Method for testing strength of B-type cabin under extreme shallow draft working condition

Abstract

The invention discloses a method for testing the strength of a B-type cabin under an extreme shallow draft working condition, which comprises a method for testing the strength of the B-type cabin under the extreme shallow draft working condition, and is characterized in that the B-type cabin is provided with a first cabin, a second cabin, a third cabin and a fourth cabin which are sequentially connected through pipelines; each of the first cabin, the second cabin, the third cabin and the fourth cabin is divided into a left cabin and a right cabin, and the left cabin and the right cabin are arranged on a ship in an experimental water area side by side; s1, injecting water into the left cabin of the first cabin and the right cabin of the third cabin; s2, water is injected into the first cabin and the third cabin; s3, water in the first cabin and the third cabin is emptied, and water is injected into the second left cabin and the fourth right cabin; the device solves the problems that a current B-type cabin strength test can only be carried out in a deeper water area, and the test period is long.

Description

Technical Field

[0001] The invention relates to the technical field of ship design, and in particular to a strength test method for a type B tank under an extreme shallow draft condition. Background Art

[0002] In the field of ship design and manufacturing, the strength test of type B tanks is an important part of ensuring the safety of ship structures. Traditionally, such tests are usually conducted by injecting water into the tank to increase the pressure inside the tank and observing the deformation and structural integrity of the bulkhead under different pressures. However, this method faces some challenges in actual operation, especially under extreme shallow draft conditions. Firstly, the traditional method requires a large amount of water to fill the cabin in order to reach the required test pressure, which not only increases the cost of the test but may also be difficult to achieve in certain waters (such as shallow rivers) because a large amount of water is needed to raise the water level in the cabin, thereby increasing the total weight of the cabin, forcing the Type B cabin to be tested only in deeper waters with a long test cycle. Therefore, a strength test method for Type B cabin under extreme shallow draft conditions is provided to solve the problem that the test can only be carried out in deeper waters with a long test cycle. Summary of the invention

[0003] The purpose of the present invention is to propose a strength test method for type B tanks under extreme shallow draft conditions, which is used to solve the technical problems in the prior art that the strength test of type B tanks has a long water filling time, a long dock cycle, and the water depth in the waters cannot guarantee the strength test of a single type B tank.

[0004] In order to solve the above technical problems, the present invention provides the following technical solutions: a strength test method of a type B tank under extreme shallow draft conditions, including a strength test method of a type B tank under extreme shallow draft conditions, characterized in that: a No. 1 tank, a No. 2 tank, a No. 3 tank and a No. 4 tank connected in sequence by pipelines are arranged on the type B tank, and the No. 1 tank, the No. 2 tank, the No. 3 tank and the No. 4 tank are all divided into left and right cabins, and the left and right cabins are placed side by side on a ship in the experimental waters; The method comprises: Step S1: Filling the left cabin of cabin No. 1 and the right cabin of cabin No. 3 with water to check the strength and air tightness of the bulkheads in cabin No. 1 and cabin No. 3; Step S2: injecting water into the No. 1 cabin and the No. 3 cabin to check the strength and air tightness of the No. 1 cabin and the No. 3 cabin; Step S3: drain the water in the No. 1 cabin and the No. 3 cabin, inject water into the No. 2 left cabin and the No. 4 right cabin, and check the strength and air tightness of the walls of the No. 2 cabin and the No. 4 cabin; Step S4: Fill water into the No. 4 left cabin and the No. 4 right cabin, and fill water into the No. 1 cabin and the No. 2 cabin until the hull is balanced, and check the strength and air tightness of the No. 4 right cabin; Step S5: swap the left and right cabins in cabin No. 1, cabin No. 2, and cabin No. 3, and check the strength and air tightness of the left cabin No. 4; Step S6: Add water to the No. 2 right cabin and the No. 2 left cabin, drain the No. 4 right cabin, keep the No. 4 left cabin unchanged, empty the No. 1 cabin, and check the strength and air tightness of the No. 2 cabin.

[0005] The present invention further states that the pipeline includes a low-pressure pipeline, a high-pressure pipeline and a pump body, the number of the pump bodies is the same as that of the B-type cabins, and the pump bodies correspond to the B-type cabins one by one; In each B-type cabin, a corresponding pump body is connected to the left and right cabins of the corresponding B-type cabin through two high-pressure pipelines, and a corresponding pump body is also connected to the left and right cabins of the corresponding B-type cabin through two low-pressure pipelines, and the pump body controls the water volume of the left and right cabins in the same B-type cabin respectively; In two adjacent different B-type cabins, the cabins on the same side are connected by low-pressure pipelines.

