Bucket is key and primary component of heavy construction machinery such as excavators. It has to bear high impact loads during digging process, resulting in large stress and deformations. This research work has been focused on reducing stress and deformations produced in excavator bucket due to digging. For this purpose, different design patents of excavator buckets (including ornamental designs) were considered. Various models of excavator buckets were developed by varying geometrical parameters such as number of blade teeth/tips and bucket curvature. Finite element analysis of these models was carried out by using ANSYS in order to determine stress and strains. Maximum values of Von Mises stress, principal stress, factor of safety and total deformation were evaluated numerically for all three-dimensional geometric models. Excavator bucket with least values of stress and deformations, but largest factor of safety, was identified through numerical computations. Mechanical performance of ornamental buckets having quarter circular curvature with 6 blade teeth was observed to be better as compared to designs having single blade strip or 5 blade teeth. Mass reduction up to 2.5%, while the stress reduction and factor of safety enhancement up to 9.6% was achieved by incorporating 6 blade teeth in ornamental design of excavator bucket.

The successfulness of Value Stream Mapping (VSM) as a tool for taking a snapshot of the production flow efficiency is well established. The development of a large-scale visual map of processes and their interactions is beneficial for problem analysis and subsequent solution. Through VSM, managers gain a deeper understanding of the organization processes carried out in coordination with people in a system approach. A case study was conducted at a Small and Medium Enterprise (SME) in Pakistan which manufactures ceiling fan winding machines. The aim of this study was to explore the possibilities of shortening the lead-time, waste and highlight important strategies, steps which could be undertaken by management for improvement in productivity, cost and quality. The study maps the organization systematically through the use of VSM. The Lean Implementation Techniques (LIT) steps were followed with identification of value stream process, lean metrics, mapping of current state and proposing an improved future state value stream map. The intervention suggested is layout modification by reducing 7 stations to 6 stations and streamlining the operations. The layout modification results in lower defects, controlling overproduction, managing inventory buffers from a linear approach to an optimized level. This also resulted in reduction of processing time of each unit by around 19 % and the production lead time of 100 units by around 21%. This study through VSM proposes improvement by enforcing pull system, supplier relations, modifying layout and production processes, Just in Time (JIT) delivery of materials and parts, scheduling transport resources efficiently and reducing inventory buffers.

Work Stress is a barrier towards productivity and efficiency in manufacturing sector. Various factors of stress interact with the demographics such as age, education, experience, marital status and smoking habits of workers. Different workers exhibit different reactions towards work stress. To enhance productivity, manufacturing industry is utilizing night shift. However, night shift work is against the natural tendency of humans. The impact of rotating shift in context of work-stress of the workers is an area of concern. To understand the impact of demographics and shift rotation on work-stress of the workers, a quantitative study was undertaken in a medium sized automotive organization. The case organization was explored through a survey questionnaire administered to both day and night shift workers and analysed through Non parametric Spearman correlation and Mann Whitney U Test. The study highlights the need for effective reward and gratification scheme (Young Worker Avg 3.12 – Old Worker Avg 3.82), taking care of old age workers (Muscle Pain Old Avg 4.47 – Young Avg 3.84), reducing the smoking habit (Depression Smoking Avg 3.79 – Non Smoking Avg 3.12) (Fatigue Smoking Avg 3.92 – Non Smoking Avg 3.06), fostering social community and teamwork. Night shift may enhance production but should not be accepted as an ideal solution. The downsides and ill effects of the unnatural night shift work in the form of work stress are identified and should be reduced by management.

Aerodynamic drag of fast-moving train has significant impact on its fuel consumption and design safety. To improve aerodynamic performance, the drag forces on the train surfaces must be reduced. Train’s front-end nose design has boundless geometrical variations that can be applied for improved performance. Three geometric characteristics were used in present research: A-pillar roundness, nose length that controls its shrinking, and nose bluntness. Latin-Hypercube based random sampling method was used to determine appropriate values of these parameters for specific range. Using Computational Fluid Dynamics (CFD), a numerical approach was used to analyze train aerodynamic performance based on selected factors and operating conditions. Comparisons based on analysis of the base design and proposed design models were made and evaluated for enhanced performance. CFD analysis of the base design and iterative improvements in modified designs indicate drag reduction through change in A-pillar roundness and bluntness of nose to be 10% and 22%, respectively. The increase in nose length which controls nose shrinkage causes the drag to increase by 35%. Similarly, the boundary layer and pressure distribution on the front end of train were also considered and analyzed for performance improvement. It was concluded that the length controlling nose shrinkage of proposed train design is the key factor among the selected geometric parameters that has more influence on drag on high-speed train surface in comparison to other parameters considered. This research effort offers a modification, analysis and comparison of front-end nose geometry of high-speed train to improve aerodynamic performance and consequently fuel consumption.

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