then through the bottom end of the second tower body 3. At this time, since the first tower body 2 is fixed to the base 1, the wire rope 23 is continuously pulled back, and the force on the wire rope 23 is transferred to the second tower body 3, thereby pulling the second tower body 3 upward. The remaining tower sections are connected by several ropes. Specifically, the bottom of the third tower section 4 and the top of the first tower section 2 are fixedly connected to the two ends of a rope. The length of this rope is close to the length of the second tower section 3, and the rope passes around the top of the second tower section 3. When the second tower section 3 rises, the third tower section 4 rises synchronously under the tension of the rope. The second tower section 3 and the fourth tower section 5 are also connected by another rope in the same way as the rope connection between the first tower section 2 and the third tower section 4, thus realizing the function of synchronous rise of each tower section.

[0039] like Figure 5 As shown, the first tower section 2 is equipped with a tower lock 25, and the second tower section 3, which consists of several tower sections, is equipped with a tower locking plate 31. By inserting the tower lock 25 into the lock hole of the tower locking plate 31, the first tower section 2 and the second tower section 3 are fixed together.

[0040] like Figure 8As shown, the rotating mechanism includes a rotary motor 51, a large gear 61, a small gear 52, and a rotating base 6. The rotary motor 51 is fixed to the top of the last tower section. The rotary motor 51 is fixedly connected to the center of the small gear 52. The large gear 61 meshes with the small gear 52. The bottom end of the rotating base 6 is rotatably connected to the top of the last tower section. The large gear 61 is coaxially fixed to the outer side of the bottom end of the rotating base 6. The rotating base 6 is connected to the first boom section 7. The rotary motor 51 drives the small gear 52 to rotate, which in turn drives the large gear 61 and the rotating base 6 to rotate, thereby driving the first boom section 7 to rotate.

[0041] like Figure 6 , Figure 7 and Figure 9 As shown, the first section of the boom 7 has a first fixing hole 73, and the rotating base 6 has a first mounting hole 63. The first section of the boom 7 is rotatably connected to the rotating base 6 by a first pin 62 passing through the first fixing hole 73 and the first mounting hole 63. This enables the boom to be retracted or extended.

[0042] like Figure 6 , Figure 7 and Figure 9 As shown, the first section of the boom 7 is provided with a second fixing hole 74, and the rotating base 6 is provided with a second mounting hole 64. The first section of the boom 7 is horizontally fixed by a second pin 66 passing through the second fixing hole 74 and the second mounting hole 64.

[0043] like Figure 6 , Figure 7 and Figure 9 As shown, the first section of the boom 7 is provided with a third fixing hole 75, and the rotating base 6 is provided with a third mounting hole 65. The first section of the boom 7 is fixed upward by a third pin passing through the third fixing hole 75 and the third mounting hole 65.

[0044] like Figure 9 As shown, the upward tilt angle of the first section of the boom 7 when it is fixed is 30°.

[0045] like Figure 1 and Figure 9 As shown, when the crane is in the retracted state and the liftable tower body is placed horizontally, the first section of the boom 7 is fixedly connected to the rotating base 6. If it is necessary for the boom to be in a horizontal state after the crane is extended, the second pin 66 is inserted into the second fixing hole 74 and the second mounting hole 64. If it is necessary for the boom to tilt upwards by 30° after the crane is extended, the third pin is inserted into the third fixing hole 75 and the third mounting hole 65. If it is necessary to retract the entire crane, the second pin 66 or the third pin is pulled out, and the first section of the boom 7 is rotated around the first pin 62, so that the telescopic boom moves closer to the liftable tower body.

[0046] like Figure 4 and Figure 6 As shown, the first section of the boom 7 is equipped with a telescopic motor 71 and a lifting ring 72. The telescopic motor 71 drives the telescopic boom to extend and retract. When the telescopic boom is retracted to the innermost side, the wire rope 23 can be connected to the lifting ring 72.