[0006] The present invention further describes that the above-mentioned pipeline is used to inject water into and drain water from the B-type tank, including the following methods: When a strength test is required for a certain compartment of a type B tank, and when the adjacent compartments of the compartment to be tested are kept in an unloaded state, the pump corresponding to the type B tank where the compartment is located is started, and the pump is connected to inject water into the compartment through a pipeline, and the water injection amount of each compartment is controlled. When the water in the compartment is about to reach the required water level, the output power of the pump is reduced, and the pump is injected into the compartment through a low-pressure pipeline until the water in the compartment reaches the required water level, thereby completing the strength test of the corresponding compartment; When it is necessary to drain the cabin that has completed the test and conduct a strength test on its adjacent cabin, the valve of the pipeline between the two adjacent cabins is opened, and the water in the cabin to be drained is injected into the cabin to be tested under the action of pressure. When the water pressure in the two cabins is equal or the water in the cabin to be tested reaches the required water level, the valve of the pipeline between the two cabins is closed, and the corresponding pumps of the two cabins are started. The pumps are filled and pumped to make the water level in the corresponding cabins reach the test requirements, and the strength test of the corresponding cabins is completed.

[0007] The present invention further illustrates that before step S1, the following steps are also included: Step S 01 : Before the test, all compartments are kept empty, and the draft of the hull is measured and recorded; Step S 02:It is known that the maximum pressure carried by the B-type tank during operation is P1. It can be known that the rated height of the horizontal plane in the B-type tank from the bottom of the tank should be h. The weight of the water in the tank is calculated to be m1, and the rated draft is obtained as L. When L is less than or equal to the water depth of the water area, the required pressure in the tank during the test is P1; when L is greater than the water depth, the required pressure in the tank during the test is P1+△p, and △p is the pressure that needs to be increased in the tank during the test. △p is proportional to the difference between the water depth and L. At this time, the rated height of the horizontal plane in the B-type tank from the bottom of the tank should be h1, and the weight of the water in the B-type tank is m2; Step S 03 :Adjust the pressure in the cabin according to the test plan. When the pressure in the cabin is adjusted to P1+△p, start the test.

[0008] The present invention further states that the step of adjusting the pressure in the cabin according to the test plan includes: A pressure pump 9 is fixedly connected to the inside of each left and right cabin of the B-type cabin, and the pressure in the cabin is adjusted by compressing the air in the cabin by the pressure pump 9.

[0009] The present invention further describes that the water volume of the left and right cabins in the same B-type cabin is controlled separately, including: The No. 1 tank 1 includes a No. 1 tank body, and a No. 1 bulkhead is fixedly connected inside the No. 1 tank body to divide the interior of the No. 1 tank body into a No. 1 left tank chamber and a No. 1 right tank chamber, so that the water in the left and right tank chambers of the No. 1 tank body cannot flow to each other; The water in the tank to be drained is injected into the tank to be tested under pressure, including: The No. 1 compartment further comprises a No. 1 compartment sealing door, and the No. 1 compartment sealing door is provided on the No. 1 bulkhead, and the No. 1 compartment sealing door is controlled to be opened so that the water in the compartment to be drained can be injected into the compartment to be tested; The pump body injects water into the cabin through a pipeline, including: A left water inlet hole for cabin No. 1 and a right water inlet hole for cabin No. 1 are opened above the tank body of cabin No. 1, and water is injected into the left cabin No. 1 through a pipeline connection between the left water inlet hole for cabin No. 1 and the pump body 1, and water is injected into the right cabin No. 1 through a pipeline connection between the right water inlet hole for cabin No. 1 and the pump body 1.

[0010] The present invention further illustrates that the calculation of the weight of the water in the cabin includes: It is known that the internal volume of the B-type cabin is C and the internal height is α. By setting the left and right cabins in the B-type cabin to the same shape, the volume of each cabin is , get the .

[0011] The present invention further describes that the control of the water injection amount of each compartment includes: Liquid level detectors are arranged in the left and right compartments of the B-type tank, and the depth of water in the compartment is detected by the liquid level detectors. When the water depth required for the water test is reached, an alarm is sounded to request the staff to stop injecting water.

[0012] The present invention further illustrates that the control of the water injection amount of each compartment also includes: A thick and rapid water flow is injected into the corresponding compartment through the high-pressure pipeline. When the required water volume is about to be reached, a thin and slow water flow is injected into the corresponding compartment through the low-pressure pipeline until the required water volume is reached.

