bluuebunny/crossref_metadata_2025 huggingface dataset:
Integrated pressure control strategies for sustainable management of water distribution networks
Authors: Berardi Luigi , Laucelli Daniele , Simone Antonietta , Perrone Gianluca C. , Giustolisi Orazio
Published: February 2019

Pressure control in urban Water Distribution Networks (WDNs) allows to reduce water losses, delays asset deterioration and makes effective replacement works. This contribution presents an integrated approach to control pressure for leakage reduction that combines a recent strategy for optimal design of district metered areas (DMAs) with optimal setting of pressure reduction valves. DMA design strategy encompasses the possibility of reconfiguring water flows by closing some gate valves at district boundaries, while the optimal setting of PRVs driven by local or remote real time controls improves leakage reduction and reliability of final solution. The integrated approach is implemented into the WDNetXL platform for advanced WDN analysis, planning and management and is demonstrated on a real urban WDN in Southern Italy. As such, this work proposes an innovative methodology while demonstrating its transfer to water utilities and practitioners to support decisions in real-world complex scenarios.
Vibrations of water hydraulic systems – an experimental approach
Authors: Dragomirescu Andrei , Safta Carmen-Anca , Orăşanu Nicolae , Magheţi Ioan , Mândrea Lucian
Published: February 2019

This paper presents an experimental study of the vibrations induced both by cavitating and by non-cavitating flow in a hydraulic installation that comprises the main elements of a water hydraulic system. The cavitation was triggered by progressively closing a butterfly valve. The vibrations were measured on the pump, on the bearings housing, on the pump drive motor, and at nine measurement points located upstream and downstream of the main elements of the installation. The measurements were carried out at different flow rates obtained at different openings of the butterfly valve. The results suggest that the phenomena that take place inside the pump and inside the bearings cause vibrations having frequencies of up to 10 kHz. The results also indicate that the cavitation that occurs at the butterfly valve causes vibrations of high frequency, above 3 kHz, that have a distinct peak at about 18 kHz. These results could be useful in establishing proper maintenance plans for hydraulic installations.
Hydraulic model for water management along Dâmboviţa River through Bucharest City, Romania
Authors: Gogoaşe Nistoran Daniela Elena , Ionescu Cristina Sorana , Georgescu Mihail , David Doruleţ Stefan
Published: February 2019

The main objective of the paper is to simulate the steady state flow conditions along the regulated Damboviţa River in Bucharest City. The canal has 11 reaches in series separated by control structures with gated weirs (barrages). The simulations are performed using the 1D HEC-RAS software for flows between 3 and 45 m3/s, in order to find the optimal opening of each set of gates, so that water levels along reaches are kept at the target Normal Pool Levels (NPL) elevation. For the determined operating situations optimized gate openings and gates' rating curves are drawn. The computed water surface profiles for the maximum flow allow for checking if the banks are flooded, whereas velocity values for the minimum, ecological flow of 3 m3/s highlight the reaches over which the biota could be affected during summer drought periods. This model could assist the Water Management Authority's technical staff to better operate the gates in an integrated manner. Since currently gate operations are individually performed at each control structure, such a model would be a primary step in designing and implementing an automatic controlling system for the entire Damboviţa canal in Bucharest City.
Removal of escherichia coli using waste stabilization pond: A simulation in climatic conditions of Libya
Authors: Faskol Adel , Racoviţeanu Gabriel
Published: February 2019

The most important determinant when recycling of wastewater for agriculture is that related to public health. This paper investigates the removal of Escherichia Coli/coliform in the waste stabilization pond as simulation as assessing of mitigating health risk. A case study in climatic conditions of Libya. As a result of a computer program based waste stabilization pond design based on parameter uncertainty and 10,000-trial Monte Carlo simulations, were developed for a series of anaerobic, facultative and maturation ponds to produce on a 95%-ile value <1000 E. Coli per 100 ml. While a number of influent of E. Coli bacteria was (156.732×106E. Coli /100ml). Where it decreased was a number of the effluent (10 E. Coli /100ml). Where the efficiency of removal E. Coli bacteria was (99.999 %). And the overall hydraulic retention time it took 89.548 days in the anaerobic pond, facultative pond, first maturation pond and twelve of the subsequent maturation ponds. To satisfy practice 2006 WHO guidelines for the safe use of wastewater in agriculture.
Mathematical modelling and interpretation of results for siltation phenomena of rivers in the vicinity of reservoirs
Authors: Popescu Cătălin , Lungu Laurenţiu , Zaharia Valentin , Sârghiuţă Radu
Published: February 2019

