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The need to understand the associated risks of pressurized vessels and their consequences onboard ship is imperative. imperative. The handling and storage of Liquefied Natural Gas (LNG) mostly result in catastrophic accident with associated consequences. To quantify these consequences in terms of death and degree of burn depends on the tank structures and pressure control mechanism onboard LNG carriers in a harbor. harbor. In this research, the result of the potential risks and damage consequences of the LNG fire accident in terms of the degree of burns and fatality is presented. presented. The probability of death, first and second degree of burn injuries are assessed using consequence modelling technique, technique, while the pool fire was modelled using the BoilingLiquidExpanding Vapour Explosion (BLEVE) approach. approach. The result shows that at 30 meters from the flame radius,the probabilities for first-degree burn, second-degree burn, and death decrease, respectively. A sensitivity analysis revealed that at the initial heat flux and closer distance of 5m to 10m from the flame radius at the point of the accident, accident, the death rate, first degree, and second-degree burns increase significantly. significantly. Therefore, installing a safety system and best practices that will mitigate these risks to as low as reasonably possible should be incorporated into the system design.

The selection of the suitable propulsion system for LNG carrier highly affects the ship capital and life cycle costs. The current paper compares between the available propulsion systems for LNG carriers from environmental and economic points of view operated with heavy fuel oil (HFO) and marine gas oil (MGO). In addition, the cost-effectiveness for emission reduction due to using dual fuel propulsion options using natural gas fuel (NG) is calculated. As a case study, large conventional LNG carrier class has been investigated. The results show that steam turbine (ST), Ultra-ST, dual fuel diesel engine (DFDE), and combined gas and steam (COGAS) propulsion options can comply with NOx and SOx emissions regulations set by IMO using dual fuel mode with NG percentages of 87.5%, 82%, 98.5% and 94%, respectively. DFDE operated with pilot HFO and NG is the most economic propulsion option. It reduces the dual fuel costs by 1.37 MUS$/trip compared with HFO cost. The annual cost-effectiveness for the most economic and emission compliance propulsion option is 6.07 $/kg, 6.39 $/kg, and 0.55 $/kg for reducing NOx, SOx, and CO2 emissions, respectively [ABSTRACT FROM AUTHOR]

The importance of liquefied natural gas (LNG) vessels and the technology that enables their operations is steadily growing. Hence, in addition to professional interest, the general public also displays a considerably large interest in this issue. Today LNG carriers belong to the category of the most technologically developed vessels and therefore managing these vessels requires not only the general knowledge but also the specific knowledge relating to their cargo handling systems. To ensure the safe and economical transport of LNG by sea and to minimize the risk of fire or explosion it is necessary to understand the properties of LNG and nitrogen, an inert gas used in all phases of the carriage and transfer of liquefied gas. The subject of this research is the overall process of nitrogen management in daily operations on board LNG carriers. The aim of the research is to explain, evaluate and define the various applications of nitrogen systems on LNG carriers. [ABSTRACT FROM AUTHOR]

LNG subcooling system is a conventional system to keep the pressure of an LNG storage tank for LNG carriers, but has a weak point of the low efficiency resulting in a new BOG reliquefaction system. This study suggests a new LNG subcooling system combined with mixed refrigerant cycle (MR-SLNG), which can increase efficiency significantly. The results show the coefficient of performance (COP) of the system becomes 2.5 times higher than that of the conventional LNG subcooling system based on a reverse Brayton cycle (RBC-SLNG). Additionally, MR-SLNG can be a compact system because the volumetric flowrate of the refrigerant compressor decreased to 8.9%, which brings additional benefits to the ship design. • A new LNG subcooling combined with mixed refrigerant cycle (MR-SLNG) is proposed. • Effect of flash gas generation on BOG reliquefaction system is also investigated. • Flash gas generation should be considered because it reduces COP by 2.5–46%. • COP of MR-SLNG increases by 120% compared to a conventional subcooling cycle. • The suggested MR-SLNG cycle can reduce the size of refrigerant compressors by 9%. [ABSTRACT FROM AUTHOR]

Problems resulting from gas emissions lead to increase the concern about safety and health issues with the demand to reduce the emissions from marine shipping. Marine power plants are considered as one of the greatest contributors in the pollutants around the world. Waste heat recovery systems when implemented with ship propulsion system can reduce emissions, fuel consumption and improve the overall efficiency of power generation and utilization. The present article describes the waste heat recovery technology and the potential for ship operators to lower the fuel costs, exhaust emissions, and the effect on the EEDI of the ship. The main research target is to improve the propulsion machinery efficiency of liquefied natural gas carrier using WHRS. The proposed system leads to meet the requirements and regulations set by the IMO for TIER III.

