Heavy Engine Research Articles

Pembuatan Media Pembelajaran dan Pengujian Motor Starting System (207-1556 CW)

Starting motors have an important role in running heavy equipment engines, accuracy in testing starting motor components is a very important factor. Practical learning using starting motor testing media is used to practice starting motor assembly and disassembly. The problems experienced by students in this course are limited practical equipment and lack of student skills regarding assembly and disassembly of motor starting systems. The aim of this research is to create learning media for testing motor starting systems and create a motor starting system testing guide so that it can be used as a practical tool in heavy equipment maintenance workshops. Experimental methods and work processes include: 1) determining materials, 2) designing the frame, 3) working on the frame, 4) making disassembly guides, testing, and starting motor assembly. The results of this research are that the learning media is equipped with the main components of the motor starting system, measurements that display motor starting system testing information, namely: the process of disassembly, testing and assembly of the starting motor, so that this learning media can increase students' understanding of the function and operation of the starting motor. system, as well as providing practical experience in testing and understanding related components.

Oil Consumption Optimization for Heavy Duty Engine Using Design for Six Sigma

Oil Consumption Optimization for Heavy Duty Engine Using Design for Six Sigma

The Effect of Engine Noise on the Comfort of WA-360 Loader Heavy Equipment Operators Based on Capacity and Distance of 100, 150 and 200 cm

The existence of a limited volume of machine room and coupled with the existence of various kinds of machinery in it, both main drive machinery such as the main motor and other supporting machinery such as electric motors, compressors, pumps and so on, all of which are sources of noise, will cause high noise noise. Where heavy equipment is a tool used to simplify the work process so that it becomes faster, easier and the results are in accordance with expectations and one example is the Whell Loader WA-360 heavy machine. Therefore, research is needed to measure the level of noise produced by the Whell Loader WA-360 heavy equipment engine to operator comfort. According to NAB According to Kepmenaker No. per-51/MEN/1999,2008 and SNI 16-7063-2004, the noise level that results in hearing damage of 90 dB for workers who are working for 8 hours per day. That the threshold value for the noise of the combustion chamber of the Wheel Loader WA-360 heavy equipment engine with a bucket capacity of 3.4 and 5 tons produces a noise level of 106.5 dB with a hearing scale and it is recommended that the operator of the Whell Loader heavy equipment use Earphones while doing work.

Larsen & Toubro: constructing competencies and building the nation

Learning outcomes The following are the objectives of the case study: building and leveraging core competence, realizing the strategic advantage of incumbency and contribution to nation building as a business potential. Case overview/synopsis Larsen and Toubro (L&T) started as a trading company in 1938. By 2023 L&T was a mammoth infrastructure company with a market cap INR 4,750bn operating 800–1,000 projects in engineering and construction at any point in time. It also worked in the domain of hydrocarbons, power and heavy engineering including defence engineering, financial services and development projects supported by technology. The company went through several phases of environmental disruptions in the form of the Second World War and India’s independence, which brought several opportunities for growth. L&T built competencies to leverage these opportunities, which also contributed to the nation building efforts in India. In 2023, several changes were occurring in the ecosystem in the form of energy changes, sustainability becoming a way of life and digitalization impacting every aspect of business. The managing director and chief executive officer Mr S.N. Subrahmanyan reiterated the need to focus on performance to make L&T a global leader in futuristic tech-driven engineering and solutions. He faced three major challenges – reducing exposure in non-core businesses, adopting technology to strengthen traditional business and leveraging the competence built over 85 years to improve the performance of L&T, while contributing to nation building. Complexity academic level This case study is suitable for MBA and executive programmes. Supplementary materials Teaching notes are available for educators only. Video of protagonist in conversation with Anant Maheshwari, President Microsoft India discussing the future plans of L&T for adopting new age technology. The video is available at the following YouTube link https://www.youtube.com/watch?v=OKb-_z_ch4E Subject code CSS 11: Strategy.

