• Journal of the Korean Institute of Gas
• /
• v.26 no.5
• /
• pp.49-57
• /
• 2022

If the hydrogen industry is activated in the future, the LH2 receiving terminal with membrane storage tank is a major way to store and send large capacity hydrogen. Since such a LH2 receiving terminal does not currently exist, the process simulation model of it was completed by referring to the design data on existing LNG receiving terminal with same typed storage tank. Based on this model, the amount of BOG generation according to change of design conditions, which is a very important factor in the operation of LH2 receiving terminal, was predicted. Through this, it was attempted to review the appropriate operating conditions to minimize the amount of BOG generated during unloading in LH2 receiving terminal with membrane storage tank.

• Journal of Welding and Joining
• /
• v.14 no.1
• /
• pp.99-106
• /
• 1996

Development of an automatic TIG welding system incorporating a vision sensor and torch control mechanism leads to an improved welding quality and greater production efficiency. The automatic welding system should be greatly restricted in its size and weight for the LNG(Liquefied Natural Gas) storage tank and also provide a unique torch rotating mechanism which keeps the torch tip in the constant position while the angle is changed continuously to maintain the welding torch substantially perpendicular to the weld line. The developed system is driven by two translation axes X, Z and one rotational axis. A moving line window method is adopted to the image recognition of the corrugated membranes with specular reflection. This method decides original laser stripe patterns in image which is affected by multi-reflection. A self-teaching algorithm, which guides the automatic welding machine with the information provided by the CCD camera without any previous learning of a reference trajectory, was developed for tracking the corrugated membrane of the LNG tank along the weld line.

• Journal of the Korean Society of Industry Convergence
• /
• v.24 no.6_2
• /
• pp.787-793
• /
• 2021

The global demand for Liquefied Natural Gas(LNG) continues to increase and is facing a big cycle. To keep pace with the increase in international demand for LNG, the demand for LNG fueled ships is also increasing. Since LNG fuel tanks are operated in a cryogenic environment, insulation technology is very important, and although there are various types of insulation applied to Type C tanks, multi-layer insulation and vacuum insulation are typically applied. Powder insulation materials are widely used for storage and transportation of cryogenic liquids in tanks with such a complex insulation structure. In this study, compression tests at room and cryogenic temperature were performed on closed perlite, glass bubble, and fumed silica, which are representative powder insulation material candidates. Finally, the applicability to the Type C fuel tank was reviewed by analyzing the experimental results of this study.

• Advances in concrete construction
• /
• v.16 no.5
• /
• pp.231-241
• /
• 2023

The purpose of this study was to evaluate the practical application of high-flowing concrete for a steel-concrete panel (SCP) module for a liquefied natural gas (LNG) storage tank. We evaluated the physical properties and filling performance of the developed concrete for the SCP module. First, slump tests were performed to evaluate the performance of the proposed standards for the filling tests. All the concrete mixes showed satisfactory performance. Based on the results of the previous study, the reliability of the required time measured using the T₅₀₀ test and the rheometer results measured before and after pumping was 0.94, indicating that segregation and blocking should not occur. L-box and U-box tests were conducted before and after pumping. All the recommended standards showed satisfactory performance. The SCP structural module for LNG storage tanks was fabricated to a full scale to evaluate its practical application at the final site. Satisfactory filling performance was confirmed for all the specimens.

• Journal of Welding and Joining
• /
• v.15 no.4
• /
• pp.116-125
• /
• 1997

Electron beam weldability of 9%Ni steels has been investigated to apply EBW to the construction of LNG storage tank. While mechanical properties of welded joints were satisfied by ASTM specification, impact energy of weld metal was as low as 27 - 55J at $-196^{\circ}C$. As the result of Ni wires inserted at the joint to be welded, Ni content of weld metal was increased to about 10%, resulting on the improvement of impact toughness to 110 ~ 120J at $-196^{\circ}C$. This improvement of impact toughness in weld metal was due to the formation of tempered martensite and retained austenite. Above results indicate that, if Ni content of weld metal was increased about 10% by Ni wires addition, electron beam welded 9%Ni steels weld metal had sufficient impact energy necessary for a LNG storage tank.

