Tarun Gupta

Production data based similarity coefficient for machine-component grouping decisions in the design of a cellular manufacturing system

SUMMARY This paper presents a similarity coefficient based approach to the problem of machine-component grouping. The proposed method incorporates relevant production data such as part type production volume, routing sequence and unit operation time in the early stages of grouping decisions for cellular manufacturing. The algorithm also suggests a methodology for evaluating alternative solutions from different algorithms on a quantitative basis using a modified version of an existing coefficient. The modified quantitative measure is a comprehensive indicator for the goodness of a grouping solution. The algorithm then identifies bottleneck machines and corresponding cell candidates for their duplication using percentage utilization in each cell as a criterion. Finally, additional constraints can be applied to determine the best grouping solution among alternative solutions generated by the algorithm. A software package has been developed to verify the implementation.

An empirical study of just‐in‐time and total quality management principles implementation in manufacturing firms in the USA

Analyses, through a nationwide empirical survey of US companies, the effects of JIT and TQM strategies and offers important guidelines for JIT/TQM programme co‐ordinators that might be helpful during the implementation process. Shows that while companies can benefit from implementation of JIT alone in some areas of manufacturing practices, a good TQM system must be in place both at the company’s and at the supplier’s end. Also shows that the implementation of both JIT and TQM strategies contributes most to increased productivity, employee involvement, management commitment, supplier participation, enhancement in quality and reduction in costs. Even firms that implement one of the two strategies, JIT or TQM, reflect increased productivity and improved quality when compared with the firms that implement none. Finally, indicates that firms which implement both strategies have 40 per cent more quality certifications than the rest.

JIT and TQM: A case for joint implementation

The post‐Second World War era has seen the emergence of two strategies to improve the operational effectiveness of manufacturing firms: just‐in‐time (JIT) production systems and total quality management (TQM). Both evolved in Japan, and the West deciphered and applied them later. TQM has evolved in Japan over the last four decades, and JIT principles were developed and applied as an integral part of TQM philosophy. The West, however, deciphered JIT elements of Japanese manufacturing excellence first, followed by recognition of TQM as the underlying philosophy. Hence, these are viewed by a majority of Western researchers and practitioners in isolation (the traditional view). Examines the linkages between JIT and TQM from conceptual, philosophical, and implementation perspectives. Theorizes a synergistic interaction between JIT and TQM when they are viewed as an integrated strategy where JIT is an integral part of TQM philosophy (the integrated view). Provides theoretical support for the thesis that the org...

Design of manufacturing cells for flexible environment considering alternative routeing

In flexible manufacturing system (FMS), it is common that most machines are multi-purpose and are capable of performing more than one operation, which makes parts rerouteing possible. In addition, due to scheduling constraints, rerouteing is often desirable. Also, interruptions in production activity due to machines failure from time to time is a common problem, and that too requires parts rerouteing to meet the due-date requirements. Historically, machine grouping procedures do not consider alternative routeings that a part may undergo during the operational phase of the system. When a part is rerouted, it adversely affects the cell performance. The existing procedures for machine cells formation in cellular manufacturing have not taken these factors into consideration. In this research, a new heuristic procedure is developed which provides the flexibility of incorporating alternative routeings in the systems design phase itself. To illustrate the validity of this heuristic, a case example problem is de...

Looping in a multistage production system

Abstract Multistage production systems have been an important quest of researchers over many years. While much work has been reported in this area little appears to have been done when recycling, an inevitable factor in any production system, is present. In this paper, a model for optimal production batch quantity as well as optimal recycling lot size has been developed with a view to minimizing the total operational cost of such situations, where recycling takes place only from the last stage to the first. The model has been validated using sample data from a glassworks, located in Western India. The effects of changes of model parameters were also studied and practical guidelines arising out of the same have been provided.

An expert system approach in process planning current development and its future

Abstract This paper discusses the findings of a survey conducted for the state of the art for expert-system-based automated process planning systems. The need for an expert system approach in the process planning function is emphasized. Subsequently, the important features and limitations of the various reported systems are presented, with respect to their part design input scheme, knowledge base representation, and the control strategy. Finally, recommendations are made for possible future directions in the research of a more efficient computer-aided process planning (CAPP) module.

Production capacity analysis of a shock absorber assembly line using simulation

This paper reports findings of a study of shock absorber assembly line using computer simulation. The shock absorber assembly line feeds shockers to the motorcycle assembly line. The assembly line simulated in this project is located at an OEM for Bajaj Auto Ltd., the largest producers of scooters and motorcycles in India. In this paper, results of simulation are presented from two scenarios. The first is the original layout of the system. The second simulation is the suggested modifications. Data was gathered and evaluated to determine the necessary parameters to be used. The new demand required the OEM to increase its capacity by 200 shock absorbers per day. After implementing the proposed model the daily output increased by 435 shock absorbers. The highlights of our analysis was that this increase in production rate was achieved without any increase in direct labor, contributing to a gross increase in profit by 32%.

Analysing Materials Handling Needs in Concurrent/Simultaneous Engineering

In simultaneous/concurrent engineering (SE/CE), many functions are performed concurrently; however, manufacturing logistics design is seldom considered. Presents an integrated methodology for the design of manufacturing logistics and links it with early phases of product design. The concept of “adaptability factor” is proposed, linking choice of manufacturing technology to handling operations performed.

Determination of optimal lot sizing parameters and a controllable process mean for a production system

Several mathematical models have been developed separately for determining production and recycled lot quantities to minimize total production cost and the determination of optimal process mean setting to minimize total quality cost. For a single stage discrete part production system, this paper presents a mathematical model that combines these two inter-related aspects. The production process has a controllable parameter, the process mean, which determines the output lot quality. One-sided tolerance is used to decide the quality of finished goods. Bad units are reworked before they can be reprocessed with the fresh input. For such a situation, the model determines production lot size, recycling lot quantity, and a process mean while minimizing total system cost. The model has been validated using sample data from a pharmaceutical company. Results indicate that the production lot size and the recycled quantity have an inverse relationship with process mean and, a direct relationship with process variance.

Design and implementation scheme for an alternate process planning system—A-CAPPS

Abstract This paper presents the design and development of a computer-aided process planning system (CAPP) that generates least-cost alternate plans. The developed system takes production capacity, machine capability, and operation cost into account to determine feasible process plans for a product mix. Traditional CAPP systems generate one process plan per part. Their use in most production systems has been found to be limited due to frequent non-availability of machines and other resources recommended by the CAPP system. In addition, advanced manufacturing systems such as an FMS normally offer alternate feasible routes for part production. Hence, CAPP systems should be able to generate cost-efficient alternate process plans that can be adopted to circumvent such problems. The proposed methodology integrates order processing, aggregate planning, resource grouping, loading, process cost estimation, process planning, and finally scheduling. It considers loading of part families to each cell in the FMS. Each cell is generally known as a flexible manufacturing cell (FMC). The total workload of a part is divided into batches, based on the demand for a planning period. Different batches of a part mix required in the planning period will determine the part production schedule (PPS). The development of a prototype system based on a variant approach is discussed. The system a-capps is capable of generating alternate process plans to satisfy various capacity constraints. The plan combination for a product mix generated by a-capps is then evaluated for system performance using a simulation model. A case example is discussed to demonstrate the applicability of the developed system.