50톤급 세관감시정의 운항성능 개선에 관한 연구

Abstract

This study is the enhancement of safe maneuvering for customs patrolboat of 50 tons class that customs services possess. That is, this study analyzes safe maneuvering for the ship of BUSAN365(Ship Number) of 50 tons class which is disposed at Kamchun Port, Busan.

We exchange a lot of goods with foreign country throughout the international oversea trade, but a few still smuggle in the way of illegal method.

So in chapter one(1) described the roles and objectives of customs patrolboat to ban smuggling.

In chapter 2 introduced the characteristics of the customs monitoring station, and surveillance section. Also this part explains the roles, service management and the improvement of the patrolboat of advanced maritime countries(Unite State of America, Japan, Netherlands, Hongkong, Singapore etc). Especially, with these advanced countries strengthening the ability of information analysis, they preponderantly enlarge information ability of ships and cargoes. Therefore they concentratedly input their patrolboat into the dangerous elements and utilize flexibly a surveillance. That is, we can know they positively operate maneuvering surveillance system.

In order to perform this task successfully, first of all we must secure safe maneuvering of patrolboat. So in this study I evaluated characteristics of safe maneuvering for customs patrolboat of 50 tons class on the base of characteristics for the stability in regular wave.

In chapter 3 and 4, I compared and contrasted ship stability with passenger ship and customs patrolboat on the base of the Ship Safe Act to examine safe maneuvering of ship. And I analyzed a variety of the data from the heeling test and sea trial test of the customs patrolboat of 50 tons class. Besides I carried out the motion calculation of the customs patrolboat from the N.S.M(New Strip Method) simulation that the customs patrolboat motion speciality based on ocean environmental condition. From this calculation, considered that their customs patrolboat average speed in voyage, and I also grasped the hull to use 6 free motion in adjusted which those items are wave-length, wave-high and wave attack angle turned into variable function to use compared respectively analyzed.

In conclusion, we got the following results through the data from heeling test for stability and sea trial test for maneuvering ability and data from many kind of prints and also the results of N.S.M. simulation carried out in various sea status conditions for the safe maneuvering ability of the customs patrolboat.

Firstly, The GM of customs patrolboat needs to 0.354m under status of Lightship condition, Full load departure condition and Full load arrival condition according to stability rules of the ships Safety Act. But the results of this ship heeling test showed that in Lightship state was 1.761m, Full load departure state was 1.530m and Full load arrive was 1.638m, it means 4.3～5 times higher than that values of the rule of the Ships Safety Act. Generally speaking, in case of merchant ship GM is appropriate for 3% more or less in ship's breadth, therefore customs patrolboat GM are too excessive respectively.

Secondly, According to the analysis from the results of the N.S.M. simulation program for customs patrolboat in motion characteristics, among the abreast motion, Heaving was scored high, while during in the rotating motion, Rolling was most high. Especially, respondence of Rolling movement was the most high at the about 90° of wave attack angle against centerline and wave-length is almost same as the LOA(λ/L≒1), maximum Rolling was 40°.

Finally, From customs patrolboat in stability and moving characteristics during navigation in the smooth water area of harbor, the test results showed enough to navigate safely with good stability. But if wave-length is more than 2.5m and the ratio(λ/L) of LOA and ship-width is nearly 1.0, it will have severe possibility of Rolling and Heaving, so in this case do not guarantee ship's safe stability under normal ship's speed. Therefore when this vessel navigates in the open sea state, which needs to research and analyze systematically through vessel valued method after from this days.