Overall arrangement method of AHC crane

Abstract

An overall arrangement method of an AHC crane is used for optimizing the layout of components or mechanisms of the AHC crane, the AHC crane comprises a base, a rotary platform is arranged on the base, a crane body is arranged on the rotary platform, a suspension arm is connected to one side of the crane body, and the crane body comprises a cab, a machine room and a main winch. A variable-amplitude oil cylinder is arranged between the crane main body and the suspension arm, and the main winch is configured to be a secondary control hydraulic system; the arrangement mode of the counterweight is optimized in combination with the layout, the overall overturning moment of the crane in the working state is effectively reduced, the structural stability and the anti-overturning capacity are enhanced, and the variable-amplitude oil cylinder is arranged above the cab, so that the oil cylinder is prevented from shielding the front and side view of operators in the cab; and a secondary control system is configured, so that the installed power requirement of the system is reduced, and the overall weight of the crane is further reduced while energy is saved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of cranes, in particular to a general arrangement method of an AHC crane. BACKGROUND

[0002] With the rapid development of marine engineering and shipping industry, the requirements for offshore hoisting equipment are increasing. Especially in offshore hoisting operations, the ship will produce periodic heaving motion due to wave action, which will cause displacement and impact of the hoisted load, seriously affecting the safety and stability of the operation. To solve this problem, a crane with active wave compensation function emerges as the times require. It can offset the impact of ship motion on the load by real-time control of the winch rope action, and realize stable hoisting. For the crane working on the ship, the weight of the crane is strictly required, and the overall weight of the crane should be reduced as much as possible when designing the structure. At the same time, the performance also needs to meet the requirements of work, and the change of structure should also adjust the overall structure layout of the crane to adapt to the operation on the ship. SUMMARY

[0003] The present application aims to solve the technical problem of poor overall layout of the AHC crane on the ship in the prior art.

[0004] To achieve the above purpose, the technical scheme of the present application is: a general arrangement method of an AHC crane, which is used to optimize the layout of components or mechanisms of the AHC crane. The AHC crane includes a base, a rotating platform is arranged on the base, a crane main body is arranged on the rotating platform, a hoist arm is connected to one side of the crane main body, the crane main body includes a cab, a machine room and a main winch, and a luffing cylinder is arranged between the crane main body and the hoist arm. The specific steps of the general arrangement method of the crane include: S1, the machine room is arranged behind the cab, and a fixed platform is formed between the machine room and the upper part of the cab, and the main winch is arranged on the fixed platform; S2, one end of the luffing cylinder is connected to the lower part of the hoist arm, and the other end of the luffing cylinder is connected to the upper part of the cab; S3, the main winch is configured as a secondary control hydraulic system.

[0005] The scheme, which centrally arranges the main winch and its driven machine room assembly at the rear side of the crane main body, optimizes the setting mode of the counterweight in combination with the layout, effectively reduces the overturning moment of the crane in the working state, enhances the structural stability and anti-overturning capacity; arranging the luffing cylinder driving the jib above the cab avoids the occlusion of the cylinder to the front and side views of the cab operator, thereby obtaining a more open and unobstructed operating view and improving the operation safety; meanwhile, the secondary control system is adopted to reduce the installed power demand of the system, thereby saving energy and further reducing the overall weight of the crane.

[0006] Further, the secondary control hydraulic system comprises an oil tank and a motor and a constant pressure variable pump connected together, the oil outlet P of the constant pressure variable pump is connected with a secondary element, the secondary element is connected with a controller, and the secondary element is connected with the main winch, a one-way valve is connected between the constant pressure variable pump and the secondary element, and the oil outlet of the constant pressure variable pump is also connected with an accumulator; the steady-state power is much smaller than that of the traditional system, and the same dynamic performance is achieved, thereby indirectly reducing the power generation demand of the whole ship, reducing the cooling water consumption, and optimizing the space layout.

[0007] Further, the secondary element has a hydraulic motor, the A oil port and the B oil port of the hydraulic motor are connected with the oil outlet P of the constant pressure variable pump and the oil return port T of the oil tank respectively; the hydraulic motor is connected with a displacement sensor, the other end of the displacement sensor is connected with the signal input end of the controller; the secondary element also has a high-frequency response valve, the control end of the high-frequency response valve is connected with the signal output end of the controller, the oil ports of the high-frequency response valve are in communication with the A oil port and the B oil port of the displacement sensor and the hydraulic motor, and a loop is formed which can be controlled; this makes the reaction of the secondary element more rapid and accurate, and the anti-interference ability is stronger, and the wave compensation can be better.