[0013] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: the present invention calculates the required test pressure by the draft of the hull and the maximum pressure of the B-type tank. When the required test pressure exceeds the maximum pressure allowed by the water area, the pressure in the cabin is adjusted by a pressure pump so that the test can be carried out in shallower waters. Through the pipeline system, the pump body corresponds to the B-type cabin one by one, and the water volume in each cabin can be controlled separately. This not only improves the flexibility of the test, but also can accurately control the water level in the cabin and save experimental time. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings: Figure 1 is a schematic diagram of the overall front structure of an embodiment of the present invention; Figure 2 This is a schematic structural diagram of cabin No. 1 according to an embodiment of the present invention; Figure 3 is a schematic diagram of the overall top view structure of an embodiment of the present invention; Figure 4 is a schematic diagram of the structure of a pipeline system according to an embodiment of the present invention; Figure 5 is a schematic diagram of a comparative test before and after changing the air pressure in the cabin according to an embodiment of the present invention; Figure 6 is a schematic structural diagram of step S1 of an embodiment of the present invention; Figure 7 is a schematic diagram of the structure of step S2 of an embodiment of the present invention, Figure 8 is a schematic diagram of the structure of step S3 of an embodiment of the present invention; Fig. 9 is a schematic structural diagram of step S4 of an embodiment of the present invention; Fig.10 is a schematic structural diagram of step S5 of an embodiment of the present invention; Fig.11 is a schematic structural diagram of step S6 of an embodiment of the present invention; In the figure: 1. No. 1 cabin; 101. No. 1 cabin left water inlet; 102. No. 1 cabin right water inlet; 103. No. 1 left cabin; 104. No. 1 right cabin; 105. No. 1 cabin sealed door; 106. No. 1 cabin tank; 107. No. 1 bulkhead; 2. No. 2 cabin; 201. No. 2 cabin left water inlet; 202. No. 2 cabin right water inlet; 203. No. 2 left cabin; 204. No. 2 right cabin; 205. No. 2 cabin sealed door; 3. No. 3 cabin Cabin; 301, left water inlet of cabin No. 3; 302, right water inlet of cabin No. 3; 303, left cabin No. 3; 304, right cabin No. 3; 305, sealed door of cabin No. 3; 4, cabin No. 4; 401, left water inlet of cabin No. 4; 402, right water inlet of cabin No. 4; 403, left cabin No. 4; 404, right cabin No. 4; 405, sealed door of cabin No. 4; 5, pump body one; 6, pump body two; 7, pump body three; 8, pump body four; 9, pressure pump. DETAILED DESCRIPTION

[0015] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0016] See also Figure 1 — Figure 4 The present invention provides a technical solution: a strength test method for a type B tank under extreme shallow draft conditions, including a No. 1 tank 1 and a piping system.

[0017] like Figure 1 As shown, in certain embodiments, the No. 1 compartment 1 is connected to the No. 2 compartment 2 through a pipeline, the No. 2 compartment 2 is connected to the No. 3 compartment 3 through a pipeline, the No. 3 compartment 3 is connected to the No. 4 compartment 4 through a pipeline, and the No. 1 compartment 1, No. 2 compartment 2, No. 3 compartment 3 and No. 4 compartment 4 are placed side by side on the ship in the experimental waters.

[0018] like Figure 2 As shown, in some embodiments, the No. 1 cabin 1 includes a No. 1 cabin tank body 106 and a No. 1 bulkhead 107. The interior of the No. 1 cabin tank body 106 is fixedly connected to the No. 1 bulkhead 107. The No. 1 bulkhead 107 evenly divides the interior of the No. 1 cabin tank body 106 into a No. 1 left cabin 103 and a No. 1 right cabin 104. The No. 1 left cabin 103 and the No. 1 right cabin 104 have the same shape.

[0019] The No. 1 cabin 1 also includes a No. 1 cabin sealing door 105, which is opened on the No. 1 bulkhead 107, and is used to control the communication and separation between the No. 1 left cabin 103 and the No. 1 right cabin 104. A No. 1 cabin left water inlet 101 and a No. 1 cabin right water inlet 102 are opened above the No. 1 cabin tank 106, and the No. 1 cabin left water inlet 101 is used to drain water to the No. 1 left cabin 103, and the No. 1 cabin right water inlet 102 is used to drain water to the No. 1 right cabin 104.

[0020] Two pressure pumps 9 are fixedly connected to the top of the inner wall of the No. 1 cabin tank 106. Each of the pressure pumps 9 is located inside the No. 1 left cabin 103 and the No. 1 right cabin 104 respectively. The pressure pump 9 is used to change the internal pressure of the cabin by compressing the air in the cabin.

[0021] like Figure 3 As shown, in some embodiments, the No. 2 cabin 2 includes a No. 2 cabin left water inlet 201, a No. 2 cabin right water inlet 202, a No. 2 left cabin 203, a No. 2 right cabin 204 and a No. 2 cabin sealing door 205; The No. 3 cabin 3 comprises a No. 3 cabin left water inlet 301, a No. 3 cabin right water inlet 302, a No. 3 left cabin 303, a No. 3 right cabin 304 and a No. 3 cabin sealing door 305; The No. 4 cabin 4 comprises a No. 4 cabin left water inlet 401, a No. 4 cabin right water inlet 402, a No. 4 left cabin 403, a No. 4 right cabin 404 and a No. 4 cabin sealing door 405; The structures of cabin No. 1 1 , cabin No. 2 2 , cabin No. 3 3 and cabin No. 4 4 are the same and will not be described in detail herein.