Worldwide the processes of erosion, transport and sedimentation have a significant social, economic and environmental impact. In the past decade the most important external factor that has significantly increased the erosion and sediment process is the human factor throughout its daily activities. The changes of land cover and use, the intensive deforestation, urbanization and infrastructure development, sand extraction from river beds alter the natural watercourse and thus leading to erosion, sediment transportation and finally to the silting of rivers and reservoirs. The process of erosion and sedimentation occurs, among other areas, in the hydro-technical constructions with significant effects. In the next 30 years it’s expected to lose more than 50% of the storage capacity of the reservoirs in the world due to the silting phenomenon. The control and monitor of the sediment dynamics represents a critical component in the sustainable management of water resources. Also the understanding of the involved phenomena is essential in order to develop solution for reducing the sediment and erosion that occur and adopt measures to extend the life of the reservoirs. This paper taps the solution of mathematical modelling using dedicated software in order to establish the morphological changes that occur in Ogrezeni-Crivina reservoir, located on the river Arges.
Impact of coastal protection systems on marine ecosystems
Authors: Anton Iulia Alina , Panaitescu Mariana , Panaitescu Fanel-Viorel , Ghiţă Simona
Published: February 2019

Various solutions, which consist of numerous techniques, technologies and planning measures, are testing for reduction shoreline erosion, precisely for protection shore against waves attack. These methods may affect the site's geology and geomorphology, involving changes of the habitats in the site. Coastal defense projects and ideas must take into account the structure and functions of protected natural areas and their conservation objectives in order to avoid threatening the species and/or habitats on the site. The ecological impacts expected from coast protection structures on short-term are mostly negative, may disturbance the birds from their habitat, and destruct the marine coastal habitats with their own flora and fauna. In this study, we are indicating the effects of coastal protection measures on the ecosystem. Therefore, we present a part of methods applied or which will be apply on the Romanian shoreline and the effects that have an impact on the species and/or habitats on the site. The methods referred to “hard” methods so to harder the shore with fixed structure (bulkhead, seawall, revetment, breakwaters, sills or groins) or “soft” methods like beach nourishment that is not a sustainable method in time. The protection structures like breakwaters and groins trap or add sand and will change the beach geometry this means that can introduce new artificial material, which is extensively and rapidly colonized by algae and marine animals. In the cases of beach nourishment, under water sand nourishment and mudflat recharge, there are impacts both at the borrow site (the sediment source) and the target site. In the zone of extraction of borrow, sediments appear a damage and mortality to the benthos. Finally, it can conclude that some of the effects are beneficial for socio-economic aspect, but it is important also, the environment, which can bring bad consequences for earth landscape and make the ecosystem, be unbalanced.
Mechanical and thermal characterization of a beet pulp-starch composite for building applications
Authors: Karpaky Hamzé , Maalouf Chadi , Bliard Christophe , Gacoin Alexandre , Lachi Mohammed , Polidori Guillaume
Published: February 2019

This work shows the making of a new bio-based material for building insulation from sugar beet pulp and potato starch. The material is both lightweight and ecofriendly. The influence of starch/ sugar beet pulp ratio (S/BP) is studied. Four binder mass dosages are considered, 10, 20, 30 and 40% (relative to the beet pulp). Samples are characterized in terms of absolute and bulk density, compressive and flexural strength, as well as thermal properties (thermal conductivity and thermal inertia). The compressive strength increases linearly with the S/BP mass ratio to reach 0.52 MPa and the compressive strain is 30%. The thermal conductivity is to around 0.070 W/m. K. The results obtained shows that increasing starch amount tends to decrease composite porosity but increases thermal conductivity and mechanical properties. Depending on the starch content, beet pulp composites have a good thermal and can be used as building materials.
Experimental research in mechanic's field of control for further innovation in the hydraulic and electronic operated injection system
Authors: Ferenţi Iosif , Opruţa Dan , Băldean Doru
Published: February 2019

In the present research paper is detailed an experimental work concerning Engine Control Unit (ECU) in order to trace predictive trend-lines regarding operational parameters such as ignition timing, fuel supply, injection duty, at more than ten engine speed regimes in the case of a powertrain for motor-sport competition, with distinct air pressures, injector status and spark advances. An experimental study of real values and trend-lines as well as actuator's output data was realized in order to point out electronic control unit's functional characteristics and to redefine the economic field with optimal combustion pressure, efficient mixture formation/burning and diminished emissions as a consequence of the proper measures. Air intake pressure influences the fundamental conditions for intake charge definition and for lambda level even prior to engine cycle beginning in the powertrain with port fuel injection (PFI). Lambda value expresses the operational quality in relation with the excess air intake compared to the minimal amount necessary for a complete combustion of fuel jet charge.
Soil-tool interaction of a simple tillage tool in sand
Authors: Fechete-Tutunaru Lucian V. , Gaspar Ferenc , Gyorgy Zoltan
Published: February 2019