The increase of marine shipping industry leads to search for the use of clean source of energy such as natural gas to use in the primary propulsion systems. The LNG propulsion systems have been applied for years in different disciplines. Recently, the same are reused with the modern technologies and improvement. Over the years the steam turbine propulsion proved to be the dominant type of propulsion system used in Natural Gas Carriers, even though this system has been for years there was always the need to search for further improvements with the main goal to meet the mandatory requirements of the International Marine Organization. The current trend in the market is the implementation of a waste heat recovery system with dual fuel diesel engines with two main goals, first is to reduce the emission and second is to increase the overall efficiency. The current study is concerned with seeking further improvements that coincide with the market trend, thus a proposed system of a dual fuel diesel engine with a waste heat recovery system implemented is studied to investigate the possibility of those improvements and compared with the available propulsion systems.

LNG chain value consists of gas exploration, gas liquefaction, transportation, Re-gasification and finally gas distribution to the end user network. Transportation part of this chain normally consists of 25 to 30% of the total vale and is the most lucrative part of it. As proved Iranian gas reserves is about 29 trillions cubic meter and nearly half of it is South PARS gas field shared between Iran and Qatar ,there is an increasing concern on entering into gas export market in near future. This enthusiasm enquires a thorough financial study on economical feasibility study on this industry. In this study by emphasizing on key parameters of LNG shipping industry like, technical vessel specification distance between exporting and importing terminals, cost of LNG carriers , boil of ratio of vessels, oil and gas future price prediction vessels heeling portions and most importantly the difference between vessel purchase and hiring daily rate of vessels. We are to model this industry economically and by doing an economical sensitivity analysis on the model some economical indexes are extracted which are of most benefit for countries decision makers. Two scenarios of purchasing and renting vessel have been investigated and it is shown than in different financial condition and oil and gas market there are at least minimum internal rate of return of 4 to 18% and at last these finding have been demonstrated in a 3D diagram showing net in come oil price (as an important parameters) and rent daily rate of vessels to show the profitability of this industry to the reader.

The transport of liquefied natural gas (LNG) has significant impact on traffic capacity of waterways, especially the approach channels shared by LNG carriers and other types of ships (general cargo ships, container ships, etc.). Few studies take the behavioral characteristics of LNG carriers and their impacts into consideration. In this paper, we propose a framework for capacity analysis of shared approach channels based on the spatial–temporal consumption method. It consists of three modules: (1) the tide module predicts the tidal height and tidal time for identifying the time windows for LNG carriers; (2) the spatial–temporal consumption module is introduced to calculate the capacity of approach channels; (3) the LNG carrier navigation module is for analyzing the characteristics of LNG carriers and the impact on the capacity of approach channels. A spatial–temporal indexed chart is designed to visualize the utilization of the spatial–temporal resources. A case study on the approach channel of Yueqing Bay near the east coast of China is conducted to verify the effectiveness of the framework. The utilization rates of the approach channel and the impact of LNG carriers are presented using our method. The results of the case study indicate that the proposed traffic capacity analyzing framework can provide support for making traffic management strategies.

Ever growing energy industry requires larger quantities of LNG to be transported by bigger ships between terminals. Every day, new kind of large vessels created by new technologies, and these are used to trade around the globe. This is the dynamic change in shipping industry. But on the other hand these new vessels need to safely berth to existing terminals which we may accept as more static part of the trade. Thus this study born by the request of Ege Gaz Aliaga LNG Terminal management to determine if it is safe to berth to the terminal by a new breed of large LNG carrier type named as Q-Flex and Q-Max. Transas Bridge Simulator NTPRO 5000 series was used in this study for extensive experiments which had been simulated by the use of hook function. During the study, every force applied to mooring hooks and dolphins by the ship lines were divided into 3 dimensions and then measured by simulation experiments. With analysis of the data, required hook and dolphins strengths were determined for the safe mooring arrangements. Upon the completion of the study Ege Gaz Aliaga LNG Terminal became the first safe berth for Q-Flex type vessels in the Mediterranean and the Black Sea. And finally all experiments were confirmed with real life experience when the first Q-Flex type LNG carrier berthed to the Ege Gaz Aliaga LNG Terminal.