[0022] Embodiment 1: In this embodiment, a pipeline system is provided, such as Figure 4 As shown, in some embodiments, the pipeline system includes a low-pressure pipeline and a high-pressure pipeline. The low-pressure pipeline is the black line part in the figure, and the low-pressure pipeline is used for the passage of small and slow water flows. The high-pressure pipeline is the red line part in the figure, and the high-pressure pipeline is used for the passage of large and turbulent water flows.

[0023] The pipeline system includes pump body 1 5, pump body 2 6, pump body 3 7 and pump body 4 8, wherein: The pump body 15 includes a water inlet, a low-pressure water outlet and two high-pressure water outlets. The water inlet of the pump body is connected to the river water through a pipeline, and the two high-pressure water outlets of the pump body are respectively connected to the pipelines of the No. 1 left cabin 103 and the No. 1 right cabin 104. The low-pressure water outlet of the pump body is connected to the No. 1 left cabin 103 and the No. 1 right cabin 104 through a three-branch pipeline, the No. 1 left cabin 103 and the No. 2 left cabin 203 are connected by pipeline, a flow meter is connected on the pipeline between the No. 1 left cabin 103 and the No. 2 left cabin 203, the No. 1 right cabin 104 and the No. 2 right cabin 204 are connected by pipeline, and a flow meter is connected on the pipeline between the No. 1 right cabin 104 and the No. 2 right cabin 204.

[0024] The pump body 2 6 includes a pump body 2 water inlet, a pump body 2 low-pressure water outlet and two pump body 2 high-pressure water outlets. The pump body 2 water inlet is connected to the river water through a pipeline, and the two pump body 2 high-pressure water outlets are respectively connected to the No. 2 left cabin 203 and the No. 2 right cabin 204 through pipelines, the pump body 2 low-pressure water outlet is connected to the No. 2 left cabin 203 and the No. 2 right cabin 204 through a three-branch pipeline, the No. 2 left cabin 203 is connected to the No. 3 left cabin 303 through a pipeline, a flow meter is connected to the pipeline between the No. 2 left cabin 203 and the No. 3 left cabin 303, the No. 2 right cabin 204 is connected to the No. 3 right cabin 304 through a pipeline, and a flow meter is connected to the pipeline between the No. 2 right cabin 204 and the No. 3 right cabin 304.

[0025] The pump body three 7 includes three water inlets, three low-pressure water outlets and two three high-pressure water outlets. The three water inlets are connected to the river water through pipelines. The two three high-pressure water outlets are respectively connected to the pipelines of the third left cabin 303 and the third right cabin 304. The three low-pressure water outlets are connected to the third left cabin 303 and the third right cabin 304 through three-branch pipelines. The third left cabin 303 is connected to the fourth left cabin 403 by pipeline. A flow meter is connected to the pipeline between the third left cabin 303 and the fourth left cabin 403. The third right cabin 304 is connected to the fourth right cabin 404 by pipeline. A flow meter is connected to the pipeline between the third right cabin 304 and the fourth right cabin 404.

[0026] The pump body four 8 includes four water inlets of the pump body, four low-pressure water outlets of the pump body and two four high-pressure water outlets of the pump body. The four water inlets of the pump body are connected to the river water through pipelines, and the two four high-pressure water outlets of the pump body are respectively connected to the pipelines of the fourth left cabin 403 and the fourth right cabin 404, and the four low-pressure water outlets of the pump body are connected to the fourth left cabin 403 and the fourth right cabin 404 through three-branch pipelines.

[0027] The specific steps are as follows: Step S1: Pumping water: The four pump bodies (pump body 1 5, pump body 2 6, pump body 3 7, pump body 4 8) work independently, and their water inlets are connected to the river water. When the pump body is started, the pump body extracts water from the river water and pressurizes the water. The pressurized water is divided into two parts: one part is output through the high-pressure water outlet to provide a large and turbulent water flow to the corresponding cabin; the other part is output through the low-pressure water outlet, and after passing through the three-branch pipeline, it provides a small and slow water flow to the corresponding cabin.

[0028] Step S2: Pipeline guidance: The low-pressure pipeline (black line) and high-pressure pipeline (red line) play a guiding role in the system, ensuring that water can flow along the predetermined route. The low-pressure pipeline is mainly used for the passage of small and slow water flows, while the high-pressure pipeline is used for the passage of large and turbulent water flows. The connection between the pipeline and each compartment ensures that water can flow smoothly from one compartment to another.