[0008] Further, the bottom diameter of the winch drum is D0, the diameter of the steel wire rope is d, and the number of layers of the steel wire rope wound on the drum is n, and then the calculated diameter R of the drum is obtained through the following formula: ; The load weight of the winch is m, and the mechanical efficiency of the lifting mechanism is η m , and the mechanical torque T generated by the load on the winch through the steel wire rope is M , which is obtained through the following formula: ; Further, the working pressure difference of the secondary control system is P, the displacement of the secondary element is V g , and the efficiency of the secondary element is η mh , and the hydraulic torque T generated by the secondary element on the winch is H , which is obtained through the following formula: ; The mechanical torque T M and the hydraulic torque T H are compared by the control system, so that the main winch retracts or releases the rope.

[0009] Further, the AHC crane further comprises a hook box and a resting rack, the resting rack is arranged on the deck of the ship, and the hook box is integrally arranged with the resting rack, so that the space occupation of the deck is reduced.

[0010] Further, the AHC crane further comprises a secondary winch, which is arranged on the upper side of the boom, so that the main winch and the secondary winch are separated, so that the crane can perform high-power underwater operation and also consider small-power on-ship operation; the use scene is more rich. BRIEF DESCRIPTION OF DRAWINGS

[0011] Figure 1 It is a schematic diagram of the overall structure of the embodiment of the present application; Figure 2 It is a hydraulic principle diagram of the secondary control system of the embodiment of the present application; Figure 3 It is a flowchart of the embodiment of the present application. DETAILED DESCRIPTION

[0012] The present application will be further described in detail below in combination with the drawings and specific embodiments.

[0013] As Figure 1 shown, a general arrangement method of an AHC crane is used to optimize the layout of components or mechanisms of the AHC crane, the AHC crane comprises a base 1, a rotating platform 2 is arranged on the base 1, a crane main body 3 is arranged on the rotating platform 2, a boom 4 is connected to one side of the crane main body 3, the crane main body 3 comprises a cab 31, a machine room 32 and a main winch 33, the machine room 32 is arranged at the rear of the cab 31, a fixed platform 30 is formed between the machine room 32 and the upper part of the cab 31, the main winch 33 is arranged on the fixed platform 30, the main winch 33, the machine room 32 and the cab 31 are all arranged at the crane main body 3, i.e. at the rear side of the crane, so that the overturning moment of the whole crane in the working state is reduced, and the structural stability and the anti-overturning capability are enhanced; at the same time, the arrangement of the machine room 32 is also convenient for the maintenance of the hydraulic system.

[0014] A luffing oil cylinder 5 is arranged between the crane main body 3 and the boom 4, one end of the luffing oil cylinder 5 is connected to the lower part of the boom 4, and the other end of the luffing oil cylinder 5 is connected to the upper part of the cab 31; the luffing oil cylinder avoids shielding the front and side views of the operator of the cab, so that a more open and unobstructed operation view is obtained, and the operation safety is improved.

[0015] AsFigure 2 As shown, in the embodiment, the main winch 33 is configured as a secondary control hydraulic system, which comprises an oil tank and a motor 100 and a constant pressure variable pump 200 connected together, the oil outlet P of the constant pressure variable pump 200 is connected with a secondary element 300, the secondary element 300 is connected with a controller 400, and the secondary element 300 is connected with the main winch 33, a one-way valve 500 is connected between the constant pressure variable pump 200 and the secondary element 300, and the oil outlet of the constant pressure variable pump 200 is also connected with an accumulator 600; the gravity of the load drives the main winch 33 to reverse, and in turn drives the secondary element 300 to rotate, in the case that the load is lowered passively under the passive reverse of the main winch 33, the secondary element 300 functions as an oil pump, the potential energy of the load is converted into mechanical energy of the main winch 33 to drive the oil pump to suck oil from the low pressure port and output from the high pressure port, realizing the conversion of mechanical energy to hydraulic energy, and the output high pressure oil is stored in the accumulator 600 for use next time when the load is lifted.