An ejector-enhanced Liquefied Natural Gas (LNG) boil-off gas (BOG) re-liquefaction system is proposed to improve the energy efficiency of the existing system. In the new system, two ejectors are respectively used to reduce the energy loss in the expansion of the pressurized BOG and inject a part of fuel BOG into the compression system, and a recuperator is employed to recover the cold energy of the BOG exited from LNG tank. The performance improvement of the proposed system is analysed on the basis of the simulation in Aspen HYSYS. In the case of the re-liquefaction capacity of 4557.6 kg/h, the coefficient of performance (COP) and exergy efficiency can be increased by 28%, and the specific energy consumption (SEC) reduced from 0.756 to 0.59 kW h/kg(BOG) compared to the conventional BOG re-liquefaction system. Correspondingly, the power consumption of 754.1 kW is saved. This means that applying ejectors can effectively improve the energy efficiency of the existing BOG re-liquefaction system for LNG carriers. [ABSTRACT FROM AUTHOR]

Natural gas is relatively cheap, environmentally friendlyand energetically efficient fossil fuel that is gaining in attractivenessdaily as it can be used in many sectors. As not all consumerscan be reached by pipelines the technique of transp01tingnatural gas in the liquefied form has been developed at the beginningof 20th century but it was only in 1959 that the firstoverseas transport of liquefied natural gas ( LN G) occurred. Inthe fifty years of operation LNG shipping has shown immaculatesafety records. LNG tankers can be described only in superlatives;they are without any doubt the most sophisticated and·expensive ships that sail around the globe, they demand specialattention when navigating to or out of harbours and need to bemanned with the most educated and experienced crew. LNGmarket is expanding and changing; demand is surpassing theproductivity, new importing and exporting countries appear,LNG fleet is growing in capacity and number at high pace, exploitationcontracts for the ships are being modified giving theopportunity for new companies to enter( . .. ). The paper givesan overview on liquefied natural gas market and the historic developmentof LNG shipping. It focuses on the recent boom inLNG shipping and emphasises questions concerning the safety,crewing and exploitation of the LNG tankers in the future.

Problems resulting from gas emissions lead to increase the concern about safety and health issues with the demand to reduce the emissions from marine shipping. Marine power plants are considered as one of the greatest contributors in the pollutants around the world. Waste heat recovery systems when implemented with ship propulsion system can reduce emissions, fuel consumption and improve the overall efficiency of power generation and utilization. The present article describes the waste heat recovery technology and the potential for ship operators to lower the fuel costs, exhaust emissions, and the effect on the EEDI of the ship. The main research target is to improve the propulsion machinery efficiency of liquefied natural gas carrier using WHRS. The proposed system leads to meet the requirements and regulations set by the IMO for TIER III. [ABSTRACT FROM AUTHOR]

There is a high demand for natural gas in the Asia-Pacific region. Most of this gas is exported from the Middle East, Australia, Indonesia, and Malaysia. There is interest in the Asia-Pacific to diversify its import portfolio. From a Canadian perspective, there are abundant resources of natural gas in Western Canada, and countries in the Asia-Pacific are potential customers. This paper develops the cost of shipping a unit of natural gas (in liquefied form) from proposed liquefaction facilities in Western Canada to liquefied natural gas (LNG) re-gasification terminals in Asia-Pacific countries (Japan, China, and India). Fundamental engineering principles-based models were developed to estimate costs. A comparative analysis of delivery costs to Japan, China, and India is presented. To account for various propulsion systems available for LNG carriers, five scenarios were developed. Calm water resistance for the two different categories of LNG carriers was estimated. These estimates were used to determine the required propulsion power needed for an LNG carrier at a given speed and to select the appropriate main engine. The results of this study show that shipping costs to Japan range from 51–95 U.S. cents/GJ depending on the type of propulsion system selected and for an average transport distance of 7793 km. The shipping costs to China and India range from 59–113 U.S. cents/GJ and 98–197 U.S. cents/GJ for an average transport distance of 9475 km and 17,035 km, respectively. The results show that a propulsion system burning only natural gas as primary fuel is the most economical scenario, while a propulsion system based on pure marine diesel oil is the least economical. In addition to a sensitivity analysis, a risk analysis was conducted to identify the range of shipping costs in each scenario with their occurrence probability measure. [ABSTRACT FROM AUTHOR]

