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Laser cladding uses a high-energy laser beam as a heat source to rapidly melt and solidify the cladding material onto the substrate to form a high-performance coating. This technology provides an efficient and economical method to repair and remanufacture precision equipment such as engines and spacecraft. However, the inherent non-equilibrium solidification properties of laser cladding often lead to problems such as coating anisotropy, high porosity, and elemental segregation. Optimizing process parameters and heat treatment do not always eliminate these defects. Therefore, it is necessary to seek a more appropriate solution. Introducing laser remelting on the surface or between the layers of the coating to cause it to remelt and redistribute can refine the grain size, reduce defects, and improve the uniformity of the composition, thus enhancing the performance of the coating. This paper reviews and summarizes the application and development status of laser remelting technology in laser cladding and discusses it in terms of surface quality, hardness, wear resistance, and corrosion resistance of the coating. It also identifies the potential of external field-assisted laser remelting technology in further optimizing coating performance. Finally, based on the review, suggestions are provided for selecting remelting parameters. [ABSTRACT FROM AUTHOR]

Maintenance is the protection of machines and equipment to maximize their availability. This area has become so prominent that today it occupies an important place in the organizational structure and is even one of the important areas for maintaining and increasing productivity. As the maintenance industry has improved, so has the staff that performs it, from versatile technicians to specialists who fully understand their field of work (Instituto Tecnológico Superior de Teziutlán, 2012). It has become one of the basic needs of a company or organization since technological advances have become a necessity for its growth and development. Machines and equipment in good condition are critical for the optimal operation of the process, which has led companies to consider implementing a maintenance program that helps not only to carry out repairs and avoid breakdowns, but also to identify possible causes and breakdowns. of the machines. in downtime or production Find defects before unplanned downtime, reducing corrective maintenance costs. [ABSTRACT FROM AUTHOR]

Production tests on test-benches are mandatory before aircraft engines are delivered, as the measurements taken during the tests determine whether the engine meets the requirements. They are essential for both aircraft and engine manufacturers and the latter can use them to obtain a comprehensive picture of the performance of each engine. Such tests involve numerous measurements, the analysis of which is a challenging task. The study presented in this paper aims to detect possible biases introduced by the instruments used to measure the engines during the tests, especially the test-bench itself. A method is proposed to correct these biases. At the end, it will be necessary to verify that the data are corrected, ie that the measurements no longer depend on the test-bench on which they were made. This analysis is the follow-up of previous work on thrust tendency estimation[1]. [ABSTRACT FROM AUTHOR]

Aftertreatment technologies in Tier 4 off-road engines have resulted in significant emission reductions compared to older tier engines without aftertreatments. The appropriate characterization of Tier 4 engine emissions in consideration of aftertreatment operation is important for projecting emissions and developing mitigation strategies. The current method of aggregating emissions over an entire duty cycle and averaging them by engine load has a limitation in developing emission profiles over various duty cycles of Tier 4 engines, especially at low-load operations, where aftertreatment control for NOx may not be effective. In this study, an engine power binning method was developed to characterize emissions for Tier 4 construction equipment with aftertreatment systems, especially at low-power operating conditions. This binning method was applied to real-time emissions and activity data for four different types of Tier 4 construction equipment. Results show that low-power operations (<20% engine power) are responsible for 38–60% NOx and 11–51% of PM2.5 emissions depending on the equipment types. These results underscore the need for controlling NOx emissions during low-power operations. PM2.5 EFs for non-DPF backhoes were one to two orders of magnitude greater than all the other equipment due to the lack of a DPF, despite being certified to the same PM2.5 standard. This shows the benefits of DPFs on construction equipment and that they are substantial in reducing PM2.5 emissions. Estimated emission differences between using the binning and the averaging methods were 49–86% and 16–82% for NOx and PM2.5, respectively. These differences may change once the binning method is applied to larger emission datasets obtained from real-world vocational activities. [ABSTRACT FROM AUTHOR]

Earthmoving operations employ heavy-duty vehicles, including trucks and scrapers, to transport soil and rock on and off construction sites. Such construction activities are commonly scheduled and paid for based on the amount of earth moved. A number of metric and volumetric tools and techniques, including weighbridges, load–volume scanners (LVS), and strain gauges, have been developed to measure the payload of vehicles. These methods are costly, time-consuming, and labor-intensive, and may affect the production rate and cost of construction projects. This study develops an automatic mass estimation technique for on-road construction vehicles considering both operational and engine data. Acceleration rate, speed, and road slope are investigated as the operational variables, while engine load is considered as an engine attribute to estimate vehicle mass. A global positioning system-aided inertial navigation system (GPS-INS) and an engine data logger are integrated to collect the field data. Experiments are conducted on several construction vehicles to collect a wide range of data under various operational conditions. After assuring the quality of field data obtained in this study, artificial neural networks (ANNs) were developed to model the mass of construction equipment based on operational and engine parameters. The model was validated by comparing the estimated mass data with the actual values measured by a weighbridge in the experiment. The results show that the proposed model achieves greater than 90% accuracy in predicting the mass of on-road construction vehicles. [ABSTRACT FROM AUTHOR]

