• Title, Summary, Keyword: 파주력

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주묘 사례를 통한 AC-14형과 ASS형 앵커의 파주계수 비교에 관한 연구

  • Gong, Gil-Yeong;Lee, Yun-Seok;Jeong, Chang-Hyeon;Kim, Jong-Seong
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • pp.340-342
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    • 2011
  • 묘박 중인 선박은 주묘를 예방하기 위해서는 파주력을 크게 유지해야 하는데, 대부분의 파주력은 앵커에 의해 형성된다. 앵커의 파주력은 앵커의 형태와 수중무게 그리고 해저 저질에 따른 파주계수에 따라 달라진다. AC-14형 앵커는 ASS형 앵커에 비하여 2~2.5배의 파주력을 형성하는 것으로 알려져 있다. 그러나 이러한 파주계수는 모형실험 등을 통하여 정해진 것으로 실제 상황에서 그 유효성을 분석한 연구는 거의 없다. 따라서 본 논문에서는 AC-14형 및 ASS형 앵커의 파주계수를 실제 선박에서의 주묘 사례를 분석하여, 현재 사용되고 있는 파주계수의 유효성을 확인하였다.

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Model Experiments for the Coefficients of Holding Power of the Hall`s Type Anchor and a Chain Cable (Hall 형 묘 및 묘쇄의 파주력 계수에 관한 모형실험)

  • Kim, Se-Won;Kim, Ki-Yun
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.27 no.2
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    • pp.97-104
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    • 1991
  • Generally, the coefficients of common holding power of an anchor and a chain cable have been reported too higher in their values in the safety of the shiphandling. The model experiment was carried out to find the most suitable coefficients of holding power of the Hall's type anchor and the chain cable in various kinds of seabed. The results obtained are summarized as follows; 1) The coefficients of holding power of the anchor and the chain cable were 4.05, 0.75 in the mud, 3.95, 0.66 in the sand and 3.61, 0.72 in the pebbles respectively. 2) The experimental coefficients of holding power of the anchor and the chain cable were 0.4~0.6 times the values of the coefficients of common holding power. They were almost same as the values of the coefficients of safe holding power in the mud and the sand, but in case of the pebbles, they were 1.4~1.8 times the values of the coefficients of safe holding power. 3) It is considered useful for the safety of the shiphandling to draw curves of the holding power with maximum limits holding power at the various wind forces and the coefficients of holding power.

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A Study on Anchor holding power and Anchor holding Coefficient (Focus on Naval vessel) (묘(錨)의 파주력과 파주계수에 관한 고찰(해군 함정을 중심으로))

  • Lim, Bong-Taek;Kim, Byoung-Suk
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • pp.23-24
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    • 2013
  • 본 연구에서는 해군함정에서 투묘 시 함정별 묘의 파주계수와 그에 파주력 그리고 외력의 세기를 고려한 묘쇄의 적정 신출량을 구할 수 있는 수리모델을 정립하여 제시하고, 이것을 해군이 보유하고 있는 전 함정 승조원들로 하여금 쉽게 사용할 수 있는 적정 묘쇄 신출량을 그래프한 자료를 제시하였다. 본 연구 결과는 해군함정이 투묘시 바로 적용될 수 있을 뿐만 아니라, 이론적인 근거를 제공하는 참고자료로 유용하게 활용될 수 있을 것이다.

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A Study on Theoretical Consideration to the Holding Power and Holding Power Coefficient of War Ship Anchor (함정 묘의 파주력과 파주계수에 대한 이론적 고찰에 관한 연구)

  • Lim, Bong-Taek;Ko, Jae-Woo;Kim, Byoung-Suk
    • Journal of Navigation and Port Research
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    • v.39 no.1
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    • pp.1-6
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    • 2015
  • In this study, with the awareness of the limitations set in the currently operated calculations of holding power and the holding power coefficient of anchors of naval ships due to its simple application of a specific value, various factors that impact the holding power and its coefficient were verified based on existing data analysis of literature research and numerous experiment results from anchor manufacturers, research institutes and academic community in order to overcome the aforementioned limitations. In addition, holding power and holding power coefficient were compared and analyzed by the shape of anchors. As a result, we came to know that the holding power of AC-14 type anchor is stronger than that of ASS type anchor or U.S. Navy Standard type anchor which makes it possible to reduce the weight of the anchor and therefore ease the process of naval shipbuilding. Furthermore, we confirmed the fact that U.S. Navy Standard type anchor does not react sensitively to the weight change of the anchor. Lastly, we found out that Danforth type anchor's holding power coefficient is in inverse proportion to the weight. Moreover, instructions for managing anchor are arranged easily for your information. The results of this study is expected to provide anchor - operating naval crew with a reliable theoretical basis pertaining to an anchor's holding power and its coefficient and contribute much for the safety of their act of anchoring.

A Study on the Holding Power Coefficient of AC-14 type and ASS type Anchor in Actual Ships (주묘 사례를 통한 AC-14형과 ASS형 앵커의 파주계수 비교에 관한 연구)

  • Jung, Chang-Hyun;Lee, Yun-Sok;Kim, Jong-Sung;Kong, Gil-Young
    • Journal of Navigation and Port Research
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    • v.35 no.8
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    • pp.613-618
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    • 2011
  • Vessels on anchoring are sometimes dragged due to the increased external forces. For preventing the dragging, it is required to enhance the holding power of the anchor. The holding power depends on the type and weight of the anchor and the seabed condition. Especially, the holding power of AC-14 type anchor is known to be 2~2.5 times bigger than that of ASS type anchor. However, these coefficients was determined nearly by the result of the model test, so there is a need to verify that by sea trial. Therefore actual dragging case was analyzed and then compared with the coefficients in use, it was found that the two of them are much alike.

