Load limiting system of marine crane manned winch

Abstract

The utility model discloses a load limiting system of a marine crane manned winch, which is characterized in that under a manned mode and a loading mode, switching of a manned and loading switching valve is controlled, and a switching oil way controls and limits oil way hydraulic pressure through a loading limiting valve and a manned limiting valve respectively, so that the load limiting effect is realized; a full-hydraulic load limiting mode is adopted, and for a crane manned winch installed on an oil tanker or a liquefied natural gas ship, due to the fact that no electric control exists, expensive anti-explosion components are not needed, the control logic is simple and reliable, and the fault rate is low.

Description

Technical Field

[0001] The utility model relates to a load limiting system for a manned winch of a marine crane. Background Art

[0002] According to the classification society's crane manning regulations, ordinary cargo winches on ship cranes cannot be used to carry people because of the different design safety factors of cargo and passenger loads. If personnel transfer is required by crane, a dedicated winch with manning function must be configured. The winch has two different working loads: cargo and passenger. In order to ensure the design safety factor, each load must be set with a safety limit protection function, that is, when each load exceeds 1.1 times the preset working load, automatic protection must be implemented to prevent overload.

[0003] At present, the commonly used load limiting method is to install an axle pin sensor on the pulley carried by the crane wire rope to detect the tension of the wire rope hook. When the hook tension is detected to exceed 1.1 times the set value, the sensor instrument outputs a switch signal through the electronic control system to energize the corresponding solenoid valve controlling the winch lifting oil circuit, unload the oil circuit, and stop the winch lifting, which plays a safety protection role.

[0004] For crane manned winches installed on tankers or LNG ships, all electrical components need to be explosion-proof. The axle pin sensors, electrical switches and solenoid valves used in the above conventional load limiting methods need to meet IEC explosion-proof requirements, which will inevitably lead to problems such as high prices for hydraulic electrical components that meet this requirement, complex control systems and long delivery times. Utility Model Content

[0005] The purpose of the utility model is to solve the deficiencies of the above prior art, and proposes a fuel tank, a pump group, a main control valve group, a motor valve group and a manned and cargo switching valve, wherein the motor valve group includes a hydraulic motor, a brake, a manned load limit valve, a cargo load limit valve, a first hydraulically controlled one-way valve, a second hydraulically controlled one-way valve, a first one-way balancing valve, and a second one-way balancing valve;

[0006] The brake is arranged between the hydraulic motor and the reducer drum of the winch;

[0007] The main control valve group is provided with oil port A and oil port B. Oil port A is divided into two, one of which is connected to the hydraulic motor and the other is connected to the first oil inlet of the second shuttle valve. The oil outlet of the second shuttle valve is connected to the brake.

[0008] The oil port B is divided into two, one of which is connected to the hydraulic motor via the second one-way balance valve, and the other is connected to the oil port A via the load limiting valve;

[0009] The passenger and cargo switching valve is provided with an oil port X, which is divided into two after passing through the first one-way balancing valve, one of which is connected to the second hydraulically controlled reversing valve, and the other is connected to the hydraulic motor through the first hydraulically controlled reversing valve and the passenger load limiting valve.

[0010] Furthermore, a three-way flow regulating valve is connected between the pump group and the oil tank. The three-way flow regulating valve adjusts the flow output from the pump group to the actuator so that the pressure of the oil output by the pump is always higher than that of the actuator by a fixed value, thereby playing a role in energy saving.

[0011] Furthermore, the three-way flow control valve is connected in parallel with a pilot relief valve, which is used to adjust the maximum pressure of the three-way flow control valve, thereby limiting the load system pressure.

[0012] Furthermore, in order to ensure the cleanliness of the hydraulic oil entering the pilot relief valve and avoid clogging of the pilot relief valve, a filter is connected in series before the oil inlet of the pilot relief valve.

[0013] Furthermore, the oil port B of the main control valve group is connected to the second oil inlet of the second shuttle valve.

[0014] Furthermore, a brake pressure reducing valve and a two-position three-way valve are sequentially provided between the oil port A and the brake.

[0015] Furthermore, the oil outlet of the pump group is connected to a pressure cut-off valve.

[0016] Beneficial effects: 1. It adopts full hydraulic load limiting method, without electrical control, the control logic is simple and reliable, and the failure rate is low.

[0017] 2. Both the passenger load limit valve and the cargo load limit valve can be integrated into the motor valve group, without the need for external pipeline connection, and the structure is compact.

[0018] 3. For crane manned winches installed on tankers or LNG ships, since there is no electrical control, expensive explosion-proof components are not required, which can reduce manufacturing costs and improve product competitiveness.