This study covers the issues of the security system in civil aviation. The relevance of the topic is conditioned by a qualitatively new approach to the design of civil aviation, since the modern equipment has the means intended for rescue directly in the area of contact of an emergency aircraft with the ground. When hitting the ground, as a rule, the lower part of the airframe is crushed, the fuselages break in the centre wing section, and the interior equipment breaking off is very traumatic to passengers, the engines are extremely fire and explosion dangerous, which leads to an emergency situation developing into a catastrophic one. The purpose of the study is to investigate the existing security system of a civil aircraft and develop the modification of aviation equipment with the help of collective rescue systems. Two main areas of application of collective rescue systems in aviation technology are analysed. As a solution to the problem at hand, a modification in the form of a parachute system of collective rescue is proposed. A detailed description of the system operation with the use of the necessary calculations for weight, aerodynamic and similar costs is given. The system under study relates to aviation technology and can be used in the development of transport (passenger, cargo, business class, etc.) aircraft. The proposed modification would significantly increase the level of flight safety due to a preventive measure that would exclude the contact area of the emergency aircraft with the ground. [ABSTRACT FROM AUTHOR]

Hybrid and electric vehicle (HEV/EV) technology is reasonably mature at this time, with a few million vehicles around in the world, and there is a significant amount of literature in the public domain on this subject. However, there is not enough literature on the application of this technology for off-road vehicles, including construction equipment, other industrial utility vehicles, and nonautomotive applications, such as a locomotive, ships, or airborne vehicles. With this in mind, the author presents here the topic and its current status. In addition, the author discusses the issue related to the decision-making process before the above technology is introduced for any HEV/EV application so that one is assured that the technology will bring benefit if applied for a particular purpose. [ABSTRACT FROM AUTHOR]

The aim of the article is to present the environmental effects of changes in material composition in selected internal combustion engines used in passenger cars using LCA analysis. The levels of energy consumption and emissions of pollutants related to material inputs occurring at the stage of engine production have been determined. The simplified LCA model presented in the paper shows the energy consumption and total CO2 and SO2 emissions on the basis of the mass of materials from which the engine is made. The research results presented in the paper give a picture of a modern passenger car engine on the basis of wear and the degree of recovery of materials used for its construction. [ABSTRACT FROM AUTHOR]

In this study, effective parameters on viscosity of a suitable oil for lubrication of heavy-duty engines (vehicles that are in use in construction, farm, and logging equipment, semi-trucks, delivery trucks, etc.) are studied. SAE50 as a single-degree engine oil is examined in present experimental work. The mentioned engine oil is enriched by MgO and MWCNT nanoparticles (NPs). The nanofluid was prepared in six solid volume fractions (SVF) and in temperature range of 25–50 °C. The results showed the viscosity dependence on shear rate, so nanolubricant has a non-Newtonian behavior. 2–4% Viscosity reduction in concentrations of 0.0625% and 0.125% reported in comparison with viscosity of pure fluid. Also sensitivity analysis of viscosity measurement was lower than 1% for all investigated conditions. To lower experimental costs, a mathematical correlation was proposed to predict the viscosity. The R2 was considered as criterion for accuracy of proposed correlation. Having amount of 0.9995 for R2 shows accommodation of correlation predictions with experimental results. Also maximum deviation of < 3% indicates that the proposed correlation has a high accuracy. [ABSTRACT FROM AUTHOR]

Load Haul Dump (LHD) equipment, haulers, and locomotives are essential to both hard and soft rock mining. Key performance indicators were calculated for both diesel and electric LHDs using the data provided by a multinational mining company operating metal mines. Battery-powered vehicles, having both the advantage of low maintenance and no tether to haul, showed an improvement in uptime. The electric fleet was, on average, operational 11 h longer than diesel vehicles before they are pulled off for maintenance. The results from comparing diesel and electric equipment show that the best equipment would be a fusion of the reliability of electric vehicles and the mobility of diesel equipment, both being attributes of battery powered equipment. Battery-powered vehicles are constantly improving and will only increase their prowess over diesel equipment. [ABSTRACT FROM AUTHOR]

