Alireza Esfandyari

Application of value stream mapping using simulation to decrease production lead time: a Malaysian manufacturing case

Lean concept has been applied across many companies which offer value and eliminate wastes. Value stream map (VSM) as one of the fundamental tools in lean concept outlines the material and information flows for a product family to reduce wastes at discrete event production routine. In this paper, the improvement of the production lead time using VSM as a technique in a Malaysian supplier, with a job shop production system, is investigated. The main contribution of this paper is reducing production lead time when the Takt Time is much higher than the highest stations cycle time, and reducing unplanned released orders. This paper evaluates the present routing events using current state map and the future state is created answering the eight standard questions. Then, a detailed simulation model was developed to verify the result from future state map and answering the questions that are unable to be addressed by VSM.

Energy Efficiency Investigation on High-Pressure Convection Reflow Soldering in Electronics Production

One of the key factors in efficient and defect-free electronics manufacturing is the soldering of electronic components to the printed circuit boards. The deciding factor in the reliability and lifetime of the product is the quality of the soldered interconnections. The setting up of the reflow soldering profile plays a crucial role in the electrical functionality and robustness of the product. Especially the miniaturization of the assemblies and the development of new materials make it inevitable for the definition of new processes, optimization and implementation. In this paper, the combination of over-pressure and convection reflow soldering to minimize the defect rate and the related energy analysis for energy efficiency will be discussed and presented. A statistical analysis with variations in solder time, cost, energy, quality trade-off in the over-pressure reflow soldering process for classical printed circuit boards (PCBs) has been demonstrated.

Energy Efficiency Analysis of Vapor Phase Soldering Technology through Exergy-Based Metric

In electronics production, the condensation based soldering technologies are known for reproducible solder profiles and efficient heat transfer methodology. The recent advancements in lead-free soldering and requirements for absolute void-free interconnections to increase the reliability and lifetime of the product needs optimization of the soldering process. The vacuum assisted vapor phase soldering process addresses the requirements with respect to mass production and parallelly resource efficient production which is also the motivation for the present work. This study is devoted to quantify the resource consumption and qualify this consumption through exergy flows in a vacuum vapor phase reflow soldering technology in electronics manufacturing.The analysis implies on the saving potential for energy consumption specifically during the vacuum process which also defines the void reduction quality of solder joints. Exergy efficiency analysis of a temperature profile depicts the influence of the materials used in the demonstrator. Shortening the production lead‑time, and increasing the production rate increase the efficiency of exergy and prevents wastage of usable energy. Furthermore, the set-up improvements for the temperature profiles processes are necessary, and the changes toward developing new, transformational technologies in pre-heating and vacuum zones are mandatory if a high efficiency of resources used is aimed.

An Exergy-Based Analysis of Temperature Profiles for an Over-Pressure Reflow Oven Technology

In electronics assembly, the convection based soldering technologies in the production lines consumes massive resources and energy. The recent advancements in soldering technologies consume comparatively higher resources and needs to be optimized for resource efficient production which is also the motivation for the present work. This study is devoted to quantify the resource consumption and qualify this consumption through exergy flows in an over-pressure reflow technology as an energy intensive process in electronics manufacturing.The analysis implies on a big saving potential for energy consumption specifically during the over-pressure process which also defines the void reduction quality of solder joints. Exergy efficiency is the fraction of the work potential of the heat that is converted to work, and it illustrates the quality of consumed resources during the soldering oven process. Shortening the production lead-time, and increasing the production rate increase the efficiency of exergy and prevents wastage of usable energy. Furthermore, the set-up improvements for the temperature profiles are necessary, and the changes toward developing new technologies in pre-heating and over-pressure chamber zones are mandatory if a high efficiency of resources used is expected.Copyright

A Lean-Based Key Performance Analysis for a Resource Efficient Soldering Oven in Electronics Production

The reflow soldering in electronics production is identified as an energy-intensive process that requires further resource efficiency optimization. A lean-based analysis of the resource consumption in production at different factory levels illustrates the minimum resource consumption and saving potentials in the soldering process. The four levels namely factory, machine, process, and product represent the hierarchical structure within the production facility and establish a transparent overview model. The value-added energy investigation is conducted at all levels, and additionally the exergy method is used in the product level to investigate the material transformation efficiency and the minimum resource consumption in the model. The results in different levels illustrate the energy efficiency of each level, the energy wastage, and the potential for further optimization.

Energy Efficient Manufacturing of Power Electronics Substrates through Selective Laser Melting Technology

In view of rising energy prices, high-energy consumption, and the associated environmental problems, in recent years the focus was shifted on the demand for energy and resource efficiency in the manufacturing sector. In the context of the project ‘PowerSLAM’ under Green Factory Bavaria Project, the feasibility of selective laser melting technology (SLM) for the production of ceramic circuit carriers is investigated. In this paper, an overview on the comparison of the state-of-the-art technologies with SLM technology is given in the perspective of energy and resource consumption. Parallelly the results of the investigations of SLM technology i.e. process feasibility and optimization for melting of copper based powders on ceramic substrates is summarized. The process parameters such as laser power, laser scan velocity and scan strategies are investigated. Based on the energy measurements, the process parameters are optimized accordingly for efficient process and overview on the resource and energy consumption is given. Demonstrators are built based on confined parameter combinations showing the process compatibility and the efficiencies are calculated accordingly. Here the approach bottom-up is considered to do the comprehensive process comparison and the energy efficiency value is considered in accessing the process and related energy efficiency.

Identification of Energy Consumption and Energy Saving Potentials of Electric Drive Systems

This paper provides an overview of different types of motor systems and several measurement principals in order to determine the electricity usage of these motors. It focuses on the measurement of electric values of different drive systems. A concept of rough analysis using software or excel based tools is discussed, which shows that it is a lot easier, efficient, and cost effective to first pin point the main electricity consumers and then initiate a fine analysis of these selected systems before a cost and time intensive process of measuring every single drive system is undertaken. To achieve this, a simple and systematic process is described in this paper, which can be used to identify the energy saving potential of drive systems without requiring expensive hardware.