• Ocean Systems Engineering
• /
• 제6권1호
• /
• pp.99-115
• /
• 2016

In meeting the technical needs for deepwater conditions and overcoming the shortfalls of single-layer pipes for deepwater applications, pipe-in-pipe (PIP) systems have been developed. While, for PIP pipelines directly laid on the seabed or with partial embedment, one of the primary service risks is lateral buckling. The critical axial force is a key factor governing the global lateral buckling response that has been paid much more attention. It is influenced by global imperfections, submerged weight, stiffness, pipe-soil interaction characteristics, et al. In this study, Finite Element Models for imperfect PIP systems are established on the basis of 3D beam element and tube-to-tube element in Abaqus. A parameter study was conducted to investigate the effects of these parameters on the critical axial force and post-buckling forms. These parameters include structural parameters such as imperfections, clearance, and bulkhead spacing, pipe/soil interaction parameter, for instance, axial and lateral friction properties between pipeline and seabed, and load parameter submerged weight. Python as a programming language is been used to realize parametric modeling in Abaqus. Some conclusions are obtained which can provide a guide for the design of PIP pipelines.

• 한국산업융합학회 논문집
• /
• 제23권6_2호
• /
• pp.1081-1091
• /
• 2020

The most recent issue of offshore plants that produce oil and gas are the decommissioning engineering of aged or discontinued platforms. There are many platforms that are being dismantled in the United States, Europe, and areas in Southeast Asia. In particular, more than 400 old platforms in Southeast Asia (Indonesia, Malaysia) are preparing to dismantle. They are spread out across Southeast Asia with a water level of 50 meters and small-scale of less than 10,000 tons. However, this offshore plant decommissioning market is a very suitable market for small and medium-sized shipyards in Korea to enter with their established equipment and engineers. Platform decommissioning is conducted according to decommissioning procedures. However, there are some difficulties in market advances as no developed case studies or process models are established on how platform structures and components are to be dismantled and how the dismantled material is to be reused and recycled. Therefore, this study presented domestic and foreign regulations on the reuse and recycling of oil and gas producing offshore plant platforms, case analyses on developed decommissioning engineering, platform reuse and recycling guidelines, and platform and pipeline decommissioning processes and methods.

• 한국해양공학회지
• /
• 제28권1호
• /
• pp.85-92
• /
• 2014

Offshore fields are increasingly important for the development of offshore resources due to the growing energy needs. However, an offshore field for oil and gas production has difficult development conditions, e.g., high temperature, high pressure, sweet/sour compositions of fluids, etc. Corrosion is one of the biggest issues for offshore pipeline engineering. In this study, a Corrosion Resistant Alloy (CRA) pipe for corrosion prevention was investigated through its global demand and trends, and three types of CRA pipelines were introduced with detailed explanations. The usefulness of CRA was also evaluated in comparison to a carbon steel pipeline in terms of the structural strength, cost, and other factors. Offshore pipeline engineering, including mechanical design and verification of the results through an installation analysis based on numerical software, was performed for the carbon steel type and solid CRA type. The results obtained from this study will be useful data for CRA pipeline designers and researchers.

• 한국농공학회지
• /
• 제41권6호
• /
• pp.64-74
• /
• 1999

The frequency of earthquake occurrence tends to increase in Korea. Therefore, the stability of pipeline, such as watersupply pipe, gas pipe, and oil pipe etc. across fault zones in Gyoung-sang landmass is very important, expecially , in metropolitan area. There were some examples of the construction of buried pipeline across fault zones in Korea. the interactiion between the buried pipeline across fault zones and the ground is considered. As well, in the interfaces of them, the direct shear numerical analysis model including elasto-plastic joint element is assumed that the retained dilatancy theory in them, otherwise. Also, the other elements are modeled the ground is nonlinear elastic coutinuaus beam, respectively. In this study, the maximum shear force point exist inside retaine zone(anchored zone) during shwar (as fault sliding), and the distribution of pipeline's behavior is all alike them of pipeline buried in ladnsliding grounds. Since the pipeline is not continuous beam but jointed by steel-pipe segments , practically, on acting of a large bending moment or a shear force, then, those are may be unstable. The reaearch on this point may be new approach.

• 대한조선학회 특별논문집
• /
• 대한조선학회 2009년도 특별논문집
• /
• pp.24-34
• /
• 2009

The latest trend of development for submarine oil field is caused by the drained oil and gas for ground field, and FPSO is a keyword as the development for submarine oil field. FPSO (Floating Production Storage Offloading) is a kind of vessel type have a topside system for production of oil and gas and store them until the oil or gas can be offloaded onto a tanker or transported through a pipeline. Prior to the introduction of reinforcement under the pull-in winch on the STP extended top as the object of this paper, the technical background shall be introduced such as FPSO and the system and main equipments for STP as follows. The original structural concept for reinforcement of pull-in winch on the STP top and extended structure on moonpool was proposed by buyer's engineering team but it was much modified and improved in accordance with builder's fabrication and construction method.