Transporting industry is having an important influence on the nations' progress. The states that having long shoreline are taking advantage of their locations in using sea transportations which is more economical than other types of transportations. One of the most economical marine transport is the diesel fueling engines. This paper is to optimize the PID controller to control the speed of the engine overcoming the navigation environmental changes such as waves, winds and other effective external factors as well as the vessel internal changes such as the shipment load, equipment's conditions etc. PID is optimized through the optimum selection of its parameters (KP, KI and KD). A Simulink/MatLab model of the system is designed for this purpose. The Hybrid IWOPSO (HIWOPSO) algorithm is used for finding the optimum values of the PID parameters. The engine step response with these parameters is compared to the responses with those obtained by the IWO and PSO besides the Fuzzy Logic Control (FLC). [ABSTRACT FROM AUTHOR]

Fault diagnosis (the process of finding out whether system or equipment is in fault and where the corresponding fault is by using various inspection and testing method) on the engine is a typical information fusion (the process of integrating multiple data sources to produce more consistent, accurate, and useful information than that provided by any individual data source) problem where the information can be obtained from engine vibration, temperature, pressure, etc. Due to the efficiency of data fusion, Dempster–Shafer evidence theory is widely used in fault diagnosis. One key step to using evidence theory is to obtain the so-called basic probability assignment (BPA), or belief function. In this article, a new mathematical framework is presented to determine weighted BPA (WBPA). This WBPA function is obtained by weighting the distance between sample data and empirical data. With the assumption that the empirical data are normally distributed, the weighting factor can be determined. Then, the WBPA can be combined with D–S evidence theory to determine the status of the engine. Finally, a case in fault diagnosis and comparison with Song and Jiang (Adv Mech Eng 8(10):1–16, 2016) method illustrate the efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

Recently, there are emphasized to support the maintenance and management system of vessels using acquired data from engine part equipment. But, there are limitations for data exchange and management. To solve the problem, the ISO published ISO 19847 and 19848. In this paper, we analyze the ISO 19848 requirements related to identify data channel ID for ship equipment, and propose the examples for applying encoding techniques. In addition, we suggest the proposed technique for applying of managing the failure and maintenance type of the ship's engine part facilities by examples. If this method is applied, the vessel`s equipment can exchange data through the sharing of the code table, and express what response is needed or acted, including where the failure occurred. [ABSTRACT FROM AUTHOR]

• Determine the number of vehicles in energy distribution companies. • Predict vehicle fuel consumption in energy distribution companies. • Extra fuel consumption model in vehicles due to weight and engine displacement. • Use the ANN to predict vehicle behavior. Energy distribution companies use various vehicles such as Outage Elimination Maintenance Vehicles (OEMVs), Maintenance Vehicles (MVs) and Supervision Vehicles (SVs) in order to resolve network faults, to conduct inspection, service and maintenance activities and to monitor the integrity of operations. These vehicles have different levels of fuel consumption which concerns companies with regards to the cost and environmental hazards. Hence, it is important to know that a distribution company how many and what types of vehicles do need to predict the fuel consumption of these vehicles. Extra fuel consumption may be required owing to carry unnecessary equipment or used vehicles with large engine volume. Therefore, in this paper, the fuel consumption levels of outage elimination maintenance, maintenance, and supervision vehicles are considered. Then, given the fact that fuel consumption increases with the increase of vehicle weight and Engine Displacement (ED), the extra fuel consumption has been predicted using Artificial Neural Networks (ANNs). In a case study, the total annual fuel cost in the network under consideration is estimated to be $66750. In the case of a 40% increase in vehicle weight, the fuel consumption cost will rise by $24500, and when the engine displacement increases for a 500 CC, the cost rises up $17400 per year. [ABSTRACT FROM AUTHOR]

Purpose: Product sustainability assessment should evaluate the impacts on all three dimensions of sustainability (environment, economy, and society). Life cycle sustainability assessment (LCSA) is a framework that extends life cycle-based product assessment to all three dimensions. Evaluation of trade-off situations poses a challenge within LCSA in a business context, especially if improvement measures for product sustainability lead to higher costs. This paper introduces the concept of the Product Sustainability Budget (PSB) to enable a decision for improvement measures despite of rising costs. It demonstrates a way to create such a PSB and how to combine it with an operationalized LCSA framework at an automotive company. Methods: A survey was carried out asking 250 potential customers of the premium car segment in Germany via Choice-Based-Conjoint-Analysis (CBCA) about their preference of a sustainability interior package in a car. The sustainability package was one of the three specifications of a potential car interior (standard, luxury, sustainability) and was asked along four other attributes (price, drive train, engine power, and consumption). The survey was expanded by an Advanced-Van-Westendorp analysis to ask respondents about their willingness-to-pay (WTP) for such a package. The major findings of the study (take rate and price for the sustainability interior package) were then implemented in a business case logic from which the PSB was created. Results and discussion: Nineteen percent of the entire sample would prefer the sustainability interior package to the other packages (=potential take rate) while the rest (81%) favored the luxury package. The package should be sold to this (potential) target group at price premium of 1.3–1.7% for a middle class limousine (or 0.4–1.1% when corrected for overstated WTP). It could be shown in a theoretical business case logic for such a sustainability package that the profit could be converted to form the PSB, which could compensate an increase in costs caused by a measure to improve product sustainability. The PSB opened up a solution space to identify the ideal set out of several possible improvement measures. Conclusions: The introduction of an LCSA evaluation scheme on component level in combination with the proposed Product Sustainability Budget could enable substantial product sustainability improvement even when costs increase. The combination of an implicit CBCA and an explicit WTP study delivered a sound basis for creating this Product Sustainability Budget. The proposed concept should be applied in a business context to test its viability and additionally investigate customers' WTP for improved social impacts. [ABSTRACT FROM AUTHOR]

