The Key Technologies Research On Ship's Emergency Plugging Device

With the increasing water transport trade,more ship accidents happened,and these not only cause many huge economic losses to the owners,but also bring the irreversible damage to the environment.It is urgent to find an effective way to solve the emergency,which can quickly deal with the problem after a ship accident happened,and keep the cruising ability of ship,to race against the precious time for recovering work,as well as to avoid damaging the environment.Through studying the state of the damaged ship,this thesis proposes a plugging device design scheme with the modular and magnetic adsorption method,whose single biggest block area is 2.25 square meters;assembly block width 1.5 meters,large holes with 10 meters or so.The plugging device consists of four parts,namely adsorption,support,connection and sealing,whose single part is the chain type,then can be rolled and unfolded.To adjust the device when it is laid and easily to disassembly after using,the design gets a permanent magnetic suction regulator,and the adsorption force of the permanent magnets can be changed through adjusting the distance between permanent magnets and the ship.On the device,the permanent magnets adsorbs the surface of ship,therefore the choice and arrangement of the permanent magnets need to be designed reasonably.The paper is based on the theory of electromagnetic mirror and molecular circulation theory to calculate the cuboid permanent magnetic force,and get the influence law that the dimensions of the cuboid permanent magnets to its adsorption force.Through the control variable method,researching the combined magnets' work by experiment,to get the curve relation between three variates(the distance between the permanent magnets,the distance between permanent magnet and armature,the thickness of the yoke iron)and magnetic force caused by magnetic circuit,according to the conclusion of this experiment,the arrangement of magnetism masses of the largest magnetic attraction force are seen,then design the magnetic circuit,and make the permanent magnets the best working state,and ensure safe and reliable adsorption when it is working.In this paper,we analyze the working condition of the plugging device,and get the computing method of water inflow when the damage is large and small holes respectively,combining the simplified model in working state,the water resistance caused by laying the device can be calculated;after laying,can calculate the water resistance of the device under different navigable speed,and based on this,we can verify the key parts of the device,then learn about the safety and reliability of the design.