Prevalence of hearing loss among noise-exposed U.S. workers within the Construction sector, 2010–2019

Background: The purpose of this cross-sectional study is to estimate the prevalence of hearing loss among noise-exposed U.S. workers during 2010–2019 within the Construction sector. Methods: Audiograms for 26,653 workers at 833 Construction companies (and for 1.3 million other workers) were examined. Period prevalence and adjusted risk for hearing loss as compared with a reference industry (Couriers and Messengers) were estimated for the Construction sector and sub-sectors, and all industries combined. Results: The prevalence of hearing loss within the Construction sector was 23% compared to 20% for all industries combined. Several sub-sectors exceeded the overall prevalence and all but two had adjusted risks significantly higher than the reference industry. The sub-sectors with the highest prevalences for hearing loss were: Highway, Street, and Bridge Construction (28%), Site Preparation Contractors (26%), New Single-Family Housing Construction (except Operative Builders) (25%), Oil and Gas Pipeline and Related Structures Construction (25%), and Other Building Finishing Contractors (25%). The sub-sectors with the highest adjusted risks were Industrial Building Construction; Other Heavy and Civil Engineering Construction; Oil and Gas Pipeline and Related Structures Construction; Finish Carpentry Contractors; and Site Preparation Contractors; with risks 62%, 61%, 60%, 59% and 58% higher than the reference industry, respectively. Conclusions: Hearing loss continues to be a significant issue within Construction. Reducing noise exposure is critical, including buying quieter equipment, keeping moving parts oiled and well-maintained, enclosing noise sources, and employing administrative controls to reduce the number of workers in noisy areas. Barriers to workers consistently and correctly wearing their hearing protection also need to be addressed. Practical Applications: Within Construction, hazardous noise is common and the risk of hearing loss is high. This study identified the Construction sub-sectors with the highest prevalences and risks to guide interventions toward workers most in need of prevention and described strategies for reducing exposures.

Model based design of a turbo-compound bottomed to internal combustion engine exhaust gas

Abstract The transportation sector is living a new era, where the conventional powertrains based on thermal engines are flanked by innovative ones, based on electric and hybrid systems. This revolutionizes the behaviour and the driving habits, as well as the figure of the whole propulsive system, which should integrate different energy sources on board and the energy demand for propulsion, auxiliaries, ancillary components, vehicle needs, etc. But, for heavy-duty vehicles, it is very difficult to abandon in the short and mean term the reciprocating combustion engine technology. Also, for passenger cars and light duty vehicles, the pure electric propulsion seems to put in more evidence limits not only technological. In this panorama, the development of very high efficiency engines is mandatory to fit the emissions targets, both referred to pollutant emission and CO2. In this regard, waste heat recovery into mechanical or electrical energy is one of the most promising options to reduce fuel consumption. It is of particular interest for heavy duty engines, where the operation does not suffer so much the transient phases, and hybrid powertrains, where the energy recovered can be stored in electrical form and used for all the necessities of the vehicles. In this paper, a waste heat recovery system based on an additional turbine placed in the exhaust line of a turbocharged internal combustion engine has been studied. The auxiliary turbine is designed thanks to a model-based approach. The performance map of the turbine has been calculated referring to the thermodynamic conditions of the engine exhaust gases as input parameters. The so-designed component is then integrated with an engine model, and the benefits of a turbo-compound technology bottomed to the engine were assessed. In this way, the potential power recoverable from the turbine is evaluated under design and off-design conditions. The integration with engine model allowed to estimate the side effects related to backpressure increase on the engine exhaust manifold (which leads to an overconsumption or an underrating of the engine torque), as well as the equilibrium change on the turbocharger shaft. Definitively, the final overall engine performances are assessed including the need for a bypass which, in certain engine working conditions, must exclude the recovery.