This study was focused to experimentally evaluate the draft force on a simple tillage tool operating in different conditions in sand. The soil-tool interaction was evaluated in controlled laboratory conditions in a soil bin. A full multilevel factorial experiment was used with one response variable and four experimental factors. The selected design 3 tools × 3 tillage depth × 3 rake angle × 3 forward speed with two replications had a total of 243 runs. Influence of four independent variables including tillage depth (15, 20, 25 cm), rake angle (25, 35, 50 degrees), forward speed (0.67, 0.98, 1.39 m/s) and cutting-edge angle of the tool (30, 45 and 60 degrees) on draft force as the dependent variable was evaluated.
Problematic aspects of registering ecological land-use in the Real Estate Cadastre
Authors: Benduch Piotr , Pęska-Siwik Agnieszka , Hanus Paweł
Published: February 2019

Land-use as a part of the earth’s surface used in an unitary manner, constitutes as one of the objects of Real Estate Cadastre in Poland. This register gathers data concerning actual grounds status, buildings and premises. Cadastre is carried out in an informational system on the basis of Geodetic and Cartographic Law and its implementing act. The contents of mentioned legal regulations are very general in terms of capturing and revealing data on ecological land-use. The rules are also related to environmental protection law. It often makes its proper interpretation difficult. In this article, the study aimed to systematize information about recording ecological land-uses in Polish Real Estate Cadastre has been performed. Practical and legal solutions concerning determination of the ecological land-uses coverage have been presented. The authors evaluate an order of individual activities leading to ecological land-use disclosure in cadastral database. The consequences and constraints in enforcing the ownership to land property or its parts where ecological land-use was allocated are analyzed as well. The statistical data in the scope of number and surface area of ecological land-uses in individual provinces have also been demonstrated.
Possibility of the modelling of electricity production from hydropower
Authors: Operacz Agnieszka , Szeląg Bartosz , Grahl-Madsen Mads
Published: February 2019

In hydropower plants benefits depends on available flow. The paper presents a hybrid model for forecasting the operation of a hydropower plant, including the production of electricity. The possibility of mathematical modeling was chosen to show connections between observed in the past hydrological conditions (available flow) and energy deliver in the future. The available flow which is not enough for start turbines was forecasting by logistic regression model. The opposite situation when the flow starts turbine to produce energy, regression models (the support vector machines SVM, random forest RF, k nearest neighbour k-NN) were used. Results from hybrid model were compared with chosen data-mining methods. The possibility of forecasting of the length of periods when hydropower plant will be working could be very useful. It provides the prognosis of energy value which could be produced from hydropower plant. From the investors’ point of view the economic justification for the execution of the project based on the future energy producing could be a main criteria to realize or buy/sell hydropower plant. Also the secondary importance could be a possibility of planning review and maintenance work. Knowledge of power plant working periods could be a base for assessing a potential production from hydropower plant.
The implementation of spatial management as a factor supporting flood protection
Authors: Jasińska Elżbieta
Published: February 2019

This publication presents the issues related to cadastre and real estate management in flood protection. Cadastral data supported by other additional data is the basis for taking action in situations of natural hazards. A real estate cadastre is an important element in the implementation of a real estate acquisition plan. It allows for preliminary assessment of the negative impact of the project, change of the concept and, as a result, expropriation and compensation regulation. In parallel with the activities related to the acquisition of real estate, it is possible to regulate the legal status of other properties. In this publication, the analysis is based on the document entitled "Plan of obtaining real estate and resettlement for the Flood Protection Project in the Odra and Vistula basin, Component 3B: Protection against Sandomierz flood and Tarnobrzeg, Contract 3B.3, flood protection Tarnobrzeg - stage 1 (Wisła 1) ". This area is the research material of actions changing the forms of land management in order to increase the safety of areas exposed to floods. The effects of carrying out this project were an important part of the work, including restrictions in the use, loss of real estate. The implementation of a flood protection project may have a negative impact on the economic status of people living in the areas where the activities were planned. These may be restrictions on the use of real estate, in particular the loss of a part or the whole of the property as a result of expropriation. Ultimately, such actions may result in the resettlement of residents. As a part of the study, the compensation for particular entities was described in detail. The results of surveys confirming the lack of a negative impact on the economic situation of people affected by the project implementation were presented.
Influence of environmental factors on retention of extensive green roofs with different substrate composition
Authors: Baryła Anna , Karczmarczyk Agnieszka , Bus Agnieszka , Hewelke Edyta
Published: February 2019

Increasing recognition is being given to the adaption of green roofs in urban areas to enhance the local ecosystem. Green roofs may bring several benefits to urban areas including flood mitigation Analysis of environmental factors affecting the outflow of green roofs is the subject of many studies. The work assessed how environmental factors moisture of structural layers and antecedent dry weather period influence the retention on two types of green roof substrates. The monitoring of environmental factors and amount of runoff was carried out on two models of green roofs covered by extensive vegetation (mosssedum-herbs) with substrates of an organic-mineral and mineral composition for 8 months. A statistical regression approach identified potential antecedent meteorological factors and moisture indicators of extensive green-roof retention. Continuous field monitoring data revealed the combined effects of rainfall depth and antecedent dry weather period to explain the measured stormwater retention under a moderate climate conditions regime. It is important to incorporate site-specific planning and assessment prior to green infrastructure design.
Efficiency of Pollutant Removal from Surface Water in a Conventional Water Treatment System
Authors: Jachimowski Artur
Published: February 2019