[0016] The secondary element 300 has a hydraulic motor 301, the A oil port and the B oil port of the hydraulic motor 301 are connected with the oil outlet P of the constant pressure variable pump 200 and the oil return port T of the oil tank respectively; the hydraulic motor 301 is connected with a displacement sensor 302, the other end of the displacement sensor 302 is connected with the signal input end of the controller 400; the secondary element 300 also has a high frequency valve 303, the control end of the high frequency valve 303 is connected with the signal output end of the controller 400, the oil ports of the high frequency valve 303 are in communication with the A oil port and the B oil port of the hydraulic motor 301 and the displacement sensor 302, and can form a controllable loop; the controller 400 outputs a control signal to the high frequency valve 303 to control the opening and closing of the high frequency valve 303 and the size of the opening, and the size of the opening of the high frequency valve 303 determines the displacement of the secondary element 300.

[0017] In the embodiment, the calculated diameter of the drum can be obtained by the following formula: ; Wherein D0 is the bottom diameter of the drum of the winch, d is the diameter of the steel wire rope, and n is the number of layers of the steel wire rope wound on the drum; and the mechanical torque T M exerted by the load on the winch through the steel wire rope is obtained by the following formula: ; Wherein m is the weight of the load of the winch, η m is the mechanical efficiency of the lifting mechanism; and the hydraulic torque T H exerted by the secondary element 300 on the winch is obtained by the following formula: ; Wherein P is the working pressure difference of the secondary control system, V gFor the displacement of secondary components, η mh For the efficiency of the secondary components, since the secondary control system operates under a constant pressure difference, If P is a constant, then the hydraulic torque borne by the winch is only related to the actual displacement of the secondary components.

[0018] When the load size and the number of layers of wire rope remain constant, the mechanical torque T M Alternatively, it can be considered a constant, in which case the rate of increase depends only on the displacement of the secondary element 300; under closed-loop control, the secondary element 300 can always find a critical displacement V. g0 This makes the hydraulic torque and mechanical torque equal, thereby changing the actual displacement V. g To adjust the speed.

[0019] When the displacement of secondary element 300 is the critical displacement V g0 At that time, the mechanical torque equals the hydraulic torque, i.e., T H =T M When the main winch 33 is in a balanced state, neither pulling in nor releasing the rope, the load can be suspended in mid-air without falling even when the brake is engaged; when the ship is on calm sea surface, the control system keeps the secondary components at critical displacement.

[0020] When the displacement of secondary element 300 is greater than the critical displacement Vg0, the mechanical torque is less than the hydraulic torque, i.e., T H >T M The main winch 33 actively rotates forward to lift the load. At this time, the secondary element 300 acts as a hydraulic motor to realize the conversion of hydraulic energy into mechanical energy. When the ship descends with the waves, the control system increases the displacement of the secondary element 300, driving the main winch to rotate forward to wind up the rope.

[0021] When the displacement of secondary element 300 is less than the critical displacement Vg0, the mechanical torque is greater than the hydraulic torque, i.e., T H <T M When the main winch 33 is passively reversed to lower the load, the secondary element 300 acts as an oil pump. The gravitational potential energy of the load is converted into the mechanical energy of the main winch 33, which drives the oil pump to draw oil from the low-pressure port and output it from the high-pressure port, thus realizing the conversion of mechanical energy into hydraulic energy. The output high-pressure oil is stored in the accumulator 600 and can be used for the next load lifting. When the ship rises with the waves, the control system reduces the displacement of the secondary element 300, and the main winch 33 reverses under the counter-pull of the load to release the wire rope, thus counteracting the upward movement of the ship.

[0022] The lifting compensation operations are all adjusted by the controller 400 to adjust the size of the high-frequency valve 303 opening, so as to change the displacement of the secondary element 300, so that the main winch 33 actively reels or passively releases the rope; and the speed is adjusted by changing the displacement of the secondary element 300 on the winch, which has the advantages of fast response speed, high precision and high repeatability, and can improve the precision of wave compensation; and because there is no problem of converting gravitational potential energy into heat energy, a large-power hydraulic oil cooling system is not needed, and the overall weight of the crane is reduced.

[0023] In the embodiment, the AHC crane further comprises a hook box 6 and a resting rack 7, the resting rack 7 is arranged on the deck of the ship, and the hook box 6 is integrally arranged with the resting rack 7, thereby reducing the space occupation of the deck of the ship.

[0024] In the embodiment, the AHC crane further comprises a secondary winch 8 arranged on the upper side of the boom 4; the secondary winch 8 separates the light and high-frequency operation from the heavy operation borne by the main winch 33, so that the crane can quickly switch to cope with more complex offshore tasks, and the use scenarios are more abundant.