Structural safety is one of the most important issues associated with liquefied natural gas (LNG) storage systems, such as LNG carriers, LNG Floating Production Storage Offloading (FPSO), and Floating Storage Re gasification Unit (FSRU). One of the most common materials for the LNG storage systems has been 9% nickel steel over the last 50 years as it has excellent mechanical properties under cryogenic temperature. Recently, there have been efforts for lowering the nickel content due to the increased nickel price as well as the high price of nickel based welding consumables. In this respect, 7% nickel steels are recently developed for reducing the associated costs mainly for cryogenic applications. The newly developed 7% nickel steels are known to have improved toughness comparable to that of 9% nickel steels by thermomechanical control process (TMCP) and microalloying technology. The main objective of this study is to evaluate the fatigue performance of 7% nickel steels with a special attention to type B LNG carrier applications. Cyclic fatigue and fatigue crack growth rate (FCGR) tests for 7% nickel steels were conducted at room and cryogenic temperatures. Fatigue tests were carried out with three different types of specimens such as base metal, butt weld, and fillet weld to characterize the fatigue properties at various locations. In addition, FCGR tests were carried out using compact tension (C(T)) specimens. The difference of FCGR characteristics among base, weld, and heat affected zone (HAZ) is investigated. The fatigue and FCGR test results of 7% nickel steels are evaluated and compared with reference data of 9% nickel steel. Based on this study, it is observed that the 7% nickel steel exhibits similar fatigue performance in comparison with that of 9% nickel steel. [ABSTRACT FROM AUTHOR]

This paper presents analyses future powering options for LNG carriers when considering the Energy Efficiency Design Index (EEDI). The IMO has recently approved amendments to MARPOL Annex 6 to extend the application of the EEDI to include LNG Carriers (LNGCs). This paper investigates the impacts of this upcoming EEDI regulation, due to be enforced from September 2015, will have on the design of future LNGCs. The study found that the current EEDI reference baseline is insufficient to stimulate improvements in the design of future LNGCs because the current Dual Fuel Diesel Electric (DFDE) propulsion proposed to be installed on majority of future LNGCs orders already achieves EEDI values that are compliant with the EEDI baseline. Analysis of EEDI values for LNGCs employing the new two-stroke gas injection diesel propulsion system also displayed similar results. However when considering unburnt methane emissions of the DFDE it was seen that the GHG emission index value could potentially rise by up to 115% meaning the EEDI is limited in its value to reduce global warming. This paper also proposes and analyses amendments to the EEDI baseline values for LNGCs as well as suggesting methods to include methane slip emissions into the current EEDI calculations. [ABSTRACT FROM AUTHOR]

Electric propulsion has emerged as one of the most efficient propulsion arrangements for several vessel types over the last decades. Even though examples can be found in the history at the end of 19th century, and further into the 20th century, the modern use of electric propulsion started in the 1980s along with the development of semiconductor switching devices to be used in high power drives (dc drives and later ac-to-ac drives). This development opened up for full rpm control of propellers and thrusters, and thereby enabling a simplification of the mechanical structure. However, the main reason for using electric propulsion in commercial ship applications is the potential for fuel savings compared to equivalent mechanical alternatives, except for icebreakers where the performance of an electric powered propeller is superior to a combustion engine powered propeller. The fuel saving potential lies within the fact that the applicable vessels have a highly varying operation profile and are seldom run at full power. This favors the power plant principle in which electric power can be produced at any time with optimum running of prime movers, e.g., diesel engines, by turning on and off units depending on the power demand for propulsion and other vessel loads. Icebreakers were among the first vessels to take advantage of this technology later followed by cruise vessel, and the offshore drilling vessels operating with dynamic positioning (DP). The converter technology was rapidly developing and soon the dc drives were replaced with ac drives. In the same period electric propulsion emerged as basic standard for large cruise liners, and DP operated drilling vessels, but also found its way into other segments as shuttle tankers, ferries, and other special vessels. At the same time podded propulsion were introduced, where the electric motor was mounted directly on the propeller shaft in a submerged 360 ^\circ steerable pod, adding better efficiency, improved maneuvering, and reduced installation space/cost to the benefits of electric propulsion. The future trends are now focusing on further optimization of efficiency by allowing multiple energy sources, independent operation of individual power producers, and energy storage for various applications, such as power back up, peak shaving, or emission free operation (short voyages). [ABSTRACT FROM PUBLISHER]