[0029] Step S3: Cabin storage and distribution: Each cabin (cabin 1, cabin 2, cabin 3, cabin 4) is divided into two parts, left and right, which can store water from the pump body respectively. The pipe connection point between the cabins is equipped with a flow meter to monitor and record the amount of water flowing through the point. According to needs, the water in the cabin can be further distributed to various cabins on the ship through the pipeline.

[0030] Step S4: Overall coordination: The whole system realizes the effective extraction and utilization of river water through the pumping of the pump body, the guidance of the pipeline, and the storage and distribution functions of the cabin. The stability and reliability of the system are ensured through the close coordination between the pipeline and each cabin.

[0031] Step S5: Special function: adjusting the pressure inside each cabin by the pressure pump 9.

[0032] The solutions of the following embodiments are implemented through the above-mentioned pipeline system, and specific adjustments can be made according to specific circumstances.

[0033] Embodiment 2: In this embodiment, based on the pipeline system of embodiment 1, an example is given to illustrate a control method of the pipeline system; During the strength test of the B-type tank, it is necessary to inject water into the different compartments in the B-type tank. This method mainly controls the water level in the compartment through the detection rod, pump body, flow meter, and the pipelines and sealing doors between the compartments; For example: when the No. 1 left cabin 103 needs to be filled with water, the staff inserts the detection rod vertically into the left water inlet 101 of the No. 1 cabin, and starts the pump body 5. The pump body 5 injects river water into the No. 1 left cabin 103 through the high-pressure pipeline. When the detection rod detects that the distance between the horizontal plane in the No. 1 left cabin 103 and the bottom of the cabin is about to reach the required requirement, the pump body 5 is switched to low-pressure pipeline water injection. When the detection rod detects that the distance between the horizontal plane in the No. 1 left cabin 103 and the bottom of the cabin completely reaches the required requirement, the pump body 5 is closed.

[0034] When the horizontal plane inside the No. 1 left cabin 103 and the horizontal plane inside the No. 1 right cabin 104 need to be level, by opening the No. 1 cabin sealing door 105, the water in the No. 1 left cabin 103 enters the No. 1 right cabin 104 through the No. 1 cabin sealing door 105 and reaches levelness.

[0035] When the No. 2 left cabin 203 needs to be filled with water and the No. 1 left cabin 103 needs to be drained, the pipeline connection between the No. 2 left cabin 203 and the No. 1 left cabin 103 is opened, and the river water in the No. 1 left cabin 103 is injected into the No. 2 left cabin 203. When the flow meter between the No. 1 left cabin 103 and the No. 2 left cabin 203 measures that the water flow reaches the required water volume of the No. 2 left cabin 203, or when the water levels in the No. 1 left cabin 103 and the No. 2 left cabin 203 are equal, the pipeline connection between the No. 2 left cabin 203 and the No. 1 left cabin 103 is closed, and the pump body 1 5 is opened to discharge the river water in the No. 1 left cabin 103 into the river through the high-pressure pipeline. When the volume of the river water in the No. 2 left cabin 203 does not reach the required value at this time, water is injected into the No. 2 left cabin 203 by starting the pump body 2 6.

[0036] In this way, each cabin has two or three adjacent cabins. In order to improve the efficiency of water filling, water draining and experiments, at least two cabins are filled with water in each experimental step, and at least two cabins do not touch each other. In this way, each adjacent step involves two adjacent cabins communicating with each other (communication means opening the pipes or sealed doors of two adjacent cabins so that the water in the cabin with relatively high water pressure can flow into the adjacent cabin under the action of pressure), which can reduce the time required for water filling and draining and the energy consumed at one time.

[0037] Based on the above embodiment, the amount of water added to the B-type tank is reduced by regulating the pipeline system and the pressure pump 9, so as to complete the strength test of each tank in the shallow water of the Yangtze River.

[0038] The current method for measuring the strength of the B-type cabin is to only fill the B-type cabin with water, observe the water intake of the B-type cabin, and detect the strength of the cabin wall under the pressure of water. Let the distance from the water level in the cabin to the bottom of the cabin wall be h, and the pressure on the cabin wall is as follows:

[0039] In the formula: is the density of water; g is the acceleration due to gravity; P 气 is the atmospheric pressure; It can be obtained that:

[0040] The method of this experiment changes the pressure in the B-type cabin by compressing the air in the cabin where the pressure pump 9 is located, so that the pressure in the B-type cabin is greater than the atmospheric pressure. It can be obtained that:

[0041] In the formula: P 舱 is the air pressure in the B-type cabin; h1 is the distance from the water level in the cabin of this method to the bottom of the cabin wall.

[0042] Since P 舱 >P 气 So h1 < h, it can be known that the water injection volume into the B-type cabin by this method is less than that of the conventional method, as Figure 5 shown.