An Analysis of Critical Processes and Employee Challenges at Velmurugan Heavy Engineering Industries (VHEI) Private Limited, Thanjavur

This study investigates the critical processes and challenges faced by employees at Velmurugan Heavy Engineering Pvt. Ltd., located in Sengipatti, Thanjavur. The aim is to identify areas for improvement and provide recommendations to enhance employee performance and organizational effectiveness. Employing a mixed-method approach combining qualitative and quantitative methods, data were collected extensively through surveys, interviews, and observations from a representative sample across departments and hierarchical levels. The findings highlight critical areas such as project management, quality control, communication channels, and performance evaluation. While the organization demonstrates competence in these areas, gaps exist, particularly in streamlined communication and efficient project management. The study also uncovers challenges including unclear role expectations, limited professional development opportunities, inadequate work-life balance, and insufficient recognition and rewards. Recommendations are offered to strengthen communication channels, enhance project management practices, implement employee development programs, promote work-life balance initiatives, and establish a robust recognition and rewards system. Addressing these challenges and implementing recommended strategies has led to improved employee satisfaction, productivity, and overall organizational performance. This study provides valuable insights for Velmurugan Heavy Engineering Pvt. Ltd. to cultivate a positive work environment and foster a highly engaged workforce, contributing to sustainable growth and success

Enhancing heavy equipment engineering students' skills through hydraulic and pneumatic systems training at SMKN 1 Sungai Limau

In the era of globalization, proficient technical skills are essential, especially in the field of heavy equipment engineering which requires an understanding of hydraulic and pneumatic systems. SMKN 1 Sungai Limau faces the challenge of limited facilities in preparing students for the demands of this industry. This training program utilizes a Problem-Based Learning method for theory and Project-Based Learning for practical application. Before the training commenced, students underwent a pretest with an average score of 45, indicating a low initial understanding. Following the theoretical and hands-on practical sessions, the posttest results showed a significant improvement with an average score of 70, reflecting an increase in student comprehension and skills. This average increase of 25 points serves as concrete evidence that this training is effective in enhancing students' skills in hydraulic and pneumatic systems. However, improvements in facilities and collaboration with industry are needed to ensure the relevance and sustainability of this training.

The Research of Diesel Engine Assembly Consistency Influence NOx Emission Based on Uniform Design Method

ABSTRACT Diesel engines need to meet the higher emission requirement according to the Euro VI emission standards, and changes in the assembly tolerance of diesel engines will affect the consistency of nitrogen oxides(NOx) emissions. To study the influence of assembly tolerance on NOx emission, a heavy diesel engine was used as the research prototype. The combustion model of the diesel engine was simulated by the Converge software and calibrated with the bench test data. Because the combustion system parameters have a significant impact on emissions, a three-factor eleven-level uniform design is arranged with three parameters, including compression ratio, fuel injection nozzle extension height and injection advance angle. The regression analysis method is used to obtain the relationship between the parameters and NOx emissions. The R2 test value of the regression equation is 0.916 and the F test value is 43.5, which shows that the results of the analysis are very effective. Then the single factor test method is applied to analyze the varying laws of compression ratio, nozzle extension height and fuel injection advance angle on NOx emissions, and the results reveal the inherent law similar to the regression equation. According to the Euro VI emission standards and the law of diesel engine emission performance consistency, the tolerance variation range of the key dimensions of the assembly parameters is obtained.

ANALISIS PENGARUH OPERATING CASH FLOW, PROFITABILITAS, SALES GROWTH, FIRM SIZE, DAN LEVERAGE TERHADAP PREDIKSI KONDISI FINANCIAL DISTRESS

The phenomenon of PKPU (Application for Insolvency and Delayed Debt Payment) on some issuers in the IDX appears to indicate financial problems (financial distress). The research was conducted to test and analyze the impact of operating cash flow, profitability, sales growth, firm size, and leverage on the prediction of financial distress conditions in sub-sector companies heavy construction and civil engineering registered in the IDX in 2020-2022. The sampling techniques used are purposive samplings with samples obtained of 60 data. The quantitative method is used in this study through an associative approach using secondary data as well as using double linear analysis with the SPSS version 22 test tool. The results of this study show that the profitability variables with proxy return on asset have a significant impact on financial distress, while the operating cash flow, sales growth, firm size, and leverage variables of proxy debt to asset ratio have no influence on financial stress. The implications of this study are expected to inform investors to always do financial analysis first before making decisions in the heavy construction and civil engineering subsectors.