• Ship-based carbon capture (SBCC) is a transition solution which can be implemented on short term on diesel or LNG-fuelled vessels. • CAPEX and OPEX are reduced by integrating the thermal energy of the exhaust gas with the stripper reboiler(new bullet point) For the LNG-fuelled ships, the cooling capacity from evaporation of LNG was used for liquefying the captured CO 2. • By using piperazine, the minimal cost of CO 2 capture and liquefaction achieved was 98 €/tonne CO 2. • The feasibility of SBCC is investigated by adapting an existing cargo ship design. The ship stability is maintained. Total shipping carbon emissions were approximately 938 million tonnes CO 2 in 2012. Zero emission shipping options rely on the use of electricity or alternative fuels, such as blue hydrogen or ammonia. However, that requires major modifications to the ships and the logistics of fuel distribution. As a transition solution, which can be implemented on much shorter term; this study presents the technical and economic evaluation for ship-based carbon capture (SBCC) on diesel or LNG-fuelled vessels. Two reference ship engines of 1280 kW and 3000 kW were chosen. The process is simulated using Aspen Plus®, with 30 wt% aqueous monoethanolamine (MEA) and 30 wt% aqueous piperazine (PZ) as solvents. CAPEX and OPEX were reduced by integrating the thermal energy of the exhaust gas with the stripper reboiler for the diesel and LNG powered ships. For the LNG ships, the cooling capacity from evaporation of LNG was used for liquefying the captured CO 2. By using piperazine, which allows CO 2 to be desorbed at higher pressure than MEA, the minimal cost of CO 2 captured achieved was 98 €/tonne CO 2 with a corresponding 1.8 million euros equipment cost for the 3000 kW engine ship. Additionally, the feasibility of SBCC is investigated by adapting an existing cargo ship design (powered by the reference 3000 kW engine) for including the carbon capture process equipment. The capture, compression and storage units are fitted onboard, and the design is modified so that the transport capacity remains the same, while maintaining the ship stability. [ABSTRACT FROM AUTHOR]

Public sector automobile rebuild industry plays an important role towards national economy in developing countries. Nevertheless, productivity of these public sector organizations remains generally very low as compared to private sector organizations which thrive due to competitive market pressures and profitability. This paper attempts to identify reasons for low productivity in public sector automobile rebuild organizations of Pakistan. Towards this end, one of the biggest public sector automobile rebuild organization was selected. Primary data related to productivity measurement was collected from the selected organization. Thereafter, data regarding causes of low productivity was collected qualitatively by conducting semi-structured interviews with open ended questions from thirty two top and middle and supervisor level management professionals. Results indicate that reasons for low productivity in public sector automobile rebuild organizations are diverse variety of vehicles, poor classification/inspection of parts with diluted skill of inspectors, lengthy public procurement procedures, limitation of trading-off between price and acceptable quality of spare parts, improper maintenance, use of outdated tools/test equipment, rework & quality issues, ignorance about productivity cycle, tools and techniques, shortage and imbalance of technical human resource/equipment, unsafe working environment, absence of performance audit, nonagility, limited automation, huge inventories, supply chain anomalies, lack of accountability, bureaucratic culture and deviation from standard engineering practices. [ABSTRACT FROM AUTHOR]

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According to the modification requirement for the flywheel tightening device in the assembly line of a well-known automobile manufacturer, this paper designs an electrical control system for flywheel tightening device with the Schneider TXS57 series controller and the XBTGK2330 touch screen as the control core. In order to achieve the precise control over the torque, angle and other parameters during bolt tightening, this paper performs some basic mechanics analysis and experiment on the current bolt tightening methods and techniques, and finally selects the torque-angle method. Under this method, two wrenches are added and tightening is performed according to settings, which makes up for the insufficient capacity of the company, and helps ensure its normal production and operation. The system studied and designed in this paper is of great significance to promoting the application of flywheel tightening devices in automobile engine assembly. It can manage and control tightening data at limited costs, which is an excellent solution for the information construction at factory. [ABSTRACT FROM AUTHOR]