The article contains an assessment of efficiency of removal of impurities from surface water using the technology employed by “Raba” plant of the Municipal Water and Sewerage Company in Cracow (MPWiK). Research conducted by the laboratory staff shows that the functioning process system for water treatment makes it possible to obtain water with parameters corresponding to the currently applicable regulations on the quality of treated water at the outlet of the plant. Selected microbiological indicators during the treatment process and physicochemical parameters in raw and potable water underwent statistical analysis. In the first case, only Clostridium perfringens bacteria and coliform bacteria were analysed. The other bacteriological parameters in the water production process gave a result of 0 cfu/100 ml. In the second case, the average rates of removal of impurities were calculated in order to check the efficiency of the treatment process. In the examined water, the highest efficiency of removal of impurities was observed with regard to the following indicators: nitrates (III), turbidity, colour, ammonium ion and phosphates. The research conducted showed that the quality of treated water was affected by the degree of pollution of raw water and the use of appropriate stages of the process system which removed impurities and neutralised pathogenic microorganisms.
Spatial and social conditions for the location of agricultural biogas plants in Poland (case study)
Authors: Kowalczyk-Juśko Alina , Listosz Agnieszka , Flisiak Monika
Published: February 2019

Biogas production in Poland is controversial. There is a lot of interest in the construction of installations of various scale, and protests of local communities take place at the same time. Residents do not agree to the construction of biogas plants due to the fear of nuisance related to its functioning. This work is a case study of the area of Kamionka – the rural commune in Poland, in terms of the possibility of locating an agricultural biogas plant. The main sources of substrates for biogas production in the commune were determined. When selecting the appropriate location for an agricultural biogas plant, the focus was on the areas designated in the “Study of conditions and directions for spatial development” as areas with the approval of locating devices generating energy from renewable sources. These properties were analyzed in terms of substrate availability (which are waste from animal production, fruit pomace, waste from processing, biomass of plants grown intentionally), plot size, infrastructure status and distance from protected areas. On this basis, one location was chosen that meets all those criteria. Surveys have shown that residents are afraid of unpleasant smell, noise, emerging waste and explosion risk. Nevertheless, the majority of respondents declared willingness to cooperate with the biogas plant.
Speed Control of an Induction Motor Fed by an Inverter Using dSPACE Controller
Authors: Janiga Srinivasrao , Syed Sarfaraz Nawaz , Tummala Suresh Kumar , Pinni Srinivasa Varma
Published: February 2019

This paper presents the design and implementation of Inverter system for driving three phase Induction motor using DSPACE DS1104 controller with the controlling objective space vector pulse width modulation (SVPWM) technique. AC motor drives are commonly used over DC motor drives because of their more advantages. Induction motor is the most commonly used AC motor drive for various industrial and domestic applications. The project will be commenced by a basic understanding of SVPWM inverter, components used in the design and study the mathematical equations of the Induction motor. The performance of SVPWM based Induction motor (IM) in open loop is presented with simulation. Here the hardware implementation of the three phase inverter which is fed to a three phase induction motor driven by DSPACE CP1104 is been implemented.
Speed Control of DC Motor using Fuzzy Logic Controller by PCI 6221 with MATLAB
Authors: Rajagiri Anil Kumar , MN Sandhya Rani , Nawaz Syed Sarfaraz , T Suresh Kumar
Published: February 2019

This thesis demonstrates the importance of Fuzzy Logic Controller. The operation of a DC motor is performed using Fuzzy Logic Controller (FLC) in MATLAB environment. Fuzzy Logic is one of the most successful applications of fuzzy set in which the variables are linguistic rather than numeric. A Fuzzy Logic Controller (FLC) is based on a set of control rules (fuzzy rules) among linguistic variables. The proposed fuzzy controller results in a better response compared to the normal response of DC motor. This thesis consists of two parts; software and hardware implementation. The software part aims to design and develop a Fuzzy Logic Controller in MATLAB Simulink. The hardware Part Consist of DC motor Driver and PCI 6221. The DC drive is used to convert AC voltage into variable DC voltage PCI 6221 is used as the hardware interface between Hardware and Software.
Optimal Operation of Microgrid considering Renewable Energy Sources, Electric Vehicles and Demand Response
Authors: Salkuti Surender Reddy
Published: February 2019