Low-cycle fatigue of welded joint from steel of X70 strength class

Steels of X70 strength class are particularly widely used in the field of heavy engineering. One of the most important issues when choosing steel for structures is its behavior under cyclic loads. It is difficult to find a description of the behavior of all zones of the welded joint under fatigue. The purpose of this study was to determine the fatigue characteristics of welded joints made of the Russian analogue of S690QL steel with fixation of acoustic and magnetic parameters for their use in the diagnosis. The objects of the study were the samples from domestic steel of X70 strength class. The chemical composition was determined using optical emission spectrometry. The grinds for microstructural analysis were prepared according to the standard technique with etching in the metal. The fatigue test was carried out on a specialized test bench. The authors used the acoustic system AIS NRK-3 for acoustic measurements and the acoustic parameter D – as an informative parameter. A MA-412MM coercitimeter was applied to evalua­te the magnetic characteristics. The following were evaluated: residual magnetization Br , coercive force Hc , Hc/Br ratio. The smallest number of cycles corresponds to the deposited metal zone. The decrease in amplitude showed a significant variation in the behavior of the material depending on the junction zone. However, the curves for heat affected zone (HAZ) and the deposited metal are practically the same. HAZ differs to a lesser extent from the base metal than the deposited metal zone. The graph of the acoustic parameter in its form is the reverse of the magnetic characteristics graph. Thus, there is a minimum for the acoustic parameter, depending on the operating time, and a maximum for the magnetic characteristics. For both graphs, the extremum is the point corresponding to the operating time of 0.6.

Supersonic Waves Generated by the 18 November 2023 Starship Flight and Explosions: Unexpected Northward Propagation and a Man‐Made Non‐chemical Depletion

AbstractOn 18 November 2023, SpaceX launched the Starship, the tallest and the most powerful rocket ever built. The Super Heavy engine separated from the Starship spacecraft and exploded at 90 km of altitude, while the main core Starship continued to rise up to 149 km and exploded after ∼8 min of flight. In this work, we used data from ground‐based GNSS receivers and we analyzed total electron content (TEC) response to the Starship flight and the two explosions. For the first time, we observed large‐distance northward propagation of intensive 2,000 km V‐shaped ionospheric disturbances from the rocket trajectory. The observed perturbations, most likely, represent shock waves propagating with the cone angle of ∼14° on the North and ∼7° on the South against the flight track that corresponds to the Mach angle of the shock waves in the lower atmosphere. The Starship explosion also produced a non‐chemical depletion in the ionospheric TEC.

Evaluation of the ducted fuel injection concept for medium duty engines and multi-hole nozzles: An optical analysis

Ducted Fuel Injection (DFI) is a strategy still in development, which has proved to be effective in reducing soot emissions in compression ignition engines. It works by driving the spray, formed by a high-pressure fuel injection, through a small duct co-axial to the spray itself, which is expected to affect the mixture formation and combustion process, in turn leading to noticeable reduction in soot formation. This strategy has been mostly deployed in spray vessels or in some cases in heavy duty engines consisting of mostly 2-to-4-hole nozzle injectors. For this reason, the work here is aimed to study the potential of DFI in a medium-duty single-cylinder optical engine fueled with conventional diesel having an 8-hole nozzle injector. Two different optical techniques including OH* chemiluminescence and 2-color pyrometry have been utilized to perform the analysis regarding combustion evolution and soot formation. A parametric analysis regarding different geometrical parameters including stand-off distance, diameter and length of duct has been carried out regarding the DFI performance. Results indicate that DFI does decrease the soot emissions in the context of this study and the duct geometrical parameters influence combustion evolution and soot formation ultimately affecting the device's performance. However, the scale of soot reduction is not as high as reported in previous studies, which is limited by specific boundary conditions including combustion chamber design, piston geometry utilized in this study.