[0019] 4. When switching to manning, the hydraulic motor is also switched to the light-load and high-speed manning mode, which improves work efficiency and effectively eliminates the possibility of misoperation when loading, thereby improving safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is the hydraulic principle diagram of the utility model; DETAILED DESCRIPTION

[0021] In order to deepen the understanding of the present invention, the present invention will be further described in detail below in conjunction with embodiments and drawings. The embodiments are only used to explain the present invention and do not constitute a limitation on the protection scope of the present invention.

[0022] like Figure 1 As shown, a load limiting system for a manned winch of a marine crane includes an oil tank 1, a pump group 2, a main control valve group 3, a manned and cargo switching valve 4, a manned load limiting valve 5, a first hydraulically controlled reversing valve 6, a cargo load limiting valve 7, a second hydraulically controlled reversing valve 8, a hydraulic motor 9, a brake 10, a main valve core of a multi-way valve 11, a first shuttle valve 12, a second shuttle valve 13, a third shuttle valve 14, a first one-way balancing valve 15, a second one-way balancing valve 16, a brake pressure reducing valve 17, a two-position three-way valve 18, a safety valve 19, a pilot relief valve 20, a three-way flow regulating valve 21, a filter 22, a stroke reversing valve 23, a pressure compensator 24, an oil pump 25, a motor valve group 26, and a pressure gauge stop valve 27.

[0023] The working principle of this embodiment under specific working conditions:

[0024] No-action condition: When pump group 2 is running, pump group 2 draws oil from oil tank 1, enters control valve group, and enters main control valve group 3. When main control valve group 3 is not operated, there is no hydraulic oil output from the working oil port of main control valve group 3, and the hydraulic oil output by pump group 2 is directly returned to oil tank 1 through main control valve group 3.

[0025] No-load condition: When the handle of the main control valve group 3 is pushed forward or pulled backward, hydraulic oil flows out of the oil port A of the main control valve group 3, and the oil port A is divided into two and outputs to the hydraulic motor 9 and the second shuttle valve 13 respectively. The hydraulic oil output by the second shuttle valve 13 flows to the brake 10 through the brake pressure reducing valve 17 and the two-position three-way valve 18, so that the brake 10 is opened, and the hydraulic motor rotates forward or reversely, driving the reducer drum to realize the lifting and lowering of the wire rope hook.

[0026] Loading condition: When the manned and loaded switching valve 4 is switched to the "load" position, the main control valve group 3 is operated to make the oil port B of the main control valve group 3 output hydraulic oil. The hydraulic oil output from the oil port B is divided into two after passing through the second one-way balance valve 16. One of the ways is output to the hydraulic motor 9, thereby increasing the tension of the winch wire rope hook; the other way is connected to the oil port A through the load limiting valve 7. When the tension on the hook increases, the pressure of the oil port B gradually increases. When the tension exceeds 1.1 times the designed load, the pressure of the oil port B also increases in proportion to the overflow setting value of the load limiting valve 7. At this time, the load limiting valve begins to overflow, so that the pressure at the oil port B does not exceed the load setting value of the load limiting valve 7. The corresponding wire rope hook tension will not exceed 1.1 times the load design value, and the hook will no longer lift. Thereby playing a load limiting protection role.

[0027] Manned condition: When the manned and cargo switching valve 4 is switched to the "manned" position, the main control valve group 3 is operated to make the oil port B of the main control valve group 3 discharge hydraulic oil, and the oil port X of the manned and cargo switching valve discharges hydraulic oil at the same time. The oil port X is divided into two after passing through the first one-way balance valve 15. One way enters the second hydraulic control reversing valve 8 to activate the second hydraulic control reversing valve 8 and control the hydraulic motor 9 to make the hydraulic motor 9 enter the light load and high speed manned mode; the other way enters the first hydraulic control reversing valve 6 to activate the first hydraulic control reversing valve 6 to connect the oil port B to the oil port A through the cargo load limiting valve 7 and the manned load limiting valve 5. When the hook tension increases, the pressure of the oil port B gradually increases. When the tension exceeds 1.1 times the designed manned load, the pressure of the oil port B also increases in proportion to the manned setting value of the manned load limiting valve 5. At this time, the manned load limiting valve begins to overflow, so that the pressure of the oil port B does not exceed the manned setting value of the manned load limiting valve 5. The corresponding wire rope hook tension will not exceed 1.1 times the manned setting value, and the hook will no longer rise, thus playing a load limit protection role.