This paper proposes a new optimal operation of Microgrids (MGs) in a distribution system with wind energy generators (WEGs), solar photovoltaic (PV) energy systems, battery energy storage (BES) systems, electric vehicles (EVs) and demand response (DR). To reduce the fluctuations of wind, solar PV powers and load demands, the BES systems and DR are utilized in the proposed hybrid system. The detailed modeling of WEGs, solar PV units, load demands, BES systems and EVs has been presented in this paper. The objective considered here is the minimization of total operating cost of microgrid, and it is formulated by considering the cost of power exchange between the main power grid and microgrid, cost of wind and solar PV energy systems, cost of BES systems, EVs and the cost due to the DR in the system. Simulations are performed on a test microgrid, and they are implemented using GAMS software. Various case studies are performed with and without considering the proposed hybrid system.
Extensive review on Laminated bus bar for low and high power applications
Authors: Singh Prashant B.T. , Babu Bobba Phaneendra , Suresh K. , Varghese Benny J.
Published: February 2019

This paper explains about wide range of applications for Laminated Bus Bar used for high and low power applications. Authors also explains ways to effective utilize laminated bus bar when compared to conventional bus bar. Laminated bus bars are designed with low stray inductance and high capacitance with a uniform current distribution in conducting plate. Parameters like Length, Width, material thickness and other miscellaneous parameters effect Laminated bus bar performance. With a proper design of Laminated bus bar it can best utilized, laminated bus bar are suitable for many low and high power applications which are discussed in this paper. Replacing conventional bus bar with laminated bus bar additional advantages are achieved like lighter weight, less space and lower maintenance.
Analysis and Design of PMBLDC Motor for Three Wheeler Electric Vehicle Application
Authors: Sandeep V. , Shastri Sharankumar
Published: February 2019

This paper deals with analysis and design of permanent magnet brushless dc machine (PMBLDCM), primarily aimed for three wheeler applications. The motor sizing accounts for the forces acting on the motor and the design variables such as number of stator and rotor slots, stator and rotor dimensioning, air-gap approximation, slot sizing, flux per pole and permanent magnet sizing has been explained using simplified equations. The designed motor rated at 1.5 kW, 3000 rpm, 120 V radial flux surface mounted permanent magnet rotor, is then assessed using analytical tools for design such as ANSYS’s RMXprt to verify the analytically obtained results. These results are then verified using the computer aided analysis tool, finite element analysis, using ANSYS Maxwell, to obtain the electromagnetic characteristics of the motor for further modification of design.
Smart helmet for safe driving
Authors: Shravya Keesari , Mandapati Yamini , Keerthi Donuru , Harika Kothapu , Senapati Ranjan K.
Published: February 2019

A smart helmet is a type of protective headgear used by the rider which makes bike driving safer than before. The main purpose of this helmet is to provide safety for the rider. This can be implemented by using advanced features like alcohol detection, accident identification, location tracking, use as a hands free device, fall detection. This makes it not only a smart helmet but also a feature of a smart bike. It is compulsory to wear the helmet, without which the ignition switch cannot turn ON. An RF Module can be used as wireless link for communication between transmitter and receiver. If the rider is drunk the ignition gets automatically locked, and sends a message to the registered number with his current location. In case of an accident it will send a message through GSM along with location with the help of GPS module. The distinctive utility of project is fall detection; if the rider falls down from the bike it sends a message.
Recent progress in angle-insensitive narrowband and broadband metamaterial absorbers
Authors: Ghosh Saptarshi , Nguyen Toan Trung , Lim Sungjoon
Published: February 2019

Recent progress in angle-insensitive narrowband and broadband metamaterial absorbers is presented herein. Initially, a few narrowband structures are described along with their absorption mechanisms. A bandwidth-enhanced absorber, conceptually derived from the existing narrowband geometry, is also discussed. Finally, several broadband absorbers having wide absorption bandwidths across different microwave frequency ranges are illustrated. The reported structures are primarily designed to exhibit high angularly stable responses suitable for practical applications. Furthermore, their geometries are fourfold symmetric, thereby displaying polarization-independent characteristics. Experimental verifications of the designed absorbers have been confirmed under normal and oblique incidences. The angle insensitivity, polarization independence, flexible absorption bandwidths (from narrowband to broadband), and commercial feasibility of the reported structures might establish them as potential candidates for manifold absorber applications.
Effect of Double Pulse MIG Welding on Porosity Formation on Aluminium 5083 Fillet Joint
Authors: Warinsiriruk Eakkachai , Greebmalai Jukkapun , Sangsuriyun Montri
Published: February 2019