Investigation on recycling and reprocessing ability of self-healing natural rubber based on ionic crosslink network

Abstract Natural rubber (NR) is a complex material that is often discarded due to its three-dimensional structure. Recycling of rubber is difficult due to its complex structure, and only 1.7 million tonnes of waste, such as tyres and gloves, are considered recyclable. This study aims to develop self-healing rubber, which allows a product to recover without affecting structural reliability. Commercial NR was ionically crosslinked with zinc thiolate, forming an ionic crosslink network between rubber chains and zinc thiolate ions. The ionic crosslinks allow the rearrangement of rubber molecular chains under external heat, providing self-healing capabilities. The highest ionic crosslink density was found in NR with 35 phr zinc thiolate. The self-healing NR can recover 90 % of its initial properties at room temperature for 10 min and can be reprocessed and recycled three times without compromising its properties. It also shows excellent weldability, making it a promising material for repairing existing rubber products in heavy engineering applications.

Petrography and geomechanical properties of some mine waste rocks from the Tarkwaian Group in Ghana: implications for their use as aggregates in general engineering works

This research investigated some mine waste rocks from the southwestern part of the Tarkwaian Group in Ghana to check their suitability for general engineering works using petrography and geomechanical characteristics of the rocks. The rocks were subjected to a total of ten (10) tests, including Aggregate impact value (AIV), Aggregate crushing value (ACV), Loss Angeles abrasion (LAA), Specific gravity (SG), and Water absorption (WA), as well as flakiness and elongation index, slake durability (SD), chloride test (CT), sulphate test (ST), and ten percent fines (TPF). The tests were carried out per the American Society for Testing and Materials guidelines (ASTM). The following average test results were obtained: AIV (7.12%), ACV (15.60%), LAA (23.16%), TPF (269.7 kN), sulphate (0.0215%), chloride (0.00123%), flakiness (39.5%) and elongation (39.4%). The mine waste rocks are dominated by quartz and sericite, according to the petrographic examination and thus, can be classified as quartzites. Except for the flakiness and elongation index tests, all the results were consistent with the ASTM standards. The analysis carried out on the selected mine waste rocks from the southwestern part of the Tarkwaian Group could be catastrophic for heavy engineering works such as roads, bridges, and heavy buildings but can be used for pavements, lightweight buildings, monuments, and decoratives due to the percentage of quartz present to compensate for the weakness posed by the sericite.

Bringing architecture-based adaption to the mainstream

Software architecture has been shown to provide an appropriate level of granularity for representation of a managed software system and reasoning about the impact of adaptation choices on its properties. Software architecture-based adaptability is the ability to adapt a software system in terms of its architectural elements, such as its components and their interfaces. Despite its promise, architecture-based adaptation has remained largely elusive, mainly because it involves heavy engineering effort of making non-trivial changes to the manner in which a software system is implemented. In this paper, we present Acadia—a framework that automatically enables architecture-based adaptation of practically any Java 9+ application without requiring any changes to the implementation of the application itself. Acadia builds on the Java Platform Module System (JPMS), which has brought extensive support for architecture-based development to Java 9 and subsequent versions. Acadia extends JPMS with the ability to provide and maintain a representation of an application’s architecture and make changes to it at runtime. The results of our experimental evaluation, conducted on three large open-source Java applications, indicate that Acadia is able to efficiently apply dynamic changes to the architecture of these applications without requiring any changes to their implementation.

Exploiting Lubricant Formulation to Reduce Particle Emissions from Gas Powered Engines

The present paper illustrates the results of an experimental study aimed at evaluating the effect of lubricant oil features on the emissive behaviour of a heavy duty spark ignition engine fuelled with methane. The activity was performed within a research project between CNR-STEMS and TotalEnergies in which oils with different formulations were characterized, focusing on their potentiality in particle emission reduction. Considering the ultralow particle emission level in the exhaust of gas engines, a specific testing procedure was designed to guarantee highly reliable and accurate results. In particular, the engine was operated under transient conditions, along the World Harmonized Transient Cycle in cold- and hot-start conditions. The results of the test campaign clearly highlight that the lubricant formulation is a key technology for the control of particles, revealing this as an important aspect in view of the upcoming severe regulation limits on particle emissions. The experimental findings show the capability of reformulated oils to drop down the total particle number to 60–70% with respect to a baseline standard oil. The interest in the present study also lies in providing information extendable to more sustainable fuels, like hydrogen or biomethane, nowadays of great interest as alternative energy sources.