[0043] Example 3: Based on the above example, this example provides a method for testing the strength of the B-type cabin under the condition of extremely shallow draft. The specific scheme is as follows: Step S1: Check the strength and airtightness of the cabin walls in the No. 1 cabin 1 and the No. 3 cabin 3 Add water to the No. 1 left cabin 103 and the No. 3 right cabin 304 to a height of 6 meters (from the bottom of the cabin) respectively, and the water injection volumes are about 3100 tons and 3600 tons respectively.

[0044] After the water injection is completed, observe and record the deformation of the cabin wall, and at the same time check whether the weld leaks.

[0045] Other B-type cabins remain in the empty state. As Figure 6 shown, it can be seen from the figure that except for the No. 4 left cabin 403, other cabins are adjacent to the No. 1 left cabin 103 and the No. 3 right cabin 304. On the premise of ensuring the balance of the hull, the time required for adding water to other cabins in the next step is reduced.

[0046] At this time, the forward draft of the ship is 5 meters, the aft draft is 5.6 meters, the cabin wall has no obvious deformation, and the weld has no leakage.

[0047] Step S2: Check the strength and airtightness of the No. 1 cabin 1 and the No. 3 cabin 3 Water is added to the No. 1 left cabin 103 and the No. 1 right cabin 104, as well as the No. 3 left cabin 303 and the No. 3 right cabin 304 to a height of 12.5 meters (from the bottom of the cabin), and the amount of water added is approximately 13,400 tons and 15,400 tons respectively.

[0048] After the water filling is completed, the cargo tank is fully inspected for strength and structural integrity.

[0049] Other B-type tanks remain empty, such as Figure 7 As shown in the figure, it can be seen that each water-added compartment has a compartment without water added adjacent to it. Under the premise of ensuring the balance of the hull, the time of adding water to the compartment without water in the next step is saved.

[0050] At this time, the bow and stern drafts of the ship were both 8.5 meters, the bulkheads had no obvious deformation, the structure was intact, and there was no leakage in the welds.

[0051] Step S3: Check the strength and airtightness of the bulkheads of No. 2 compartment 2 and No. 4 compartment 4 Drain the water from compartment 1 and compartment 3.

[0052] Water is added to the No. 2 left cabin 203 and the No. 4 right cabin 404 to a height of 6 meters (from the cabin bottom), and the amount of water added is approximately 3,100 tons and 3,600 tons, respectively.

[0053] After the water filling is completed, check the strength of the bulkhead and the tightness of the welds.

[0054] Other B-type tanks remain empty, such as Figure 8 As shown in the figure, it can be seen that except for the No. 1 cabin 104, the other cabins are adjacent to the No. 2 left cabin 203 and the No. 4 right cabin 404. Under the premise of ensuring the balance of the hull, the time required for adding water to other cabins in the next step is reduced.

[0055] At this time, the ship's bow draft was 5.5 meters and the stern draft was 6.2 meters. There was no obvious deformation of the bulkhead and no leakage in the welds.

[0056] Step S4: Check the strength and airtightness of the fourth right compartment 404 Water is added to the No. 4 left cabin 403 to a height of 6 meters, about 3,200 tons; water is added to the No. 4 right cabin 404 to a height of 12.5 meters, about 7,300 tons.

[0057] At the same time, the No. 1 cabin 1 and the No. 2 cabin 2 need to be partially filled with water to keep the balance of the ship.

[0058] After the water addition is completed, the strength of the fourth right compartment 404 is checked.

[0059] Other B-type tanks remain empty or properly loaded, such as Fig. 9 shown.

[0060] At this time, the ship's bow draft was 8.2 meters and the stern draft was 8.4 meters. There was no obvious deformation of the bulkhead and no leakage in the welds.

[0061] Step S5: Check the strength and airtightness of the fourth left compartment 403 7,300 tons of water were added to the No. 4 right cabin 404, and 3,300 tons of water were added to the No. 4 left cabin 403; 500 tons of water were added to the No. 1 right cabin 104, and 2,100 tons of water were added to the No. 1 left cabin 103; 3,600 tons of water were added to the No. 2 right cabin 204.

[0062] Other B-type tanks remain empty or properly loaded, such as Fig.10 shown.

[0063] The bow draft is 8.2 meters, the stern draft is 8.4 meters, the bulkhead has no obvious deformation, and the welds have no leakage.

[0064] Step S6: Check the strength and airtightness of the second compartment 2 Water is added to the No. 2 right cabin 204 and the No. 2 left cabin 203 to a height of 12.5 meters, about 7,700 tons each.

[0065] The water in the No. 1 right cabin 104 and the No. 1 left cabin 103 is drained.

[0066] Check the strength of cabin 2.

[0067] Other ballast tanks are maintained in an appropriate loading state as shown in Figure 11.

[0068] At this time, the ship's bow draft was 7.8 meters and the stern draft was 8.2 meters. There was no obvious deformation of the bulkhead and no leakage in the welds.