In this article, parameters of Double-Pulse Metal Inert Gas Welding (DP-MIG) was used for minimising a porosity formation in a T-joint fillet weld. AA5083-H112 aluminium alloy (Non-heat treatable series) with the plate thickness of 10 millimetres is base metal for this study. Welding consumables were filler wire ER5356 with a diameter of 1.2 millimetres and shielded by industrial argon gas. Three majorities parameter of DP-MIG were Delta wire feed (m/min), Frequency (Hz) and Duty cycle (%). Measurable signal current pattern and opened porosity on the fractured surface were couple observed to study their relationships. An appropriate image processing technique was employed to quantitative measuring and calculating a size grouping area of several opened porosities overall weld length, precisely. The result found that the optimal was used a low-level of Delta wire feed of 0.8 m/min, a high-level of a frequency of 5.0 Hz, a mid-level of the duty cycle 30 % and a high travel speed 60 cm/min could minimise the porosity formation with complete penetration.
Welding Cylinder Head: The Effect of Filler Variations and Post Weld Heat Treatment (PWHT) on Microstructure and Mechanical Properties on TIG Welded Cast Iron FC 250
Authors: Jatimurti Wikan , Hidayat Mas Irfan P. , Rochiem Rochman , Pasca Muna Meilati
Published: February 2019

Cylinder head made from grey cast iron, is one of critical engine part which work on high temperature and pressure. The condition which occurs continuously during engine operation causes wear which identified as a fretting failure. Therefore repairing process is needed by using Tungsten Inert Gas (TIG) welding. By considering the working condition and the materials, welding parameters are used 140A current, 100% Argon, DCEP and preheat at 250°C. The welding process is done on specimen sample of cylinder head which fretting failure by using Ni-CI, NiFe, NiFe-1 dan 308L filler variation for each specimen and done by PWHT at temperature 650°C which holding time 90 minutes. Visual test, macroscopic test, microscopic test and hardness test already done in this research. The results are there is no defect such as crack, porosity, undercut, and lack of fusion on the visual and macroscopic test. On microscopic test, there is the brittle phase (martensite) in HAZ at Non-PWHT specimen, but after PWHT the martensite transform became martempered phase. FC250 standard hardness value is about 170-235HB, and the result is the hardness value of non-PWHT specimen higher than the standard in HAZ, and the high hardness value of PWHT specimen on weld metal by using NiFe, NiFe-1 and 308L. So from the filler variation, Ni-CI filler with PWHT is on standard either on phase or on hardness value
Gas Metal Arc Root Welding of Pearlitic Rails Using Magnetic Arc Deflection
Authors: Weingrill Leonhard , Schwald Martin , Frühstück David , Faustmann Clemens , Enzinger Norbert
Published: February 2019

Magnetic arc deflection was applied to improve gas metal arc root welds on R260 pearlitic rail steel foot samples. During laboratory welding trials parameter optimization was carried out which comprised the welding current, voltage and speed, layer sequence, filler wire diameter, and the external magnetic field. Results were evaluated by visual inspection, and the lateral and diagonal penetration in cross-sections, as well as the microstructure and the hardness in the HAZ. Additionally, the influence of the external magnetic field on the process was studied using a high-speed camera. Overall best results were finally obtained in high welding current spray arc mode (380-400A) with the 1,6mm solid wire and at high welding speed (65cm/min) and two pass per layer sequence, in combination with maximum 30mT magnetic flux density and increased welding voltage (30-31V) for longer arc. A continuously well-formed root with sufficient lateral penetration was achieved and a smooth transition from base metal to weld metal at the lower edges could be achieved. Inside base metal HAZ the microstructure was fully pearlitic and no soft zone occurred. Furthermore, the size of the HAZ was in comparison to aluminothermic weld reduced by more than 75% in comparison to an AT rail weld.
The Effect of Ultrasonic Energy on Joint Characterization in Ultrasonic Spot Welding Multilayer Tabs Used in Lithium-ion Battery Manufacturing
Authors: Ma Z.N. , Zhang Y.S.
Published: February 2019

Lithium-ion battery for electric vehicles contains a large number of battery tabs with multiple and thin sheets. Dissimilar metals are often used for different electrodes, for example, the copper and nickel are often used for negative electrode and the aluminum is often used for positive electrode. Meanwhile the thickness of metal sheets are various at different locations. Ultrasonic spot welding is very capable of welding similar and dissimilar combinations. However, there are less heat generation and plastic deformation in the bottom interfaces where ultrasonic energy is difficult to reach. This will result in the unbonded region occurrence caused by ultrasonic energy attenuation.