Experimental Investigation on the Embedding Motion and Holding Power of Anchor According to Initial Position (앵커의 초기 투묘 상태에 따르는 파주운동과 파주력 특성에 대한 실험적 연구)

  • Lee, Sang-Min;Lee, Jin-A
    • Journal of Navigation and Port Research
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    • v.38 no.6
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    • pp.683-688
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    • 2014
  • The vessel should prevent dragging anchor against the external forces by utilizing the anchor and secure the stability of it. A fundamental understanding on the embedding motion and holding power of the anchor is necessary to perform the safe operating of anchor work. In this study, the embedding motion and holding power of the anchor according to an initial position in an experimental tank of 6m long in sand are tested by using two types of different anchor models(ASS and AC-14), which are generally applied to the commercial vessel nowadays. The anchor flukes seem to rotate and to be embedded into soil up to the maximum depth and maintaining a constant depth in case of the same direction and perpendicular to the towing direction, regardless of the form of an anchor. In case of the opposite direction to the towing direction, it is noted that the coefficient of holding power becomes smaller than the other initial positions.

The Model Experiment on Holding Power of the Anchors used in the Set Net (정치망 고정용 닻의 파주력에 대한 모형실험)

  • 윤일부;이주희;권병국;김성훈;신정욱
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.37 no.2
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    • pp.95-105
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    • 2001
  • A series of experiment is carried out to determine the holding power of the existing anchors used in the stationary gear in the coast of the South sea. The experiment apparatus is made of the pulling machine, the load cell, the personal computer and three water tanks the bottom of which are mud, sand and m & s respectively. The result obtained are as follows : 1. On the tension and holding power of the existing anchors, B-type of the stock anchor with two fluke shows the greatest and gets smaller on order of A-type one with a fluke. The holding power of the anchors shows the greatest in the mud and gets smaller in order of m & s, sand. And, the holding power depending upon the length of anchor rope increase as the length does up to the 4 times of depth. 2. On the holding power per fluke area of the existing anchors in case of ration of length of anchor rope to depth is 2, 3 and 4, A-type anchor shows about 310-320 kg/m supper(2), 470-480 kg/m supper(2), 590-640 kg/m supper(2) respectively, B-type one 260-265 kg/m supper(2), 390-450 kg/m supper(2), 630-700 kg/m supper(2) respectively, and C-type one 70-100 kg/m supper(2), 150-180 kg/m supper(2), 210-270 kg/m supper(2) respectively. The holding power per fluke area of the anchors increase as the length of anchor rope does. 3. On the coefficient of holding power of the existing anchors, A-type anchor shows the greatest and gets smaller in the order of B-type one, C-type one.

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A Study on the Anchoring Safety Assessment of E-Group Anchorage in Ulsan Port (울산항 E 집단정박지 묘박안전성 평가에 관한 연구)

  • Lee, Yun-Sok
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.20 no.2
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    • pp.172-178
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    • 2014
  • This study suggests the minimum critical external forces based on the assessment of anchoring safety to single anchor situation for representative 8 number of ships in E-group anchorage of Ulsan port. Assessment of anchoring safety is compared holding powers of anchor with external forces of wind, wave and current. Holding powers was reflected materials of seabed, equipment numbers regarding anchor and chain weight, also external forces acting on a hull was calculated considering projected wind area and wetted surface area to the full and ballast conditions respectively. The results of anchoring safety assessments to single anchor showed that the minimum criteria of dragging anchor is a little different from ship's type, size and loading conditions. Bulk carrier can be dragged over the 15m/s of winds and Tanker can be dragged over the 13m/s of winds in case of less than 2knots of currents speed.

Analysis of Wave Load and Mooring System for Ocean Monitoring Facilities - About an estimation method for horizontal force of circular pile in sand - (해상관측시설을 위한 파랑하중과 계류계 해석 -모래중에 뭍힌 원형파일의 수평력 추정방법을 중심으로-)

  • Yoon Gil Su;Kim Yong Jig;Kim Dong Joon;Kang Sin Young
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.1 no.1
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    • pp.102-111
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    • 1998
  • Ocean monitoring facilities are divided into two types, fixed type and floating type. This paper deals with wane load calculation and mooring system for a floating monitoring facility. Wave load and drift forces are calculated for an example case of floating monitoring buoy To enlarge holding power of anchor, circular pile model test was performed. A program for horizontal force of circular pile in sand was made and the calculated result showed fairy good agreement with the result of model test. It is expected that this method will provide good estimation for the holding power of the prototype of circular pile anchor which is relied upon SCUBA activity for installation.

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VTS 해역에서 주묘 사례를 통한 주묘 위험성 판단 프로그램의 활용과 시스템 개선방안에 관한 연구

  • Im, Se-Uk;Ji, Min-Gu;Jeong, Chang-Hyeon;Kim, Ju-Seong
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • pp.1-3
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    • 2019
  • 최근 선박의 대형화, 태풍 및 돌풍 등 급격한 자연환경의 변화, 한정된 정박지의 과밀 등으로 VTS 해역에서 선박 주묘가 자주 발생하고 있다. 선박의 주묘를 예측하기 위해서는 기상 조건에 의한 외력과 선박의 묘, 묘쇄 등 대항력의 정확한 비교, 현수부 및 파주부를 고려한 주묘 발생 가능 시점 예측 등의 노력이 요구된다. 본 연구에서는 VTS 관제 구역에서의 주묘 사고 사례 분석을 통하여 주묘 위험성 판단 프로그램을 검증하고, 관제 시스템에서 활용을 위한 시스템 개선 방안을 제안하고자 한다. 향후 관제 시스템의 주묘 위험성 판단 기능 도입을 통하여 주묘 사고의 예방 및 조기 대응이 가능할 것으로 기대한다.

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