[0047] like Figure 10 As shown, the hook 10 is equipped with a movable pulley 76, and one end of the wire rope 23 is fixed to the last section of the boom. The hook 10 is positioned below the telescopic boom via the wire rope 23, which passes over the movable pulley 76. When the first tower section 2 is vertically fixed to the base 1 and the tower lock 25 is locked, the hook 10 can be raised or lowered by extending or retracting the wire rope 23. The installation of the hook 10 via the movable pulley 76 increases the rated lifting capacity. The adjustment of the first tower section 2 to horizontal or vertical positions, the raising of the second tower section 3, and the raising or lowering of the hook 10 are all achieved using the same wire rope 23.

[0048] This embodiment is merely a further explanation of the present invention and is not intended to limit the present invention. Those skilled in the art can make non-inventive modifications to this embodiment as needed after reading this specification, but such modifications are protected by patent law as long as they are within the scope of the claims of the present invention.

Claims

1. A self-standing lightweight crane for LNG carrier cargo tanks, characterized in that, The device includes a base, a liftable tower body, a rotating mechanism, a telescopic boom, a hook, two wheels, and several support legs. The liftable tower body comprises several tower sections sequentially arranged from the outside to the inside. The first tower section is connected to the base. The telescopic boom comprises several boom sections arranged from the outside to the inside. The last tower section is connected to the first boom section via the rotating mechanism. The hook is located below the last boom section. The two wheels are respectively installed on both sides of the base. The support legs are each fixedly connected to the base via a support pin. A support mechanism is provided on each side of the first tower section. The support mechanism includes a tower body support plate, a short support rod, and a long support rod. The tower body support plate is welded to the first tower section. One end of the short support rod and one end of the long support rod are connected to the tower body support plate through the same tower body pin. One side of the base is rotatably connected to the other end of the short support rod and the other end of the long support rod, respectively. The base is equipped with a base pulley assembly, and the first tower section is equipped with a hoisting motor, a wire rope drum, a fixed pulley, and a tower body pulley assembly. The shaft of the hoisting motor is connected to the shaft of the wire rope drum. A wire rope is wound on the wire rope drum. One end of the wire rope is fixed to the wire rope drum. The wire rope passes sequentially around the tower body pulley assembly, the base pulley assembly, the fixed pulley, and the second tower section among the several tower sections. The other end of the wire rope is connected to a hook. The base is provided with a horizontal pin and a horizontal pin socket, and the first section of the tower body is provided with a tower body pull plate. When the liftable tower body is in a vertical state, the horizontal pin is inserted between the horizontal pin socket and the tower body pull plate, and the liftable tower body is fixed on the base. The first tower section is equipped with a tower lock, and the second tower section among the plurality of tower sections is equipped with a tower locking plate. When the tower lock is inserted into the lock hole of the tower locking plate, the first tower section and the second tower section are fixedly connected. The rotating mechanism includes a rotating motor, a large gear, a small gear, and a rotating base. The rotating motor is fixed to the top of the last tower section. The rotating motor is fixedly connected to the center of the small gear. The large gear meshes with the small gear. The bottom end of the rotating base is rotatably connected to the top of the last tower section. The large gear is coaxially fixed to the outside of the bottom end of the rotating base. The rotating base is fixedly connected to the first section of the boom. The first section of the boom is provided with a first fixing hole, and the rotating base is provided with a first mounting hole. The first section of the boom is rotatably connected to the rotating base by a first pin passing through the first fixing hole and the first mounting hole. The first section of the boom is provided with a second fixing hole and a second pin, and the rotating base is provided with a second mounting hole. When the first section of the boom is horizontally fixed, the second pin passes through the second fixing hole and the second mounting hole. The first section of the boom is provided with a third fixing hole and a third pin, and the rotating base is provided with a third mounting hole. When the first section of the boom is fixed in an upward position, the third pin passes through the third fixing hole and the third mounting hole. The upward tilt angle of the first section of the boom when it is fixed is 30°. The first section of the boom is equipped with a telescopic motor and a lifting ring. The telescopic motor drives the telescopic boom to extend and retract. When the telescopic boom is retracted to its innermost position, the wire rope is connected to the lifting ring.

2. The self-standing lightweight crane for LNG carrier cargo tanks according to claim 1, characterized in that, The hook is equipped with a movable pulley, one end of the wire rope is fixed to the last section of the boom, and the hook is positioned below the telescopic boom by passing the wire rope around the movable pulley.

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