In this work, experimental investigation was conducted to identify the effect of ultrasonic energy on joint characterization in ultrasonic welding multiple tabs by comparing the plastic deformation in different layers and various joint interfaces. Two sonotrodes with different knurl size were used to produce the welding energy for the tabs joining. Samples were cross-sectioned along vibration direction to obtain hardness profiles and metallographic maps. The hardness profile can be used to identify the changes of grain morphology. Hardness and grain size changes in different layers were also studied to reflect how ultrasonic energy decrease from top to bottom in battery tabs. Thereby, the relationship between material attributes and ultrasonic energy loss was established based on the experimental results.
Effect of Rotational Speed and Flat Tool Diameter on the Zn Distribution of the Dissimilar Metals Friction Stir Spot Welded between Aluminum Alloy 5083 H321 and Galvanized Steel
Authors: Adhi Guna Bintang , Muhayat Nurul , Triyono
Published: February 2019

Friction stir spot welding (FSSW) was developed to join the dissimilar materials as an alternative for replacing the resistance spot welding (RSW). In the case of dissimilar metals welded between aluminum and galvanized steel, Zn can decompose and diffuse in both steel and aluminum so it can increase the joint strength. Due to this reason, it is important to explore the Zn distribution based on the parameter of the friction stir spot welding. The lap joint configuration was used in this work where aluminum plate was placed on the top of steel. Aluminum thickness was 3 mm, while steel thickness was 1 mm. The constant depth of plunge, dwell time, and penetration rate were 2.7 mm, 3 seconds, and 0.9 mm/sec respectively. Flat tool with diameters of 10 mm, 12 mm and 14 mm were used for FSSW processes and for each flat tool diameter, four levels of the rotational speed of 1000 rpm, 1200 rpm, 1600 rpm and 2000 rpm were performed. The Zn distribution was evaluated using the SEM and EDS analysis. Due to the heat generation during FSSW process, materials around the tools will soften and then flow to follow the centrifugal force. The rotational speed and the flat tool diameter affected the distance and the shape of Zn diffusion flow. The distance of Zn diffusion both horizontal and vertical direction increased as increasing the rotational speed and the flat tool diameter.
Effect of Nickel on the Microstructure, Hardness and Impact Toughness of SM570-TMC Weld Metals
Authors: Setiyanto Nova Arief , Oktadinata Herry , Winarto Winarto
Published: February 2019

SM570-TMC steel was applied in the various fields of steel construction where higher strength is required than conventional mild steel. This steel is commonly fabricated by fusion welding where flux-cored arc welding (FCAW) is preferred due to efficiency consideration. In this study, 14 mm thickness of SM570-TMC steel was butt weld by FCAW using three electrode wires with different nickel content (0% Ni, 1% Ni, 1.5% Ni). The microstructure of weldments was studied using an optical microscope. The hardness distribution tests were performed in the heat affected zone, parent metal and weld metal. And impact toughness of weld metals were measured at temperatures of 25 °C, 0 °C and -20 °C. The results show the steel plate welded using welding wire containing 1% Ni provides more superior impact toughness in the weld metal than welding wire 0% Ni, while the impact toughness of the sample which welded using welding wire containing 1.5% tend to decrease. Nickel element which deposited to weld metal by using welding wires containing 1% Ni has improved the impact toughness, but 1.5% Ni may too high which deteriorate impact toughness.
Challenges and Opportunities in Remote Laser Welding of Steel to Aluminium
Authors: Kotadia Hiren R. , Franciosa Pasquale , Ceglarek Dariusz
Published: February 2019

In the last two decades, the automotive industry has been facing demands to reduce fuel consumption and to meet CO2 emissions through applications of lightweight materials. Therefore, aluminium alloys have replaced substantial amounts of steel; and they are receiving significant attention to achieve greenhouse emission targets. However, a critical factor in applications of advanced aluminium in automotive Body in White (BIW) designs depends on availability of cost effective and high performance joining processes. Currently, a Self-Pierce Riveting (SPR) process is extensively used for aluminium BIW sheet metal parts joining which is expensive, additionally increase the weight of the vehicle and cause inefficiency in manufacturing operations. As aluminium alloys are difficult to weld by conventional technologies such as electrical resistance spot welding, MIG arc welding etc., various joining technologies had proposed to weld aluminium alloys and dissimilar alloys over the years. Often, these technologies restrict design flexibility and are expensive for mass production. In this context, Remote Laser Welding (RLW) has gained popularity because of its distinct advantages such as design flexibility, production speed, material and cost savings. This paper provides a critical review of challenges and opportunities for application of RLW to dissimilar metal welding of steel to aluminium. Next steps of research and development are also highlighted.
Failure Mode Prediction of Resistance Spot Welded Quenching and Partitioning Steel
Authors: Luo Cheng , Zhang Yansong
Published: February 2019

In recent years, a novel Advanced High-Strength Steels called quenching and partitioning (Q&P) steel has been applied in the automotive industry because its good combination of strength and ductility. In this study, an experimental setup by adopting digital image correlation (DIC) method was firstly developed to establish the constitutive relationship of fusion zone in the spot welds produced by Q&P980. Stress-strain relationship extracted from the tensile bar within the fusion zone and compared the results to that of base metal. The fusion zone of Q&P980 found to have a higher tensile strength and similar elongation compared with base metal. A numerical model established to predict the failure mode of joints generated by Q&P980 after obtaining the constitutive relationship of fusion zone. The predicted failure mode was in good coherence with the experimental results under the lap-shear test conditions. The developed FE model was proven efficient in tensile strength and failure mode characterization of spot welded specimen. This study could provide solutions to maintain or even improve vehicle crashworthiness of lightweight vehicle structures.
Failure Analysis of Tube Radiant Heater Hot Oil in Refinery Industry
Authors: Dimastiar Moch Ardi , Taufik Ahmad , Syahrial Anne Zulfia
Published: February 2019