Correlating wear with the lubricant properties of heavy-duty diesel engine oils

Wear volumes were correlated with the lubricant properties of 11 used, heavy duty engine oil samples. The most important oil property in predicting wear volume is Total Acid Number, TAN. Here, the TAN value may be indicating ZDDP in its oxidised form and unable to participate in corrosive-abrasive wear. Low wear also correlates with mean soot particle size/circularity, which further suggests the abrasive aspect of this mechanism. Finally, low wear correlates with high calcium concentration in the fresh oil. This suggests a new wear reduction mechanism in which calcium from the detergent replenishes the iron within the ZDDP antiwear film.

The Role of Value Stream in Measuring Environmental Costs and Reducing Costs

Most economic units suffer from high rates of environmental pollution and a shortage of available resources and energy. This iead to a significant increase in production costs. In addition the economic units lack of using modern cost methods through which environmental costs and production costs are identified, allocated and measured. One of these methods is the value flow method . which works to track production processes, analyze inputs and outputs, and classify them into sound products and unhealthy products (waste).This in turn enables management to identify value-added activities and non-value-added activities, and works to reduce environmental impacts, the amount of waste, and reduce losses that occur during production, Therfure the production process and optimal exploitation of resources, reduce product costs and producing environmentally friendly products, and this leads to improving environmental performance in Iraqi economic units. The research aims to restructure the economic unit, which is managed through its departments and manage it according to the value flow method and to calculate environmental costs. For the purpose of achieving the objectives of this study and testing the hypotheses, the General Company for Heavy Engineering Equipment waschosen.The sample is one of the companies of the Ministry of Oil . relying on the financial and non-financial data that it included. Reports and records for the year 2021-2022.as well as field consultation and deliberation of questions with engineers, specialists and workers to benefit from their accumulated experience.The collected data are anaiysed according to value flow cost accounting in order to improve the production process, and in order to reduce environmental impacts, the amount of waste and emissions, and optimal exploitation of resources and energy. The most important conclusions reached by the researcher were the ability of the value flow to calculate the environmental costs of each flow within the economic unit, as well as providing more accurate and objective data and information for making decisions and measuring the performance of the economic unit to contribute to monitoring environmental activities and the possibility of reducing the costs of those activities.

Pengaruh Struktur Modal dan Pertumbuhan Perusahaan terhadap Nilai Perusahaan dengan Profitabilitas sebagai Variabel Intervening (Studi Pada Perusahaan Infrastruktur Sub Sektor Konstruksi Berat dan Teknik Sipil Terdaftar di BEI Periode 2018-2022

This research aims to analyze the influences: (1) capital structure influences the value of the company, (2) corporate growth influences corporate value, (3) capital structures influence profitability, (4) corporate development influences profits, (5) profitability influences company value, (6) profitability is able to mediate the influence of capital structure on the company's value, (7) profitability can mediate company growth influence on company value. The population of this study is the entire infrastructure company of the heavy construction and civil engineering sub-sector listed on the Indonesian Stock Exchange for the period 2018-2022. The samples were selected using the purposive sampling method of 18 companies. Data analysis used in this study is internal model and hypothesis testing with the help of software SmartPLS (Partial Least Squares) version 3.2.9. PLS (Partial Least Square). The results of the research showed that the capital structure had a negative and non-significant impact on the company's value, the growth of the company had a positive and insignificant effect on the value of the enterprise, the structure of the capital had an negative and significant impact on profitability, the development of a enterprise had an positive and significant effect on profitability, the profitability had an adverse and significant influence on the corporate value, profitability was able to mediate the influence of capital structures on the business' value, and profitability were capable of mediating the impact of the growth and value of an enterprise.