This paper presents an approach to analyze the fuzzy reliability of dual-fuel steam turbine mechanical propulsion conventional (DFSMC) system of LNG carriers utilizing best available data collected from various sources which may have some sort of uncertainties. Quantification of uncertainties present in collected data has been done through data fuzzification using triangular fuzzy numbers with known spreads as suggested by system experts. In these conditions, if available techniques such as FLT (fuzzy lambda-tau) and GABLT (genetic algorithms based lambda-tau) are applied for DFSMC system reliability assessment using quantified data then the computed reliability indices have wide ranges of prediction due to the complexity of the system. Using these results, decision-maker may suggest some impressive corrections which may improve the system performance. However, it may also be possible that after incorporating suggested corrections, system performance may not improve upto the desired level because suggestions are inappropriate due to the wide ranges of prediction. In order to reduce the prediction ranges of computed fuzzy reliability indices, and to select suitable and effective strategic decision making, this study applies the weakest t-norm ( T ω ) based approximate arithmetic operations for evaluating some very important fuzzy reliability indices of the system. Sensitivity analysis has also been conducted in an ideal condition for analysing the effects of various reliability parameters on system performance. To rank the critical components of the system, Tanaka et al. (1983) approach has been extended for repairable systems and then utilized for this purpose. The analysis can help maintenance personnel to understand and plan suitable maintenance strategy to improve the overall performance of the system. Based on results some influential suggestions are given for improving system performance. [ABSTRACT FROM AUTHOR]

Natural gas, being the cleanest burning fossil fuel, will play a key role in the future. Liquefying natural gas lets moving it to regions where pipeline transport is not possible, allowing end-use markets access to natural gas. LNG is more energy dense than gaseous natural gas, so there using fields are still increasing in end-use applications, e.g. different types of transportation (heavy duty vehicles, marine or rail applications). Global LNG demand is expected to grow, mostly because of new economic markets from Asia and Middle East. [ABSTRACT FROM AUTHOR]

The objective of this study is to investigate the typical failure mode and to obtain the stress range versus number of cycles to failure (S-N) data of MARK-III type liquefied natural gas (LNG) insulation system under the fatigue loading at actual cryogenic environment. A systematic experimental research is carried out for the assessment of the fatigue strength of MARK-III insulation system at cryogenic temperature. Three different types of test specimens are tested for the evaluation of fatigue performance of MARK-III insulation system. Test specimens are determined considering the fatigue vulnerable locations such as mastic area, slit area, and top bridge pad area inside the actual LNG cargo tanks. All test specimens are fabricated as close as possible to the actual yard practice. A series of fatigue test results is represented as S-N curves. Cyclic fatigue loadings were carefully considered similar to the actual sloshing loads. The effect of sloshing impacts is considered by selecting the stress ratio (R=-10). The load levels have been determined based on the ultimate strength of reinforced polyurethane foam as 12.2 bars. Different cryogenic temperatures are employed according to the test locations in consideration of temperature gradient within the insulation system. All test results including fatigue life, as well as failure locations of MARK-III insulation system at cryogenic temperatures, are reported and compared with those at room temperature. Consistent S-N curves of MARK-III insulation system at both room and cryogenic temperatures are obtained and compared. The slopes of S-N curves from both fatigue test results are observed to be almost identical, and the fatigue strengths are found to exhibit similar trend. The results from this research can be used for the fatigue assessment of the LNGC insulation system, as well as a design guideline of LNG CCS at cryogenic temperature. [ABSTRACT FROM AUTHOR]

Abstract: Numerous real-world problems related to ship design can be solved by various alternatives. However, the scantling design has conflicting objectives such as minimum production cost, minimum weight and maximum moment of inertia (stiffness). Therefore a multi-purpose solution had to be settled in order to meet all these requirements at once. Ship design is a complex endeavour requiring successful coordination of many different disciplines, both technical and non-technical. Basic design is the least defined stage of the ship design process and seeks to define the optimal amidships section structure. For that purpose, recent improvements have been made to a numerical tool in order to optimise the scantling of ship sections by considering production cost, weight and moment of inertia in the optimisation objective function. A multi-criteria optimisation of a LNG carrier is conducted in this paper to illustrate the analysis process. Pareto frontiers are obtained and results have been validated by the Bureau Veritas rules. The methodology presented in this paper has demonstrated its effectiveness in optimising scantling of ships at a very early design stage thanks to a management of critical problems usually studied at a later stage of the design. [Copyright &y& Elsevier]