Heater, known as a furnace or fired heater is used to heat the oil which flows through tubes around a flame. When the tubes are failed, the fired heater reliability is affected. This paper investigates the probable cause/ causes of the radiant tube failure in the fired heater. In that context, depth analysis is conducted as part of the investigative studies, involve visual observation and dimensional measurement, metallographic examination, and chemical analysis. Finally, it has been concluded that the tube radiant has mainly failed due to crevice corrosion. In the other side, spherodization and external corrosion are also found as other failure contributors.
Selection of Welding Process for Repairing Shredder Hammer by Integrated Data Envelopment Analysis (DEA) and P-robust Technique
Authors: Wisnu Wardana Rahmad , Warinsiriruk Eakkachai , Joy-A-Ka Sutep
Published: February 2019

The Selection of the welding process is one of the most significant decision-making problems, and it involves a wide range of information following the type of product. Hence, the automation of knowledge through a knowledge-based system will significantly enhance the decision-making process and simplify for identifying the most appropriate welding processes. The aims of this paper for explicates a knowledge-based system developed for recognising the most suitable welding processes for repairing shredder hammer by using data envelopment analysis (DEA) and p-robust technique. The proposed approach is used for ranking six welding processes which are commonly used, namely shielded metal arc welding (SMAW), flux cored arc welding (FCAW), submerged arc welding (SAW), oxyacetylene gas welding (OAW), gas tungsten arc welding (GTAW), and gas metal arc welding (GMAW). In order to determine the best welding process among competitive welding processes for repairing of shredder hammer, ten parameters are used, namely the availability of consumable, welding process type (manual and automatic), flexibility of welding position, weld-ability on base metal, initial preparation required, welding procedures, post-weld cleaning, capital cost, operating factor, and deposition rate. Furthermore, the sensitivity analysis of regret value (p) is investigated in three cases proposed.
Effect of Squeeze-out and Sizing Ratio to The Residual Circumferential Stress of HFW Pipe
Authors: Harianto Siens , Susilaputra Elang , Darto Peter , Fandika Ardian
Published: February 2019

Residual circumferential stress originates from pipe forming process has a negative impact on the pressure carrying capacity; therefore it is necessary to keep the level of residual stress as low as possible and distributed uniformly around the pipe. Manufacturing of HFW (High-Frequency Welded) pipe involves pinching, bending, forming, welding, squeezing, sizing and straightening processes in several stages which produce both elastic and plastic deformation. Those processes produce residual stresses in the pipe wall in the circumferential and longitudinal directions. This paper presents the result of the trial test to investigate the effect of squeeze-out (SO) and the sizing ratio (SR) to the residual circumferential stress on HFW pipe. The trial was performed at PT INDAL STEEL PIPE (ISP) pipe mill, on pipe API 5L L360MO PSL2, nominal Outside Diameter (OD) 273 mm, wall thickness 12.7 mm. The SO was 0.7t and 0.9t, while the SR was set at 0.5 %, 0.8 %, and 1.0 %.
Impact Toughness of Gas Metal Arc Welded HY-80 Steel Plate at Sub-zero Temperatures
Authors: Oktadinata Herry , Winarto Winarto
Published: February 2019

Various welding methods are widely applied in large fabrication of high strength steel. However, commonly the problem occurs where a coarse grain is formed near fusion zone causing reduce the impact toughness due to the weld joint become brittle. Ductility and toughness in a coarse grain heat affected zone (CGHAZ) is low due to the formation of coarsening grain size. The objective of this research is to investigate the microstructure evolution, impact toughness and fracture appearance at sub-zero temperatures of the high strength steel arc welded. The steel that used in this experiment is a HY-80 steel welded by gas metal arc welding (GMAW) with a mixture of argon and carbon dioxide (90%Ar and 10%CO2) and ER100S solid wire. Microstructure observation and Charpy V-notch (CVN) tests were performed on the weld joint which consist of base metal (BM), heat affected zone (HAZ), and weld metal (WM). The CVN tests on the HY-80 steel plate at various temperatures (20, -20, -60 and -80 °C) show impact toughness decrease when the test temperature decrease. The CVN tests on the HY-80 weld joint at a temperature of 80 °C show the lowest impact toughness was measured at WM (61 J) and followed fusion line-FL (101 J) with brittle fracture appearance.