[0025] The specific steps of the overall arrangement method of the crane include: S1, the machine room 32 is arranged behind the cab 31, and the machine room 32 and the upper side of the cab 31 form a fixed platform 30, and the main winch 33 is arranged on the fixed platform 30; S2, one end of the luffing oil cylinder 5 is connected to the lower side of the boom 4, and the other end of the luffing oil cylinder 5 is connected to the upper side of the cab 31; S3, the main winch 33 is configured as a secondary control hydraulic system.

[0026] The above structure arranges the main winch 33 and the machine room 32 on the rear side of the crane, reduces the overall overturning moment of the crane in the working state, enhances the structural stability and anti-overturning ability; arranging the luffing oil cylinder 5 above the cab avoids the shielding of the luffing oil cylinder 5 to the front and side views of the operator of the cab; and the main winch 33 adopts a secondary control system, which reduces the installed power demand of the system, saves energy, and further reduces the overall weight of the crane.

Claims

1. A method of general arrangement of an AHC crane for optimizing the layout of components or mechanisms of an AHC crane, the AHC crane comprising a base (1) on which a slewing platform (2) is arranged, characterized in that: A crane main body (3) is arranged on the slewing platform (2), one side of the crane main body (3) is connected with a lifting arm (4), the crane main body (3) comprises a cab (31), a machine room (32) and a main winch (33), a luffing oil cylinder (5) is arranged between the crane main body (3) and the lifting arm (4); the specific steps of the overall arrangement method of the crane comprise: S1, the machine room (32) is arranged behind the cab (31), the machine room (32) and the upper part of the cab (31) form a fixed platform (30), and the main winch (33) is arranged on the fixed platform (30); S2, one end of the luffing oil cylinder (5) is connected below the lifting arm (4), and the other end of the luffing oil cylinder (5) is connected above the cab (31); S3, the main winch (33) is configured as a secondary control hydraulic system.

2. A method of general arrangement of an AHC crane according to claim 1, characterized in that: The secondary control hydraulic system comprises an oil tank, a motor (100) and a constant pressure variable pump (200) connected together, the oil outlet P of the constant pressure variable pump (200) is connected with a secondary element (300), the secondary element (300) is connected with a controller (400), and the secondary element (300) is connected with the main winch (33) at the same time, a one-way valve (500) is connected between the constant pressure variable pump (200) and the secondary element (300), and the oil outlet of the constant pressure variable pump (200) is also connected with an accumulator (600).

3. A method of overall arrangement of an AHC crane according to claim 2, characterized in that: The secondary element (300) has a hydraulic motor (301), the A oil port and the B oil port of the hydraulic motor (301) are connected with the oil outlet P of the constant pressure variable pump (200) and the oil return port T of the oil tank respectively; The hydraulic motor (301) is connected with a displacement sensor (302), the other end of the displacement sensor (302) is connected with the signal input end of the controller (400); the secondary element (300) further has a high-frequency response valve (303), the control end of the high-frequency response valve (303) is connected with the signal output end of the controller (400), the oil ports of the high-frequency response valve (303) are in communication with the displacement sensor (302) and the A oil port and the B oil port of the hydraulic motor (301), and a loop is formed in a controllable manner.

4. The method of general arrangement of an AHC crane according to claim 3, characterized in that: The bottom diameter of the winch drum is D0, the diameter of the steel wire rope is d, the number of layers of the steel wire rope wound on the drum is n, and the calculated diameter R of the drum is obtained by the following formula: ； The load weight of the winch is m, and the mechanical efficiency of the lifting mechanism is η m The mechanical torque T generated by the load on the winch through the steel wire rope M is obtained by the following formula: 。 5. A method of overall arrangement of an AHC crane according to claim 4, characterized in that: The working pressure difference of the secondary control system is P, the displacement of the secondary element is V g , the efficiency of the secondary element is η mh The hydraulic torque T generated by the secondary element to the winch is H obtained by the following formula: ； The mechanical torque T M and the hydraulic torque T H are compared by the control system, so that the main winch (33) is either taken up or let out.

6. The method of overall arrangement of an AHC crane according to claim 1, characterized in that: The AHC crane further comprises a hook box (6) and a rest rack (7), the rest rack (7) is arranged on the deck of the ship, and the hook box (6) is integrally arranged with the rest rack (7).

7. The method of overall arrangement of an AHC crane according to claim 1, characterized in that: The AHC crane is further provided with a secondary winch (8), and the secondary winch (8) is arranged on the upper side of the lifting arm (4).

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