[0028] In this embodiment, the load limiting system of the manned winch of the marine crane includes an oil tank 1, a pump group 2, a main control valve group 3, a motor valve group 26 and a manned and cargo switching valve 4, wherein the motor valve group includes a hydraulic motor 9, a brake 10, a manned load limiting valve 5, a cargo load limiting valve 7, a first hydraulically controlled one-way valve 6, a second hydraulically controlled one-way valve 8, a first one-way balancing valve 15, and a second one-way balancing valve 16;

[0029] The brake 10 is arranged between the hydraulic motor 9 and the reducer drum of the winch;

[0030] The main control valve group 3 is provided with an oil port A and an oil port B. The oil port A is divided into two, one of which is connected to the hydraulic motor 9, and the other is connected to the first oil inlet of the second shuttle valve 13. The oil outlet of the second shuttle valve 13 is connected to the brake 10.

[0031] The oil port B is divided into two, one of which is connected to the hydraulic motor 9 via the second one-way balance valve 16, and the other is connected to the oil port A via the load limiting valve 7;

[0032] The passenger and cargo switching valve is provided with an oil port X, which is divided into two after passing through the first one-way balancing valve 15, one of which is connected to the second hydraulically controlled reversing valve 8, and the other is connected to the hydraulic motor 9 through the first hydraulically controlled reversing valve 6 and the passenger load limiting valve 5.

[0033] In this embodiment, a three-way flow regulating valve 21 is connected between the pump group 2 and the oil tank 1. The three-way flow regulating valve 21 adjusts the flow output from the pump group to the actuator so that the pressure of the oil output by the pump is always higher than that of the actuator by a fixed value, thereby achieving energy saving. The three-way flow regulating valve is connected in parallel with a pilot relief valve 20. The pilot relief valve 20 is used to adjust the maximum pressure of the three-way flow regulating valve 21, thereby limiting the load system pressure. A filter 22 is connected in series before the oil inlet of the pilot relief valve 20. The three-way flow regulating valve 21, the pilot relief valve 20 and the filter 22 together constitute a pressure regulating unit of the hydraulic system.

[0034] In this embodiment, the oil port B of the main control valve group 3 is connected to the second oil inlet of the second shuttle valve 13 .

[0035] In this embodiment, a brake pressure reducing valve 17 and a two-position three-way valve 18 are sequentially provided between the oil port A and the brake 10 .

[0036] In this embodiment, the oil outlet of the pump group is connected to a pressure cut-off valve 27 .

[0037] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A load limiting system for a manned winch of a marine crane, characterized in that: It includes an oil tank, a pump group, a main control valve group, a motor valve group and a manned and cargo switching valve. The motor valve group includes a hydraulic motor, a brake, a manned load limit valve, a cargo load limit valve, a first hydraulically controlled one-way valve, a second hydraulically controlled one-way valve, a first one-way balancing valve, and a second one-way balancing valve; The brake is arranged between the hydraulic motor and the reducer drum of the winch; The main control valve group is provided with oil port A and oil port B. Oil port A is divided into two, one of which is connected to the hydraulic motor and the other is connected to the first oil inlet of the second shuttle valve. The oil outlet of the second shuttle valve is connected to the brake. The oil port B is divided into two, one of which is connected to the hydraulic motor via the second one-way balance valve, and the other is connected to the oil port A via the load limiting valve; The passenger and cargo switching valve is provided with an oil port X, which is divided into two after passing through the first one-way balancing valve, one of which is connected to the second hydraulically controlled reversing valve, and the other is connected to the hydraulic motor through the first hydraulically controlled reversing valve and the passenger load limiting valve.

2. A load limiting system for a manned winch of a marine crane according to claim 1, characterized in that: A three-way flow regulating valve is connected between the pump group and the oil tank.

3. A load limiting system for a manned winch of a marine crane according to claim 2, characterized in that: The three-way flow regulating valve is connected in parallel with a pilot relief valve.

4. A load limiting system for a manned winch of a marine crane according to claim 3, characterized in that: A filter is connected in series before the oil inlet of the pilot relief valve.

5. A load limiting system for a manned winch of a marine crane according to claim 4, characterized in that: The oil port B of the main control valve group is connected to the second oil inlet of the second shuttle valve.

6. The load limiting system for a manned winch of a marine crane according to claim 1, characterized in that: A brake pressure reducing valve and a two-position three-way valve are arranged in sequence between the oil port A and the brake.

7. The load limiting system for a manned winch of a marine crane according to claim 1, characterized in that: The oil outlet of the pump group is connected with a pressure cut-off valve.

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