[0069] The experimental data are as in the above three embodiments, and the following experimental results are summarized: Step S1: The ship's bow draft is 5 meters and its stern draft is 5.6 meters.

[0070] S2: The ship’s bow and stern drafts are both 8.5 meters.

[0071] S3: The ship's bow draft is 5.5 meters and the stern draft is 6.2 meters.

[0072] S4: The ship's draft is 8.2 meters at the bow and 8.4 meters at the stern.

[0073] S5: Bow draft 8.2 meters, stern draft 8.4 meters.

[0074] S6: The ship's draft is 7.8 meters at the bow and 8.2 meters at the stern.

[0075] In the above steps, there was no obvious deformation of the bulkhead of type B cabin and no leakage in the welds.

[0076] By analyzing the above experimental results, the following results can be obtained: During the experiment, the bow draft and stern draft of the ship changed with the increase and decrease of the water volume in the cabin, but always remained within the safe range. This proves that the precise and stable operation of the piping system and pressure control ensures that this experiment can be carried out safely in shallow waters.

[0077] Through the coordinated arrangement of four Type B tanks and experimental steps as well as flexible water adding and drainage operations, the experimental time was effectively saved, which proved the efficiency and practicality of the experimental method.

[0078] At each water adding stage, there was no obvious deformation or weld leakage in the bulkhead, indicating that the bulkhead had sufficient strength and sealing properties.

[0079] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0080] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A strength test method for type B tank under extreme shallow draft conditions, characterized in that: A No. 1 cabin (1), a No. 2 cabin (2), a No. 3 cabin (3) and a No. 4 cabin (4) are arranged on the B-type cabin and are connected in sequence by pipelines, and the No. 1 cabin (1), the No. 2 cabin (2), the No. 3 cabin (3) and the No. 4 cabin (4) are all divided into two left and right cabins, and the left and right cabins are placed side by side on the ship in the experimental waters; The method comprises: Step S1: injecting water into the left compartment of cabin No. 1 and the right compartment of cabin No. 3 to check the strength and air tightness of the inner walls of cabin No. 1 (1) and cabin No. 3 (3); Step S2: injecting water into the No. 1 compartment (1) and the No. 3 compartment (3) to check the strength and air tightness of the No. 1 compartment (1) and the No. 3 compartment (3); Step S3: draining the water in the No. 1 cabin (1) and the No. 3 cabin (3), injecting water into the No. 2 left cabin and the No. 4 right cabin, and checking the strength and air tightness of the walls of the No. 2 cabin (2) and the No. 4 cabin (4); Step S4: filling water into the No. 4 left cabin and the No. 4 right cabin, and filling water into the No. 1 cabin (1) and the No. 2 cabin (2) until the hull is balanced, and checking the strength and airtightness of the No. 4 right cabin; Step S5: swapping the left and right compartments in the No. 1 compartment (1), the No. 2 compartment (2) and the No. 3 compartment (3) to check the strength and air tightness of the No. 4 left compartment; Step S6: Add water to the No. 2 right cabin and the No. 2 left cabin, drain the No. 4 right cabin, keep the No. 4 left cabin unchanged, empty the No. 1 cabin (1), and check the strength and air tightness of the No. 2 cabin (2).

2. A B-type tank strength test method under extreme shallow draft conditions according to claim 1, characterized in that: The pipeline includes a low-pressure pipeline, a high-pressure pipeline and a pump body, the number of the pump bodies is the same as that of the B-type cabins, and the pump bodies correspond to the B-type cabins one by one; In each B-type cabin, a corresponding pump body is connected to the left and right cabins of the corresponding B-type cabin through two high-pressure pipelines, and a corresponding pump body is also connected to the left and right cabins of the corresponding B-type cabin through two low-pressure pipelines, and the pump body controls the water volume of the left and right cabins in the same B-type cabin respectively; In two adjacent different B-type cabins, the cabins on the same side are connected by low-pressure pipelines.

3. A B-type tank strength test method under extreme shallow draft conditions according to claim 2, characterized in that: The above-mentioned pipeline is used to fill and drain water into the type B tank, including the following methods: When a strength test is required for a certain compartment of a type B tank, and when the adjacent compartments of the compartment to be tested are kept in an unloaded state, the pump corresponding to the type B tank where the compartment is located is started, and the pump is connected to inject water into the compartment through a pipeline, and the water injection amount of each compartment is controlled. When the water in the compartment is about to reach the required water level, the output power of the pump is reduced, and the pump is injected into the compartment through a low-pressure pipeline until the water in the compartment reaches the required water level, and the strength test of the corresponding compartment is completed; When it is necessary to drain the cabin that has completed the test and conduct a strength test on its adjacent cabin, the valve of the pipeline between the two adjacent cabins is opened, and the water in the cabin to be drained is injected into the cabin to be tested under the action of pressure. When the water pressure in the two cabins is equal or the water in the cabin to be tested reaches the required water level, the valve of the pipeline between the two cabins is closed, and the corresponding pumps of the two cabins are started. The pumps are filled and pumped to make the water level in the corresponding cabins reach the test requirements, and the strength test of the corresponding cabins is completed.

