Research On Wave Compensation Boat-lifting System

Life-saving appliances are statutory safety equipments in ships, while lifeboat and boat-lifting devices are the important parts of the life-saving appliances which take the important responsibility of keeping the persons from the danger in emergence. With the growth of our country's shipping trade and ocean exploitation, as one kind of important life-saving appliances, the lifeboat's performance and reliability of the boat-lifting device draw more attention. In many times, life-boats should be lifted at complicated and abominable sea state. In this condition, sea-wave affects the life-boats and the boat apparently, which makes the growth of danger and difficulty of boat-lifting. It puts forward higher demand on boat-lifting device, such as adding the function of wave compensation. External research and exploitation in this field began from 1980's, and our country's research is later, there is long distance to catch up with the oversea research. In order to accelerate the development of our countries' ship-building industry, it is necessary to take deep research on this subject.This paper takes research on boat-lifting device system which is used at abominable sea state, and finds that it should be compensate the effect on lifeboat caused by the wave in order to realize the safety lifting at abominable sea state. The purpose of wave compensation is to alleviate the influence on lifeboat. It is necessary to keep the falls tight in order to realize the wave compensation by keeping the constant tension of the falls. According to comparing the structure and the performance of many kinds of boat-lifting device, this paper gives the structure of the davit and wave compensation way which realize the safety lifting at abominable sea state. Then it analyses the wave's movement and technical quota of boat-lifting device at abominable sea state which supply the foundation to the following design of wave-compensation boat-lifting winch. Taking some lifeboat for example, this paper analyses and computes the boat-lifting winch in detail and designs the wave compensation boat-lifting winch system, at the same time chooses the components. By building some parts of model and simulating, it proves that the designed system has good performance and realizes wave compensation at abominable sea state, so it can promise the safe recovery of the lifeboat. This paper gives theory basis to the exploitation of the wave compensation boat-lifting winch.