• Journal of Welding and Joining
• /
• v.31 no.1
• /
• pp.21-25
• /
• 2013

Aluminum alloy, Al5083-O, is one of candidate materials for the LNG storage tank, because of its excellent weldability, cryogenic characteristics, and corrosion resistance. The good weldability of Al5083-O is very important in LNG storage tank manufacturing. In this study, high current metal inert gas(MIG) welding process was used to get one pass welding of thick plate aluminum alloy. Bead on plate(BOP) welding was performed to evaluate the effect of welding conditions on the height of bead and depth of penetration. The optimum welding conditions were derived to get one pass welding of the thickness of 14.5mm. The mechanical properties of the welded joint were evaluated. The cross-sectional macro test, tensile test, and bending test satisfied the class rule.

• Journal of the Korean Institute of Gas
• /
• v.2 no.3
• /
• pp.78-87
• /
• 1998

The mechanical properties, heat treatment and the history for the development of Ni-bearing ferritic steels for the application at low temperatures are reviewed. Ni-bearing ferritic steels are classified into $2-3\%$ Ni steels, $5.5\%$ Ni steel, $9\%$ Ni steel and $13\%$ Ni steel., of which $9\%$ Ni steels are most widely used for the large LNG storage tanks owing to their encellent fracture toughness up to $-196^{\circ}C$. The effect of retained austenite on the tensile properties and toughness was precisely discussed. As the size of LNG storage tank increases, thicker plates are needed. Thus, the recent efforts for the improvement of low temperature toughness and homogeneity are also introduced.

• Bulletin of the Society of Naval Architects of Korea
• /
• v.41 no.2
• /
• pp.94-99
• /
• 2004

전 세계적으로 천연가스의 수요가 급격하게 증가함에 따라 천연가스의 생산 및 공급이 활발하게 이루어지고 있고, 향후 10년 간 천연가스의 사용량이 현재의 2배 이상이 될 것이라는 추측도 나오고 있다. 이에 따라 천연가스 생산지에서는 천연가스 액화 플랜트(Liquefaction Plant)와 저장 탱크(LNG Storage Tank), 수입하는 곳에서는 재기화 플랜트(Regasification Plant)와 저장 탱크, 그리고 LNG를 운송할 LNG 운반선의 신조프로젝트가 활발하게 진행되고 있다. 미국의 경우 911테러와 NIMBY 사고의 확대로 인하여 LNG 수입기지의 육상건설을 주민들의 반대하자 해상에 건조하려는 경향을 보이고 있으며, 이에 따라 여러 가지 형태의 LNG Offshore 터미널이 설계되고 있다. 향후 LNG의 급격한 수입이 예상되는 나라로는 미국, 중국, 인도 등이 있으며 수출국으로는 카타르가 급격하게 부상하고 있다. (중략)

• Journal of the Earthquake Engineering Society of Korea
• /
• v.28 no.1
• /
• pp.21-32
• /
• 2024

This study performed the seismic response analysis of an LNG storage tank supported by a disconnected piled raft foundation (DPRF) with a load transfer platform (LTP). For this purpose, a precise analytical model with simultaneous consideration of Fluid-Structure Interaction (FSI) and Soil-Structure Interaction (SSI) was used. The effect of the LTP characteristics (thickness, stiffness) of the DPRF system on the seismic response of the superstructure (inner and outer tanks) and piles was analyzed. The analytical results were compared with the response of the piled raft foundation (PRF) system. The following conclusions can be drawn from the numerical results: (1) The DPRF system has a smaller bending moment and axial force at the head of the pile than the PRF system, even if the thickness and stiffness of the LTP change; (2) The DPRF system has a slight stiffness of the LTP and the superstructure member force can increase with increasing thickness. This is because as the stiffness of the LTP decreases and the thickness increases, the natural frequency of the LTP becomes closer to the natural frequency of the superstructure, which may affect the response of the superstructure. Therefore, when applying the DPRF system, it is recommended that the sensitivity analysis of the seismic response to the thickness and stiffness of the LTP must be performed.

• Journal of the Korean Society of Safety
• /
• v.31 no.4
• /
• pp.9-14
• /
• 2016

STS304L of membrane structure has been used for a LNG storage tank and has exposed long time under the cryogenic temperature. The purposes of this study are to evaluate the mechanical properties of base and used materials for STS304L of membrane. The tensile and high cycle fatigue tests were investigated for STS304L of membrane used over 20 years at room temperature and $-162^{\circ}C$. In addition, the test of base STS304L was performed in order to compare with used material properties. The chemical composition and phase change were investigated from EDS and XRD. From results of tensile test, yield and ultimate tensile strengths of used STS304L are smaller than those of base STS304L. S-N curves were obtained from fatigue tests at both temperatures. Also, P-S-N curves were presented with statistical method recommend by JSME-S002. Fractography was conducted for analysis of fracture mechanisms.