• 한국해안해양공학회지
• /
• 제11권1호
• /
• pp.1-6
• /
• 1999

해안 및 해양에 설치되어 있는 해저관로는 원유, 가스, 물과 이들의 혼합된 유체들을 전달하기 위한 수단으로 사용되고 있다. 관로 내부 유체의 열과 압력 차이는 해저관로의 팽찰을 야기시킨다. 해전관로 팽창은 관로와 연결되는 구조물들에 응력을 유발시킨다. 작용 응력이 연결 부재의 항복점을 초과하거나 전체 시스템의 허용변형을 초과할 경우 구조물에 손상이 발생된다. 해안 및 해양에 설치되는 해저관로는 주로 위험 물질이나 유독 유체를 포함하기 때문에 만약 이런 유체의 유출이 발생될 경우 인명 피해는 물론 큰 경제적 손실을 가져온다. 비록 해저관로는 시간적/공간적 제약 없이 유체를 전달할 수 있지만, 이런 관로 설계시 안전하게 그 기능을 수행할 수 있도록 고려되어야 한다. 본 논문에서는 해저관로의 열변형 해석에 사용되는 여러 개의 이론을 조사하였고, 관로의 요소들이 관로 팽창에 미치는 영향에 대해 조사하였다.

• 한국가스학회지
• /
• 제21권2호
• /
• pp.10-19
• /
• 2017

본 연구에서는 캐나다 오일, 가스 사업의 현황과 특성들을 분석하고 이를 기반으로 오일, 가스 개발 및 생산을 위한 광권, 광구 투자의 개략적인 가이드라인을 제시하였다. 캐나다 서부 퇴적분지는 11개 정도의 주요 지층으로 구분되는데 이중 몬트니, 카디움, 바이킹, 바켄 지층을 중심으로 개발이 진행되고 있다. 하지만 2014년 이후 지속된 저유가로 캐나다 내 시추는 2016년 1분기 기준 총 1,917공이 수행되어, 2014년 1분기의 5,724공, 2015년 1분기의 3,365공에 비하여 각각 67%, 43% 감소하였다. 또한, 저유가의 영향으로 오일, 가스 광구 거래 가격은 매장량 및 생산량 기준 평균 2011년 최고치 대비 34~47% 감소하였고, 개발을 위한 앨버타주 광권의 입찰금액, 입찰면적, 단위 면적당 입찰 가격은 2011년 최고치 대비 평균 81~97% 감소하였다. 이런 이유로 국내 기업의 캐나다 석유사업 진출이 매우 유리한 상황이고, 특히 대규모 투자가 요구되는 광구 매입에 비하여 소규모 투자로 오일, 가스 사업 진출이 가능하고 광구가격 대비 하락폭이 매우 큰 광권 확보가 가능한 최적 시기로 판단된다.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2000년도 추계학술대회 논문집 학회본부 C
• /
• pp.503-505
• /
• 2000

In general, the reason of the abnormal corrosion on oil tanks has been proved the MIC (Microbiologically Influenced Corrosion). The concern about MIC is increasing more and more now days. Therefore, this paper presents the results of basic study on the Microbiologically Influenced Corrosion of gas pipeline running parallel with 22.9kV D/L (Distribution Line).

• 설비공학논문집
• /
• 제16권9호
• /
• pp.863-871
• /
• 2004

The use of fossil fuels like coal, oil and natural gases around the world causes an increase of the carbon dioxide content in the atmosphere. In order to reduce the concentration of the greenhouse gas, the idea of carbon dioxide sequestration in the ocean is proposed to be an effective mitigation strategy to counteract potential global warming due to the greenhouse effect. Therefore, in the present study, calculations of the dissolution behavior of carbon dioxide when liquid carbon dioxide is released at 1,000m and 1,500m in depth by fixed pipeline are performed. The results show that carbon dioxide droplets change to carbon dioxide bubbles in gas phase around 500m in depth, and the droplets are completely dissolved below 500 m in depth if the liquide carbon dioxide is released both at 1,000 m in depth with the initial diameter of 0.007m or less and at 1,500m in depth with the diameter of 0.011m or less.

• 한국해양공학회지
• /
• 제31권3호
• /
• pp.227-232
• /
• 2017

Subsea pipelines are one of the most important structures used to transport fluids such as oil and natural gas in offshore environments. The uplift behavior of the pipeline caused by earthquakes and buoyancy can result in a pipeline failure. The objective of this study is to examine the peak uplift resistance through parametric studies with numerical modeling by PLAXIS 3D Tunnel. The effects of the embedment ratio and pipe diameter were first examined for uplift resistance in sand and soft clay conditions. Then the length of geogrid layers and the number of geogrid layers were examined in terms of ability to resist uplift behavior.