LNG holds great promise as a transportation fuel making significant reductions in emissions and green house gases. The road to increased use of LNG as a heavy transportation fuel in the U.S. is the development of a coherent LNG supply infrastructure. The existing LNG import terminal infrastructure can be leveraged to implement a safe and reliable fuel supply infrastructure. This paper will discuss the transshipment of LNG, by an AT/B LNG carrier, from existing U.S. LNG import terminals, in a hub and spoke arrangement. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a generic, high-level risk assessment of the global operation of ocean-going liquefied natural gas (LNG) carriers. The analysis collects and combines information from several sources such as an initial hazid, a thorough review of historic LNG accidents, review of previous studies, published damage statistics and expert judgement, and develops modular risk models for critical accident scenarios. In accordance with these risk models, available information from different sources has been structured in the form of event trees for different generic accident categories. In this way, high-risk areas pertaining to LNG shipping operations have been identified. The major contributions to the risk associated with LNG shipping are found to stem from five generic accident categories, i.e. collision, grounding, contact, fire and explosion, and events occurring while loading or unloading LNG at the terminal. Of these, collision risk was found to be the highest. According to the risk analysis presented in this paper, both the individual and the societal risk level associated with LNG carrier operations lie within the As Low As Reasonable Practicable (ALARP) area, meaning that further risk reduction should be required only if available cost-effective risk control options could be identified. This paper also includes a critical review of the various components of the risk models and hence identifies areas of improvements and suggests topics for further research. [Copyright &y& Elsevier]

The transport of liquefied natural gas (LNG) has significant impact on traffic capacity of waterways, especially the approach channels shared by LNG carriers and other types of ships (general cargo ships, container ships, etc.). Few studies take the behavioral characteristics of LNG carriers and their impacts into consideration. In this paper, we propose a framework for capacity analysis of shared approach channels based on the spatial–temporal consumption method. It consists of three modules: (1) the tide module predicts the tidal height and tidal time for identifying the time windows for LNG carriers; (2) the spatial–temporal consumption module is introduced to calculate the capacity of approach channels; (3) the LNG carrier navigation module is for analyzing the characteristics of LNG carriers and the impact on the capacity of approach channels. A spatial–temporal indexed chart is designed to visualize the utilization of the spatial–temporal resources. A case study on the approach channel of Yueqing Bay near the east coast of China is conducted to verify the effectiveness of the framework. The utilization rates of the approach channel and the impact of LNG carriers are presented using our method. The results of the case study indicate that the proposed traffic capacity analyzing framework can provide support for making traffic management strategies. [ABSTRACT FROM AUTHOR]

• This study examined the effects of cold rolling ratio and cryogenic temperatures on the mechanical properties of a 1.5 mm SUS304L sheet. • Moreover, to identify the effect of cryogenic temperatures, very high cycle fatigue (VHCF) characteristics were obtained at −162 °C and −196 °C, using the ultrasonic fatigue tester. • The increase in the fatigue limit caused by to the cold rolling and cryogenic temperatures in the results of the UFT is similar to the tendency of increased tensile strength and dynamic elastic modulus. This study examined the effects of cold rolling ratio and cryogenic temperatures on the mechanical properties of a 1.5 mm SUS304L sheet, the original material used in membrane-type liquefied natural gas (LNG) storage tanks. The original sheet was cold rolled to reduce its thickness in order to examine the effect of cold rolling ratio. And to identify the effect of cryogenic temperatures, very high cycle fatigue (VHCF) characteristics were obtained at −162 °C, using the ultrasonic fatigue tester. The fatigue limit of a 1.5 mm specimen, measured at −162 °C in the ultrasonic fatigue test (UFT) was 252 MPa, while that of 1.3 mm and 1.1 mm cold rolled specimens was 503 MPa and 597 MPa, up by about 99.6% and 137% respectively. The fatigue limit of 1.3 mm and 1.1 mm cold rolled specimens measured at −196 °C was 550 MPa and 690 MPa, up by about 88.4% and 136.3% respectively. As such, the fatigue strength of the cold rolled specimen in the UFT tend to increase in a nearly linear manner, compared to that of the original material, as the cold rolling ratio and the effect of cryogenic temperatures. [ABSTRACT FROM AUTHOR]