4. The strength test method for type B tank under extreme shallow draft conditions according to claim 1 is characterized in that: Before step S1, the method further includes: Step S 01 : Before the test, all compartments are kept empty, and the draft of the hull is measured and recorded; Step S 02 :It is known that the maximum pressure carried by the B-type tank during operation is P1. It can be known that the rated height of the horizontal plane in the B-type tank from the bottom of the tank should be h. The weight of the water in the tank is calculated to be m1, and the rated draft is obtained as L. When L is less than or equal to the water depth of the water area, the required pressure in the tank during the test is P1; when L is greater than the water depth, the required pressure in the tank during the test is P1+△p, and △p is the pressure that needs to be increased in the tank during the test. △p is proportional to the difference between the water depth and L. At this time, the rated height of the horizontal plane in the B-type tank from the bottom of the tank should be h1, and the weight of the water in the B-type tank is m2; Step S 03 :Adjust the pressure in the cabin according to the test plan. When the pressure in the cabin is adjusted to P1+△p, start the test.

5. A B-type tank strength test method under extreme shallow draft conditions according to claim 4, characterized in that: The adjusting the pressure in the cabin according to the test plan includes: A pressure pump (9) is fixedly connected to the interior of each left and right cabin of the B-type cabin, and the pressure in the cabin is adjusted by compressing the air in the cabin by the pressure pump (9).

6. The B-type tank for the strength test of the B-type tank under the extreme shallow draft condition according to claim 3, characterized in that: The water volume of the left and right compartments in the same B-type cabin is controlled separately, including: The No. 1 tank (1) comprises a No. 1 tank body (106), and a No. 1 bulkhead (107) is fixedly connected inside the No. 1 tank body (106) to divide the interior of the No. 1 tank body (106) into a No. 1 left cabin (103) and a No. 1 right cabin (104), so that water in the left and right cabins of the No. 1 tank body (106) is not inter-connected; The water in the tank to be drained is injected into the tank to be tested under pressure, including: The No. 1 cabin (1) further comprises a No. 1 cabin sealing door (105), and the No. 1 cabin sealing door (105) is provided on the No. 1 bulkhead (107), and the No. 1 cabin sealing door (105) is controlled to be opened so that water in the cabin to be drained can be injected into the cabin to be tested; The pump body injects water into the cabin through a pipeline, including: A No. 1 left water inlet (101) and a No. 1 right water inlet (102) are provided above the No. 1 tank body (106), and water is injected into the No. 1 left cabin (103) through the No. 1 left water inlet (101) connected to the pipeline of the pump body (5), and water is injected into the No. 1 right cabin (104) through the No. 1 right water inlet (102) connected to the pipeline of the pump body (5).

7. The B-type tank used for the strength test of the B-type tank under the extreme shallow draft condition according to claim 6, characterized in that: Calculate the weight of the water in the hold, including: It is known that the internal volume of the B-type cabin is C and the internal height is α. By setting the left and right cabins in the B-type cabin to the same shape, the volume of each cabin is , get the .

8. The B-type tank used for the strength test of the B-type tank under the extreme shallow draft condition according to claim 7, characterized in that: Control the water filling rate of each compartment, including: Liquid level detectors are arranged in the left and right compartments of the B-type tank, and the depth of water in the compartment is detected by the liquid level detectors. When the water depth required for the water test is reached, an alarm is sounded to request the staff to stop injecting water.

9. The piping system for the strength test of type B tank under extreme shallow draft conditions according to claim 2 is characterized in that: Control the water filling rate of each compartment, including: A thick and rapid water flow is injected into the corresponding compartment through the high-pressure pipeline. When the required water volume is about to be reached, a thin and slow water flow is injected into the corresponding compartment through the low-pressure pipeline until the required water volume is reached.

10. The piping system for the strength test of type B tank under extreme shallow draft conditions according to claim 2, characterized in that: The pipeline fills and drains water into the cabin, including: The pump body is provided with a pump body water inlet, a pump body low-pressure water outlet and two pump body high-pressure water outlets. The pump body water inlet is connected to the pipeline of the water area, and the pump body low-pressure water outlet is connected to the left cabin and the right cabin of the corresponding B-type cabin through a three-branch pipe pipeline, so that each of the pump body high-pressure water outlets is connected to the left cabin and the right cabin pipeline of the corresponding B-type cabin, and finally the B-type cabin is pumped and drained through the pump body.

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